diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2025-12-05 17:01:20 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-12-05 17:01:20 -0800 |
| commit | 51d90a15fedf8366cb96ef68d0ea2d0bf15417d2 (patch) | |
| tree | f211728418ec63471fcc0c37058326e678808ac0 /arch/x86/kvm | |
| parent | 399ead3a6d76cbdd29a716660db5c84a314dab70 (diff) | |
| parent | e0c26d47def7382d7dbd9cad58bc653aed75737a (diff) | |
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"ARM:
- Support for userspace handling of synchronous external aborts
(SEAs), allowing the VMM to potentially handle the abort in a
non-fatal manner
- Large rework of the VGIC's list register handling with the goal of
supporting more active/pending IRQs than available list registers
in hardware. In addition, the VGIC now supports EOImode==1 style
deactivations for IRQs which may occur on a separate vCPU than the
one that acked the IRQ
- Support for FEAT_XNX (user / privileged execute permissions) and
FEAT_HAF (hardware update to the Access Flag) in the software page
table walkers and shadow MMU
- Allow page table destruction to reschedule, fixing long
need_resched latencies observed when destroying a large VM
- Minor fixes to KVM and selftests
Loongarch:
- Get VM PMU capability from HW GCFG register
- Add AVEC basic support
- Use 64-bit register definition for EIOINTC
- Add KVM timer test cases for tools/selftests
RISC/V:
- SBI message passing (MPXY) support for KVM guest
- Give a new, more specific error subcode for the case when in-kernel
AIA virtualization fails to allocate IMSIC VS-file
- Support KVM_DIRTY_LOG_INITIALLY_SET, enabling dirty log gradually
in small chunks
- Fix guest page fault within HLV* instructions
- Flush VS-stage TLB after VCPU migration for Andes cores
s390:
- Always allocate ESCA (Extended System Control Area), instead of
starting with the basic SCA and converting to ESCA with the
addition of the 65th vCPU. The price is increased number of exits
(and worse performance) on z10 and earlier processor; ESCA was
introduced by z114/z196 in 2010
- VIRT_XFER_TO_GUEST_WORK support
- Operation exception forwarding support
- Cleanups
x86:
- Skip the costly "zap all SPTEs" on an MMIO generation wrap if MMIO
SPTE caching is disabled, as there can't be any relevant SPTEs to
zap
- Relocate a misplaced export
- Fix an async #PF bug where KVM would clear the completion queue
when the guest transitioned in and out of paging mode, e.g. when
handling an SMI and then returning to paged mode via RSM
- Leave KVM's user-return notifier registered even when disabling
virtualization, as long as kvm.ko is loaded. On reboot/shutdown,
keeping the notifier registered is ok; the kernel does not use the
MSRs and the callback will run cleanly and restore host MSRs if the
CPU manages to return to userspace before the system goes down
- Use the checked version of {get,put}_user()
- Fix a long-lurking bug where KVM's lack of catch-up logic for
periodic APIC timers can result in a hard lockup in the host
- Revert the periodic kvmclock sync logic now that KVM doesn't use a
clocksource that's subject to NTP corrections
- Clean up KVM's handling of MMIO Stale Data and L1TF, and bury the
latter behind CONFIG_CPU_MITIGATIONS
- Context switch XCR0, XSS, and PKRU outside of the entry/exit fast
path; the only reason they were handled in the fast path was to
paper of a bug in the core #MC code, and that has long since been
fixed
- Add emulator support for AVX MOV instructions, to play nice with
emulated devices whose guest drivers like to access PCI BARs with
large multi-byte instructions
x86 (AMD):
- Fix a few missing "VMCB dirty" bugs
- Fix the worst of KVM's lack of EFER.LMSLE emulation
- Add AVIC support for addressing 4k vCPUs in x2AVIC mode
- Fix incorrect handling of selective CR0 writes when checking
intercepts during emulation of L2 instructions
- Fix a currently-benign bug where KVM would clobber SPEC_CTRL[63:32]
on VMRUN and #VMEXIT
- Fix a bug where KVM corrupt the guest code stream when re-injecting
a soft interrupt if the guest patched the underlying code after the
VM-Exit, e.g. when Linux patches code with a temporary INT3
- Add KVM_X86_SNP_POLICY_BITS to advertise supported SNP policy bits
to userspace, and extend KVM "support" to all policy bits that
don't require any actual support from KVM
x86 (Intel):
- Use the root role from kvm_mmu_page to construct EPTPs instead of
the current vCPU state, partly as worthwhile cleanup, but mostly to
pave the way for tracking per-root TLB flushes, and elide EPT
flushes on pCPU migration if the root is clean from a previous
flush
- Add a few missing nested consistency checks
- Rip out support for doing "early" consistency checks via hardware
as the functionality hasn't been used in years and is no longer
useful in general; replace it with an off-by-default module param
to WARN if hardware fails a check that KVM does not perform
- Fix a currently-benign bug where KVM would drop the guest's
SPEC_CTRL[63:32] on VM-Enter
- Misc cleanups
- Overhaul the TDX code to address systemic races where KVM (acting
on behalf of userspace) could inadvertantly trigger lock contention
in the TDX-Module; KVM was either working around these in weird,
ugly ways, or was simply oblivious to them (though even Yan's
devilish selftests could only break individual VMs, not the host
kernel)
- Fix a bug where KVM could corrupt a vCPU's cpu_list when freeing a
TDX vCPU, if creating said vCPU failed partway through
- Fix a few sparse warnings (bad annotation, 0 != NULL)
- Use struct_size() to simplify copying TDX capabilities to userspace
- Fix a bug where TDX would effectively corrupt user-return MSR
values if the TDX Module rejects VP.ENTER and thus doesn't clobber
host MSRs as expected
Selftests:
- Fix a math goof in mmu_stress_test when running on a single-CPU
system/VM
- Forcefully override ARCH from x86_64 to x86 to play nice with
specifying ARCH=x86_64 on the command line
- Extend a bunch of nested VMX to validate nested SVM as well
- Add support for LA57 in the core VM_MODE_xxx macro, and add a test
to verify KVM can save/restore nested VMX state when L1 is using
5-level paging, but L2 is not
- Clean up the guest paging code in anticipation of sharing the core
logic for nested EPT and nested NPT
guest_memfd:
- Add NUMA mempolicy support for guest_memfd, and clean up a variety
of rough edges in guest_memfd along the way
- Define a CLASS to automatically handle get+put when grabbing a
guest_memfd from a memslot to make it harder to leak references
- Enhance KVM selftests to make it easer to develop and debug
selftests like those added for guest_memfd NUMA support, e.g. where
test and/or KVM bugs often result in hard-to-debug SIGBUS errors
- Misc cleanups
Generic:
- Use the recently-added WQ_PERCPU when creating the per-CPU
workqueue for irqfd cleanup
- Fix a goof in the dirty ring documentation
- Fix choice of target for directed yield across different calls to
kvm_vcpu_on_spin(); the function was always starting from the first
vCPU instead of continuing the round-robin search"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (260 commits)
KVM: arm64: at: Update AF on software walk only if VM has FEAT_HAFDBS
KVM: arm64: at: Use correct HA bit in TCR_EL2 when regime is EL2
KVM: arm64: Document KVM_PGTABLE_PROT_{UX,PX}
KVM: arm64: Fix spelling mistake "Unexpeced" -> "Unexpected"
KVM: arm64: Add break to default case in kvm_pgtable_stage2_pte_prot()
KVM: arm64: Add endian casting to kvm_swap_s[12]_desc()
KVM: arm64: Fix compilation when CONFIG_ARM64_USE_LSE_ATOMICS=n
KVM: arm64: selftests: Add test for AT emulation
KVM: arm64: nv: Expose hardware access flag management to NV guests
KVM: arm64: nv: Implement HW access flag management in stage-2 SW PTW
KVM: arm64: Implement HW access flag management in stage-1 SW PTW
KVM: arm64: Propagate PTW errors up to AT emulation
KVM: arm64: Add helper for swapping guest descriptor
KVM: arm64: nv: Use pgtable definitions in stage-2 walk
KVM: arm64: Handle endianness in read helper for emulated PTW
KVM: arm64: nv: Stop passing vCPU through void ptr in S2 PTW
KVM: arm64: Call helper for reading descriptors directly
KVM: arm64: nv: Advertise support for FEAT_XNX
KVM: arm64: Teach ptdump about FEAT_XNX permissions
KVM: s390: Use generic VIRT_XFER_TO_GUEST_WORK functions
...
Diffstat (limited to 'arch/x86/kvm')
30 files changed, 1489 insertions, 1126 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 52524e0ca97f..d563a948318b 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -1135,6 +1135,7 @@ void kvm_set_cpu_caps(void) F(AMD_STIBP), F(AMD_STIBP_ALWAYS_ON), F(AMD_IBRS_SAME_MODE), + PASSTHROUGH_F(EFER_LMSLE_MBZ), F(AMD_PSFD), F(AMD_IBPB_RET), ); diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 4e3da5b497b8..c8e292e9a24d 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -81,9 +81,8 @@ */ /* Operand sizes: 8-bit operands or specified/overridden size. */ -#define ByteOp (1<<0) /* 8-bit operands. */ -/* Destination operand type. */ -#define DstShift 1 +#define ByteOp (1<<0) /* 8-bit operands. */ +#define DstShift 1 /* Destination operand type at bits 1-5 */ #define ImplicitOps (OpImplicit << DstShift) #define DstReg (OpReg << DstShift) #define DstMem (OpMem << DstShift) @@ -95,8 +94,7 @@ #define DstDX (OpDX << DstShift) #define DstAccLo (OpAccLo << DstShift) #define DstMask (OpMask << DstShift) -/* Source operand type. */ -#define SrcShift 6 +#define SrcShift 6 /* Source operand type at bits 6-10 */ #define SrcNone (OpNone << SrcShift) #define SrcReg (OpReg << SrcShift) #define SrcMem (OpMem << SrcShift) @@ -119,10 +117,10 @@ #define SrcAccHi (OpAccHi << SrcShift) #define SrcMask (OpMask << SrcShift) #define BitOp (1<<11) -#define MemAbs (1<<12) /* Memory operand is absolute displacement */ +#define MemAbs (1<<12) /* Memory operand is absolute displacement */ #define String (1<<13) /* String instruction (rep capable) */ #define Stack (1<<14) /* Stack instruction (push/pop) */ -#define GroupMask (7<<15) /* Opcode uses one of the group mechanisms */ +#define GroupMask (7<<15) /* Group mechanisms, at bits 15-17 */ #define Group (1<<15) /* Bits 3:5 of modrm byte extend opcode */ #define GroupDual (2<<15) /* Alternate decoding of mod == 3 */ #define Prefix (3<<15) /* Instruction varies with 66/f2/f3 prefix */ @@ -131,11 +129,8 @@ #define InstrDual (6<<15) /* Alternate instruction decoding of mod == 3 */ #define ModeDual (7<<15) /* Different instruction for 32/64 bit */ #define Sse (1<<18) /* SSE Vector instruction */ -/* Generic ModRM decode. */ -#define ModRM (1<<19) -/* Destination is only written; never read. */ -#define Mov (1<<20) -/* Misc flags */ +#define ModRM (1<<19) /* Generic ModRM decode. */ +#define Mov (1<<20) /* Destination is only written; never read. */ #define Prot (1<<21) /* instruction generates #UD if not in prot-mode */ #define EmulateOnUD (1<<22) /* Emulate if unsupported by the host */ #define NoAccess (1<<23) /* Don't access memory (lea/invlpg/verr etc) */ @@ -143,11 +138,11 @@ #define Undefined (1<<25) /* No Such Instruction */ #define Lock (1<<26) /* lock prefix is allowed for the instruction */ #define Priv (1<<27) /* instruction generates #GP if current CPL != 0 */ -#define No64 (1<<28) +#define No64 (1<<28) /* Instruction generates #UD in 64-bit mode */ #define PageTable (1 << 29) /* instruction used to write page table */ #define NotImpl (1 << 30) /* instruction is not implemented */ -/* Source 2 operand type */ -#define Src2Shift (31) +#define Avx ((u64)1 << 31) /* Instruction uses VEX prefix */ +#define Src2Shift (32) /* Source 2 operand type at bits 32-36 */ #define Src2None (OpNone << Src2Shift) #define Src2Mem (OpMem << Src2Shift) #define Src2CL (OpCL << Src2Shift) @@ -161,12 +156,13 @@ #define Src2FS (OpFS << Src2Shift) #define Src2GS (OpGS << Src2Shift) #define Src2Mask (OpMask << Src2Shift) +/* free: 37-39 */ #define Mmx ((u64)1 << 40) /* MMX Vector instruction */ -#define AlignMask ((u64)7 << 41) +#define AlignMask ((u64)3 << 41) /* Memory alignment requirement at bits 41-42 */ #define Aligned ((u64)1 << 41) /* Explicitly aligned (e.g. MOVDQA) */ #define Unaligned ((u64)2 << 41) /* Explicitly unaligned (e.g. MOVDQU) */ -#define Avx ((u64)3 << 41) /* Advanced Vector Extensions */ -#define Aligned16 ((u64)4 << 41) /* Aligned to 16 byte boundary (e.g. FXSAVE) */ +#define Aligned16 ((u64)3 << 41) /* Aligned to 16 byte boundary (e.g. FXSAVE) */ +/* free: 43-44 */ #define NoWrite ((u64)1 << 45) /* No writeback */ #define SrcWrite ((u64)1 << 46) /* Write back src operand */ #define NoMod ((u64)1 << 47) /* Mod field is ignored */ @@ -243,6 +239,13 @@ enum x86_transfer_type { X86_TRANSFER_TASK_SWITCH, }; +enum rex_bits { + REX_B = 1, + REX_X = 2, + REX_R = 4, + REX_W = 8, +}; + static void writeback_registers(struct x86_emulate_ctxt *ctxt) { unsigned long dirty = ctxt->regs_dirty; @@ -622,7 +625,6 @@ static unsigned insn_alignment(struct x86_emulate_ctxt *ctxt, unsigned size) switch (alignment) { case Unaligned: - case Avx: return 1; case Aligned16: return 16; @@ -924,7 +926,7 @@ static void *decode_register(struct x86_emulate_ctxt *ctxt, u8 modrm_reg, int byteop) { void *p; - int highbyte_regs = (ctxt->rex_prefix == 0) && byteop; + int highbyte_regs = (ctxt->rex_prefix == REX_NONE) && byteop; if (highbyte_regs && modrm_reg >= 4 && modrm_reg < 8) p = (unsigned char *)reg_rmw(ctxt, modrm_reg & 3) + 1; @@ -1030,6 +1032,7 @@ static void fetch_register_operand(struct operand *op) op->val = *(u64 *)op->addr.reg; break; } + op->orig_val = op->val; } static int em_fninit(struct x86_emulate_ctxt *ctxt) @@ -1075,17 +1078,17 @@ static int em_fnstsw(struct x86_emulate_ctxt *ctxt) return X86EMUL_CONTINUE; } -static void decode_register_operand(struct x86_emulate_ctxt *ctxt, - struct operand *op) +static void __decode_register_operand(struct x86_emulate_ctxt *ctxt, + struct operand *op, int reg) { - unsigned int reg; - - if (ctxt->d & ModRM) - reg = ctxt->modrm_reg; - else - reg = (ctxt->b & 7) | ((ctxt->rex_prefix & 1) << 3); - - if (ctxt->d & Sse) { + if ((ctxt->d & Avx) && ctxt->op_bytes == 32) { + op->type = OP_YMM; + op->bytes = 32; + op->addr.xmm = reg; + kvm_read_avx_reg(reg, &op->vec_val2); + return; + } + if (ctxt->d & (Avx|Sse)) { op->type = OP_XMM; op->bytes = 16; op->addr.xmm = reg; @@ -1103,9 +1106,20 @@ static void decode_register_operand(struct x86_emulate_ctxt *ctxt, op->type = OP_REG; op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; op->addr.reg = decode_register(ctxt, reg, ctxt->d & ByteOp); - fetch_register_operand(op); - op->orig_val = op->val; +} + +static void decode_register_operand(struct x86_emulate_ctxt *ctxt, + struct operand *op) +{ + unsigned int reg; + + if (ctxt->d & ModRM) + reg = ctxt->modrm_reg; + else + reg = (ctxt->b & 7) | (ctxt->rex_bits & REX_B ? 8 : 0); + + __decode_register_operand(ctxt, op, reg); } static void adjust_modrm_seg(struct x86_emulate_ctxt *ctxt, int base_reg) @@ -1122,9 +1136,9 @@ static int decode_modrm(struct x86_emulate_ctxt *ctxt, int rc = X86EMUL_CONTINUE; ulong modrm_ea = 0; - ctxt->modrm_reg = ((ctxt->rex_prefix << 1) & 8); /* REX.R */ - index_reg = (ctxt->rex_prefix << 2) & 8; /* REX.X */ - base_reg = (ctxt->rex_prefix << 3) & 8; /* REX.B */ + ctxt->modrm_reg = (ctxt->rex_bits & REX_R ? 8 : 0); + index_reg = (ctxt->rex_bits & REX_X ? 8 : 0); + base_reg = (ctxt->rex_bits & REX_B ? 8 : 0); ctxt->modrm_mod = (ctxt->modrm & 0xc0) >> 6; ctxt->modrm_reg |= (ctxt->modrm & 0x38) >> 3; @@ -1132,24 +1146,7 @@ static int decode_modrm(struct x86_emulate_ctxt *ctxt, ctxt->modrm_seg = VCPU_SREG_DS; if (ctxt->modrm_mod == 3 || (ctxt->d & NoMod)) { - op->type = OP_REG; - op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; - op->addr.reg = decode_register(ctxt, ctxt->modrm_rm, - ctxt->d & ByteOp); - if (ctxt->d & Sse) { - op->type = OP_XMM; - op->bytes = 16; - op->addr.xmm = ctxt->modrm_rm; - kvm_read_sse_reg(ctxt->modrm_rm, &op->vec_val); - return rc; - } - if (ctxt->d & Mmx) { - op->type = OP_MM; - op->bytes = 8; - op->addr.mm = ctxt->modrm_rm & 7; - return rc; - } - fetch_register_operand(op); + __decode_register_operand(ctxt, op, ctxt->modrm_rm); return rc; } @@ -1783,7 +1780,15 @@ static int writeback(struct x86_emulate_ctxt *ctxt, struct operand *op) op->data, op->bytes * op->count); case OP_XMM: - kvm_write_sse_reg(op->addr.xmm, &op->vec_val); + if (!(ctxt->d & Avx)) { + kvm_write_sse_reg(op->addr.xmm, &op->vec_val); + break; + } + /* full YMM write but with high bytes cleared */ + memset(op->valptr + 16, 0, 16); + fallthrough; + case OP_YMM: + kvm_write_avx_reg(op->addr.xmm, &op->vec_val2); break; case OP_MM: kvm_write_mmx_reg(op->addr.mm, &op->mm_val); @@ -2466,7 +2471,7 @@ static int em_sysexit(struct x86_emulate_ctxt *ctxt) setup_syscalls_segments(&cs, &ss); - if ((ctxt->rex_prefix & 0x8) != 0x0) + if (ctxt->rex_bits & REX_W) usermode = X86EMUL_MODE_PROT64; else usermode = X86EMUL_MODE_PROT32; @@ -3958,6 +3963,8 @@ static int check_perm_out(struct x86_emulate_ctxt *ctxt) I2bv(((_f) | DstReg | SrcMem | ModRM) & ~Lock, _e), \ I2bv(((_f) & ~Lock) | DstAcc | SrcImm, _e) +static const struct opcode ud = I(SrcNone, emulate_ud); + static const struct opcode group7_rm0[] = { N, I(SrcNone | Priv | EmulateOnUD, em_hypercall), @@ -4114,7 +4121,7 @@ static const struct group_dual group15 = { { } }; static const struct gprefix pfx_0f_6f_0f_7f = { - I(Mmx, em_mov), I(Sse | Aligned, em_mov), N, I(Sse | Unaligned, em_mov), + I(Mmx, em_mov), I(Sse | Avx | Aligned, em_mov), N, I(Sse | Avx | Unaligned, em_mov), }; static const struct instr_dual instr_dual_0f_2b = { @@ -4133,8 +4140,8 @@ static const struct gprefix pfx_0f_28_0f_29 = { I(Aligned, em_mov), I(Aligned, em_mov), N, N, }; -static const struct gprefix pfx_0f_e7 = { - N, I(Sse, em_mov), N, N, +static const struct gprefix pfx_0f_e7_0f_38_2a = { + N, I(Sse | Avx, em_mov), N, N, }; static const struct escape escape_d9 = { { @@ -4347,8 +4354,8 @@ static const struct opcode twobyte_table[256] = { DI(ImplicitOps | Priv, invd), DI(ImplicitOps | Priv, wbinvd), N, N, N, D(ImplicitOps | ModRM | SrcMem | NoAccess), N, N, /* 0x10 - 0x1F */ - GP(ModRM | DstReg | SrcMem | Mov | Sse, &pfx_0f_10_0f_11), - GP(ModRM | DstMem | SrcReg | Mov | Sse, &pfx_0f_10_0f_11), + GP(ModRM | DstReg | SrcMem | Mov | Sse | Avx, &pfx_0f_10_0f_11), + GP(ModRM | DstMem | SrcReg | Mov | Sse | Avx, &pfx_0f_10_0f_11), N, N, N, N, N, N, D(ImplicitOps | ModRM | SrcMem | NoAccess), /* 4 * prefetch + 4 * reserved NOP */ D(ImplicitOps | ModRM | SrcMem | NoAccess), N, N, @@ -4364,9 +4371,9 @@ static const struct opcode twobyte_table[256] = { IIP(ModRM | SrcMem | Priv | Op3264 | NoMod, em_dr_write, dr_write, check_dr_write), N, N, N, N, - GP(ModRM | DstReg | SrcMem | Mov | Sse, &pfx_0f_28_0f_29), - GP(ModRM | DstMem | SrcReg | Mov | Sse, &pfx_0f_28_0f_29), - N, GP(ModRM | DstMem | SrcReg | Mov | Sse, &pfx_0f_2b), + GP(ModRM | DstReg | SrcMem | Mov | Sse | Avx, &pfx_0f_28_0f_29), + GP(ModRM | DstMem | SrcReg | Mov | Sse | Avx, &pfx_0f_28_0f_29), + N, GP(ModRM | DstMem | SrcReg | Mov | Sse | Avx, &pfx_0f_2b), N, N, N, N, /* 0x30 - 0x3F */ II(ImplicitOps | Priv, em_wrmsr, wrmsr), @@ -4431,7 +4438,7 @@ static const struct opcode twobyte_table[256] = { /* 0xD0 - 0xDF */ N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, /* 0xE0 - 0xEF */ - N, N, N, N, N, N, N, GP(SrcReg | DstMem | ModRM | Mov, &pfx_0f_e7), + N, N, N, N, N, N, N, GP(SrcReg | DstMem | ModRM | Mov, &pfx_0f_e7_0f_38_2a), N, N, N, N, N, N, N, N, /* 0xF0 - 0xFF */ N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N @@ -4458,8 +4465,13 @@ static const struct gprefix three_byte_0f_38_f1 = { * byte. */ static const struct opcode opcode_map_0f_38[256] = { - /* 0x00 - 0x7f */ - X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), + /* 0x00 - 0x1f */ + X16(N), X16(N), + /* 0x20 - 0x2f */ + X8(N), + X2(N), GP(SrcReg | DstMem | ModRM | Mov | Aligned, &pfx_0f_e7_0f_38_2a), N, N, N, N, N, + /* 0x30 - 0x7f */ + X16(N), X16(N), X16(N), X16(N), X16(N), /* 0x80 - 0xef */ X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), /* 0xf0 - 0xf1 */ @@ -4618,14 +4630,12 @@ static int decode_operand(struct x86_emulate_ctxt *ctxt, struct operand *op, op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes; op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RAX); fetch_register_operand(op); - op->orig_val = op->val; break; case OpAccLo: op->type = OP_REG; op->bytes = (ctxt->d & ByteOp) ? 2 : ctxt->op_bytes; op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RAX); fetch_register_operand(op); - op->orig_val = op->val; break; case OpAccHi: if (ctxt->d & ByteOp) { @@ -4636,7 +4646,6 @@ static int decode_operand(struct x86_emulate_ctxt *ctxt, struct operand *op, op->bytes = ctxt->op_bytes; op->addr.reg = reg_rmw(ctxt, VCPU_REGS_RDX); fetch_register_operand(op); - op->orig_val = op->val; break; case OpDI: op->type = OP_MEM; @@ -4755,12 +4764,87 @@ done: return rc; } +static int x86_decode_avx(struct x86_emulate_ctxt *ctxt, + u8 vex_1st, u8 vex_2nd, struct opcode *opcode) +{ + u8 vex_3rd, map, pp, l, v; + int rc = X86EMUL_CONTINUE; + + if (ctxt->rep_prefix || ctxt->op_prefix || ctxt->rex_prefix) + goto ud; + + if (vex_1st == 0xc5) { + /* Expand RVVVVlpp to VEX3 format */ + vex_3rd = vex_2nd & ~0x80; /* VVVVlpp from VEX2, w=0 */ + vex_2nd = (vex_2nd & 0x80) | 0x61; /* R from VEX2, X=1 B=1 mmmmm=00001 */ + } else { + vex_3rd = insn_fetch(u8, ctxt); + } + + /* vex_2nd = RXBmmmmm, vex_3rd = wVVVVlpp. Fix polarity */ + vex_2nd ^= 0xE0; /* binary 11100000 */ + vex_3rd ^= 0x78; /* binary 01111000 */ + + ctxt->rex_prefix = REX_PREFIX; + ctxt->rex_bits = (vex_2nd & 0xE0) >> 5; /* RXB */ + ctxt->rex_bits |= (vex_3rd & 0x80) >> 4; /* w */ + if (ctxt->rex_bits && ctxt->mode != X86EMUL_MODE_PROT64) + goto ud; + + map = vex_2nd & 0x1f; + v = (vex_3rd >> 3) & 0xf; + l = vex_3rd & 0x4; + pp = vex_3rd & 0x3; + + ctxt->b = insn_fetch(u8, ctxt); + switch (map) { + case 1: + ctxt->opcode_len = 2; + *opcode = twobyte_table[ctxt->b]; + break; + case 2: + ctxt->opcode_len = 3; + *opcode = opcode_map_0f_38[ctxt->b]; + break; + case 3: + /* no 0f 3a instructions are supported yet */ + return X86EMUL_UNHANDLEABLE; + default: + goto ud; + } + + /* + * No three operand instructions are supported yet; those that + * *are* marked with the Avx flag reserve the VVVV flag. + */ + if (v) + goto ud; + + if (l) + ctxt->op_bytes = 32; + else + ctxt->op_bytes = 16; + + switch (pp) { + case 0: break; + case 1: ctxt->op_prefix = true; break; + case 2: ctxt->rep_prefix = 0xf3; break; + case 3: ctxt->rep_prefix = 0xf2; break; + } + +done: + return rc; +ud: + *opcode = ud; + return rc; +} + int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len, int emulation_type) { int rc = X86EMUL_CONTINUE; int mode = ctxt->mode; int def_op_bytes, def_ad_bytes, goffset, simd_prefix; - bool op_prefix = false; + bool vex_prefix = false; bool has_seg_override = false; struct opcode opcode; u16 dummy; @@ -4812,7 +4896,7 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len, int for (;;) { switch (ctxt->b = insn_fetch(u8, ctxt)) { case 0x66: /* operand-size override */ - op_prefix = true; + ctxt->op_prefix = true; /* switch between 2/4 bytes */ ctxt->op_bytes = def_op_bytes ^ 6; break; @@ -4851,7 +4935,8 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len, int case 0x40 ... 0x4f: /* REX */ if (mode != X86EMUL_MODE_PROT64) goto done_prefixes; - ctxt->rex_prefix = ctxt->b; + ctxt->rex_prefix = REX_PREFIX; + ctxt->rex_bits = ctxt->b & 0xf; continue; case 0xf0: /* LOCK */ ctxt->lock_prefix = 1; @@ -4865,20 +4950,33 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len, int } /* Any legacy prefix after a REX prefix nullifies its effect. */ - - ctxt->rex_prefix = 0; + ctxt->rex_prefix = REX_NONE; + ctxt->rex_bits = 0; } done_prefixes: /* REX prefix. */ - if (ctxt->rex_prefix & 8) - ctxt->op_bytes = 8; /* REX.W */ + if (ctxt->rex_bits & REX_W) + ctxt->op_bytes = 8; /* Opcode byte(s). */ - opcode = opcode_table[ctxt->b]; - /* Two-byte opcode? */ - if (ctxt->b == 0x0f) { + if (ctxt->b == 0xc4 || ctxt->b == 0xc5) { + /* VEX or LDS/LES */ + u8 vex_2nd = insn_fetch(u8, ctxt); + if (mode != X86EMUL_MODE_PROT64 && (vex_2nd & 0xc0) != 0xc0) { + opcode = opcode_table[ctxt->b]; + ctxt->modrm = vex_2nd; + /* the Mod/RM byte has been fetched already! */ + goto done_modrm; + } + + vex_prefix = true; + rc = x86_decode_avx(ctxt, ctxt->b, vex_2nd, &opcode); + if (rc != X86EMUL_CONTINUE) + goto done; + } else if (ctxt->b == 0x0f) { + /* Two- or three-byte opcode */ ctxt->opcode_len = 2; ctxt->b = insn_fetch(u8, ctxt); opcode = twobyte_table[ctxt->b]; @@ -4889,18 +4987,16 @@ done_prefixes: ctxt->b = insn_fetch(u8, ctxt); opcode = opcode_map_0f_38[ctxt->b]; } + } else { + /* Opcode byte(s). */ + opcode = opcode_table[ctxt->b]; } - ctxt->d = opcode.flags; - if (ctxt->d & ModRM) + if (opcode.flags & ModRM) ctxt->modrm = insn_fetch(u8, ctxt); - /* vex-prefix instructions are not implemented */ - if (ctxt->opcode_len == 1 && (ctxt->b == 0xc5 || ctxt->b == 0xc4) && - (mode == X86EMUL_MODE_PROT64 || (ctxt->modrm & 0xc0) == 0xc0)) { - ctxt->d = NotImpl; - } - +done_modrm: + ctxt->d = opcode.flags; while (ctxt->d & GroupMask) { switch (ctxt->d & GroupMask) { case Group: @@ -4919,9 +5015,9 @@ done_prefixes: opcode = opcode.u.group[goffset]; break; case Prefix: - if (ctxt->rep_prefix && op_prefix) + if (ctxt->rep_prefix && ctxt->op_prefix) return EMULATION_FAILED; - simd_prefix = op_prefix ? 0x66 : ctxt->rep_prefix; + simd_prefix = ctxt->op_prefix ? 0x66 : ctxt->rep_prefix; switch (simd_prefix) { case 0x00: opcode = opcode.u.gprefix->pfx_no; break; case 0x66: opcode = opcode.u.gprefix->pfx_66; break; @@ -4966,6 +5062,19 @@ done_prefixes: if (ctxt->d == 0) return EMULATION_FAILED; + if (unlikely(vex_prefix)) { + /* + * Only specifically marked instructions support VEX. Since many + * instructions support it but are not annotated, return not implemented + * rather than #UD. + */ + if (!(ctxt->d & Avx)) + return EMULATION_FAILED; + + if (!(ctxt->d & AlignMask)) + ctxt->d |= Unaligned; + } + ctxt->execute = opcode.u.execute; /* @@ -5036,8 +5145,10 @@ done_prefixes: if ((ctxt->d & No16) && ctxt->op_bytes == 2) ctxt->op_bytes = 4; - if (ctxt->d & Sse) - ctxt->op_bytes = 16; + if (vex_prefix) + ; + else if (ctxt->d & Sse) + ctxt->op_bytes = 16, ctxt->d &= ~Avx; else if (ctxt->d & Mmx) ctxt->op_bytes = 8; } @@ -5137,8 +5248,10 @@ void init_decode_cache(struct x86_emulate_ctxt *ctxt) { /* Clear fields that are set conditionally but read without a guard. */ ctxt->rip_relative = false; - ctxt->rex_prefix = 0; + ctxt->rex_prefix = REX_NONE; + ctxt->rex_bits = 0; ctxt->lock_prefix = 0; + ctxt->op_prefix = false; ctxt->rep_prefix = 0; ctxt->regs_valid = 0; ctxt->regs_dirty = 0; @@ -5168,20 +5281,34 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt, bool check_intercepts) } if (unlikely(ctxt->d & - (No64|Undefined|Sse|Mmx|Intercept|CheckPerm|Priv|Prot|String))) { + (No64|Undefined|Avx|Sse|Mmx|Intercept|CheckPerm|Priv|Prot|String))) { if ((ctxt->mode == X86EMUL_MODE_PROT64 && (ctxt->d & No64)) || (ctxt->d & Undefined)) { rc = emulate_ud(ctxt); goto done; } - if (((ctxt->d & (Sse|Mmx)) && ((ops->get_cr(ctxt, 0) & X86_CR0_EM))) - || ((ctxt->d & Sse) && !(ops->get_cr(ctxt, 4) & X86_CR4_OSFXSR))) { + if ((ctxt->d & (Avx|Sse|Mmx)) && ((ops->get_cr(ctxt, 0) & X86_CR0_EM))) { rc = emulate_ud(ctxt); goto done; } - if ((ctxt->d & (Sse|Mmx)) && (ops->get_cr(ctxt, 0) & X86_CR0_TS)) { + if (ctxt->d & Avx) { + u64 xcr = 0; + if (!(ops->get_cr(ctxt, 4) & X86_CR4_OSXSAVE) + || ops->get_xcr(ctxt, 0, &xcr) + || !(xcr & XFEATURE_MASK_YMM)) { + rc = emulate_ud(ctxt); + goto done; + } + } else if (ctxt->d & Sse) { + if (!(ops->get_cr(ctxt, 4) & X86_CR4_OSFXSR)) { + rc = emulate_ud(ctxt); + goto done; + } + } + + if ((ctxt->d & (Avx|Sse|Mmx)) && (ops->get_cr(ctxt, 0) & X86_CR0_TS)) { rc = emulate_nm(ctxt); goto done; } diff --git a/arch/x86/kvm/fpu.h b/arch/x86/kvm/fpu.h index 3ba12888bf66..f898781b6a06 100644 --- a/arch/x86/kvm/fpu.h +++ b/arch/x86/kvm/fpu.h @@ -15,6 +15,58 @@ typedef u32 __attribute__((vector_size(16))) sse128_t; #define sse128_l3(x) ({ __sse128_u t; t.vec = x; t.as_u32[3]; }) #define sse128(lo, hi) ({ __sse128_u t; t.as_u64[0] = lo; t.as_u64[1] = hi; t.vec; }) +typedef u32 __attribute__((vector_size(32))) avx256_t; + +static inline void _kvm_read_avx_reg(int reg, avx256_t *data) +{ + switch (reg) { + case 0: asm("vmovdqa %%ymm0, %0" : "=m"(*data)); break; + case 1: asm("vmovdqa %%ymm1, %0" : "=m"(*data)); break; + case 2: asm("vmovdqa %%ymm2, %0" : "=m"(*data)); break; + case 3: asm("vmovdqa %%ymm3, %0" : "=m"(*data)); break; + case 4: asm("vmovdqa %%ymm4, %0" : "=m"(*data)); break; + case 5: asm("vmovdqa %%ymm5, %0" : "=m"(*data)); break; + case 6: asm("vmovdqa %%ymm6, %0" : "=m"(*data)); break; + case 7: asm("vmovdqa %%ymm7, %0" : "=m"(*data)); break; +#ifdef CONFIG_X86_64 + case 8: asm("vmovdqa %%ymm8, %0" : "=m"(*data)); break; + case 9: asm("vmovdqa %%ymm9, %0" : "=m"(*data)); break; + case 10: asm("vmovdqa %%ymm10, %0" : "=m"(*data)); break; + case 11: asm("vmovdqa %%ymm11, %0" : "=m"(*data)); break; + case 12: asm("vmovdqa %%ymm12, %0" : "=m"(*data)); break; + case 13: asm("vmovdqa %%ymm13, %0" : "=m"(*data)); break; + case 14: asm("vmovdqa %%ymm14, %0" : "=m"(*data)); break; + case 15: asm("vmovdqa %%ymm15, %0" : "=m"(*data)); break; +#endif + default: BUG(); + } +} + +static inline void _kvm_write_avx_reg(int reg, const avx256_t *data) +{ + switch (reg) { + case 0: asm("vmovdqa %0, %%ymm0" : : "m"(*data)); break; + case 1: asm("vmovdqa %0, %%ymm1" : : "m"(*data)); break; + case 2: asm("vmovdqa %0, %%ymm2" : : "m"(*data)); break; + case 3: asm("vmovdqa %0, %%ymm3" : : "m"(*data)); break; + case 4: asm("vmovdqa %0, %%ymm4" : : "m"(*data)); break; + case 5: asm("vmovdqa %0, %%ymm5" : : "m"(*data)); break; + case 6: asm("vmovdqa %0, %%ymm6" : : "m"(*data)); break; + case 7: asm("vmovdqa %0, %%ymm7" : : "m"(*data)); break; +#ifdef CONFIG_X86_64 + case 8: asm("vmovdqa %0, %%ymm8" : : "m"(*data)); break; + case 9: asm("vmovdqa %0, %%ymm9" : : "m"(*data)); break; + case 10: asm("vmovdqa %0, %%ymm10" : : "m"(*data)); break; + case 11: asm("vmovdqa %0, %%ymm11" : : "m"(*data)); break; + case 12: asm("vmovdqa %0, %%ymm12" : : "m"(*data)); break; + case 13: asm("vmovdqa %0, %%ymm13" : : "m"(*data)); break; + case 14: asm("vmovdqa %0, %%ymm14" : : "m"(*data)); break; + case 15: asm("vmovdqa %0, %%ymm15" : : "m"(*data)); break; +#endif + default: BUG(); + } +} + static inline void _kvm_read_sse_reg(int reg, sse128_t *data) { switch (reg) { @@ -109,6 +161,20 @@ static inline void kvm_fpu_put(void) fpregs_unlock(); } +static inline void kvm_read_avx_reg(int reg, avx256_t *data) +{ + kvm_fpu_get(); + _kvm_read_avx_reg(reg, data); + kvm_fpu_put(); +} + +static inline void kvm_write_avx_reg(int reg, const avx256_t *data) +{ + kvm_fpu_get(); + _kvm_write_avx_reg(reg, data); + kvm_fpu_put(); +} + static inline void kvm_read_sse_reg(int reg, sse128_t *data) { kvm_fpu_get(); diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 38595ecb990d..de92292eb1f5 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1568,7 +1568,7 @@ static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host) * only, there can be valuable data in the rest which needs * to be preserved e.g. on migration. */ - if (__put_user(0, (u32 __user *)addr)) + if (put_user(0, (u32 __user *)addr)) return 1; hv_vcpu->hv_vapic = data; kvm_vcpu_mark_page_dirty(vcpu, gfn); diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h index 7b5ddb787a25..fb3dab4b5a53 100644 --- a/arch/x86/kvm/kvm_emulate.h +++ b/arch/x86/kvm/kvm_emulate.h @@ -237,6 +237,7 @@ struct x86_emulate_ops { bool (*is_smm)(struct x86_emulate_ctxt *ctxt); int (*leave_smm)(struct x86_emulate_ctxt *ctxt); void (*triple_fault)(struct x86_emulate_ctxt *ctxt); + int (*get_xcr)(struct x86_emulate_ctxt *ctxt, u32 index, u64 *xcr); int (*set_xcr)(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr); gva_t (*get_untagged_addr)(struct x86_emulate_ctxt *ctxt, gva_t addr, @@ -248,7 +249,7 @@ struct x86_emulate_ops { /* Type, address-of, and value of an instruction's operand. */ struct operand { - enum { OP_REG, OP_MEM, OP_MEM_STR, OP_IMM, OP_XMM, OP_MM, OP_NONE } type; + enum { OP_REG, OP_MEM, OP_MEM_STR, OP_IMM, OP_XMM, OP_YMM, OP_MM, OP_NONE } type; unsigned int bytes; unsigned int count; union { @@ -267,11 +268,12 @@ struct operand { union { unsigned long val; u64 val64; - char valptr[sizeof(sse128_t)]; + char valptr[sizeof(avx256_t)]; sse128_t vec_val; + avx256_t vec_val2; u64 mm_val; void *data; - }; + } __aligned(32); }; #define X86_MAX_INSTRUCTION_LENGTH 15 @@ -317,6 +319,14 @@ typedef void (*fastop_t)(struct fastop *); #define NR_EMULATOR_GPRS 8 #endif +/* + * Distinguish between no prefix, REX, or in the future REX2. + */ +enum rex_type { + REX_NONE, + REX_PREFIX, +}; + struct x86_emulate_ctxt { void *vcpu; const struct x86_emulate_ops *ops; @@ -348,6 +358,7 @@ struct x86_emulate_ctxt { u8 opcode_len; u8 b; u8 intercept; + bool op_prefix; u8 op_bytes; u8 ad_bytes; union { @@ -357,7 +368,8 @@ struct x86_emulate_ctxt { int (*check_perm)(struct x86_emulate_ctxt *ctxt); bool rip_relative; - u8 rex_prefix; + enum rex_type rex_prefix; + u8 rex_bits; u8 lock_prefix; u8 rep_prefix; /* bitmaps of registers in _regs[] that can be read */ diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 0ae7f913d782..1597dd0b0cc6 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -2126,23 +2126,41 @@ static bool set_target_expiration(struct kvm_lapic *apic, u32 count_reg) static void advance_periodic_target_expiration(struct kvm_lapic *apic) { + struct kvm_timer *ktimer = &apic->lapic_timer; ktime_t now = ktime_get(); u64 tscl = rdtsc(); ktime_t delta; /* - * Synchronize both deadlines to the same time source or - * differences in the periods (caused by differences in the - * underlying clocks or numerical approximation errors) will - * cause the two to drift apart over time as the errors - * accumulate. + * Use kernel time as the time source for both the hrtimer deadline and + * TSC-based deadline so that they stay synchronized. Computing each + * deadline independently will cause the two deadlines to drift apart + * over time as differences in the periods accumulate, e.g. due to + * differences in the underlying clocks or numerical approximation errors. */ - apic->lapic_timer.target_expiration = - ktime_add_ns(apic->lapic_timer.target_expiration, - apic->lapic_timer.period); - delta = ktime_sub(apic->lapic_timer.target_expiration, now); - apic->lapic_timer.tscdeadline = kvm_read_l1_tsc(apic->vcpu, tscl) + - nsec_to_cycles(apic->vcpu, delta); + ktimer->target_expiration = ktime_add_ns(ktimer->target_expiration, + ktimer->period); + + /* + * If the new expiration is in the past, e.g. because userspace stopped + * running the VM for an extended duration, then force the expiration + * to "now" and don't try to play catch-up with the missed events. KVM + * will only deliver a single interrupt regardless of how many events + * are pending, i.e. restarting the timer with an expiration in the + * past will do nothing more than waste host cycles, and can even lead + * to a hard lockup in extreme cases. + */ + if (ktime_before(ktimer->target_expiration, now)) + ktimer->target_expiration = now; + + /* + * Note, ensuring the expiration isn't in the past also prevents delta + * from going negative, which could cause the TSC deadline to become + * excessively large due to it an unsigned value. + */ + delta = ktime_sub(ktimer->target_expiration, now); + ktimer->tscdeadline = kvm_read_l1_tsc(apic->vcpu, tscl) + + nsec_to_cycles(apic->vcpu, delta); } static void start_sw_period(struct kvm_lapic *apic) @@ -2970,9 +2988,9 @@ static enum hrtimer_restart apic_timer_fn(struct hrtimer *data) apic_timer_expired(apic, true); - if (lapic_is_periodic(apic)) { + if (lapic_is_periodic(apic) && !WARN_ON_ONCE(!apic->lapic_timer.period)) { advance_periodic_target_expiration(apic); - hrtimer_add_expires_ns(&ktimer->timer, ktimer->period); + hrtimer_set_expires(&ktimer->timer, ktimer->target_expiration); return HRTIMER_RESTART; } else return HRTIMER_NORESTART; diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index f63074048ec6..830f46145692 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -235,8 +235,6 @@ static inline u8 permission_fault(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, return -(u32)fault & errcode; } -bool kvm_mmu_may_ignore_guest_pat(struct kvm *kvm); - int kvm_mmu_post_init_vm(struct kvm *kvm); void kvm_mmu_pre_destroy_vm(struct kvm *kvm); @@ -257,8 +255,7 @@ extern bool tdp_mmu_enabled; #define tdp_mmu_enabled false #endif -bool kvm_tdp_mmu_gpa_is_mapped(struct kvm_vcpu *vcpu, u64 gpa); -int kvm_tdp_map_page(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code, u8 *level); +int kvm_tdp_mmu_map_private_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, kvm_pfn_t pfn); static inline bool kvm_memslots_have_rmaps(struct kvm *kvm) { diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 667d66cf76d5..02c450686b4a 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -4859,7 +4859,7 @@ int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code, */ BUILD_BUG_ON(lower_32_bits(PFERR_SYNTHETIC_MASK)); - vcpu->arch.l1tf_flush_l1d = true; + kvm_request_l1tf_flush_l1d(); if (!flags) { trace_kvm_page_fault(vcpu, fault_address, error_code); @@ -4924,7 +4924,8 @@ int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) return direct_page_fault(vcpu, fault); } -int kvm_tdp_map_page(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code, u8 *level) +static int kvm_tdp_page_prefault(struct kvm_vcpu *vcpu, gpa_t gpa, + u64 error_code, u8 *level) { int r; @@ -4966,7 +4967,6 @@ int kvm_tdp_map_page(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code, u8 *level return -EIO; } } -EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_tdp_map_page); long kvm_arch_vcpu_pre_fault_memory(struct kvm_vcpu *vcpu, struct kvm_pre_fault_memory *range) @@ -5002,7 +5002,7 @@ long kvm_arch_vcpu_pre_fault_memory(struct kvm_vcpu *vcpu, * Shadow paging uses GVA for kvm page fault, so restrict to * two-dimensional paging. */ - r = kvm_tdp_map_page(vcpu, range->gpa | direct_bits, error_code, &level); + r = kvm_tdp_page_prefault(vcpu, range->gpa | direct_bits, error_code, &level); if (r < 0) return r; @@ -5014,6 +5014,86 @@ long kvm_arch_vcpu_pre_fault_memory(struct kvm_vcpu *vcpu, return min(range->size, end - range->gpa); } +#ifdef CONFIG_KVM_GUEST_MEMFD +static void kvm_assert_gmem_invalidate_lock_held(struct kvm_memory_slot *slot) +{ +#ifdef CONFIG_PROVE_LOCKING + if (WARN_ON_ONCE(!kvm_slot_has_gmem(slot)) || + WARN_ON_ONCE(!slot->gmem.file) || + WARN_ON_ONCE(!file_count(slot->gmem.file))) + return; + + lockdep_assert_held(&file_inode(slot->gmem.file)->i_mapping->invalidate_lock); +#endif +} + +int kvm_tdp_mmu_map_private_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, kvm_pfn_t pfn) +{ + struct kvm_page_fault fault = { + .addr = gfn_to_gpa(gfn), + .error_code = PFERR_GUEST_FINAL_MASK | PFERR_PRIVATE_ACCESS, + .prefetch = true, + .is_tdp = true, + .nx_huge_page_workaround_enabled = is_nx_huge_page_enabled(vcpu->kvm), + + .max_level = PG_LEVEL_4K, + .req_level = PG_LEVEL_4K, + .goal_level = PG_LEVEL_4K, + .is_private = true, + + .gfn = gfn, + .slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn), + .pfn = pfn, + .map_writable = true, + }; + struct kvm *kvm = vcpu->kvm; + int r; + + lockdep_assert_held(&kvm->slots_lock); + + /* + * Mapping a pre-determined private pfn is intended only for use when + * populating a guest_memfd instance. Assert that the slot is backed + * by guest_memfd and that the gmem instance's invalidate_lock is held. + */ + kvm_assert_gmem_invalidate_lock_held(fault.slot); + + if (KVM_BUG_ON(!tdp_mmu_enabled, kvm)) + return -EIO; + + if (kvm_gfn_is_write_tracked(kvm, fault.slot, fault.gfn)) + return -EPERM; + + r = kvm_mmu_reload(vcpu); + if (r) + return r; + + r = mmu_topup_memory_caches(vcpu, false); + if (r) + return r; + + do { + if (signal_pending(current)) + return -EINTR; + + if (kvm_test_request(KVM_REQ_VM_DEAD, vcpu)) + return -EIO; + + cond_resched(); + + guard(read_lock)(&kvm->mmu_lock); + + r = kvm_tdp_mmu_map(vcpu, &fault); + } while (r == RET_PF_RETRY); + + if (r != RET_PF_FIXED) + return -EIO; + + return 0; +} +EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_tdp_mmu_map_private_pfn); +#endif + static void nonpaging_init_context(struct kvm_mmu *context) { context->page_fault = nonpaging_page_fault; @@ -5997,7 +6077,6 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu) out: return r; } -EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_mmu_load); void kvm_mmu_unload(struct kvm_vcpu *vcpu) { @@ -6863,6 +6942,7 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) write_unlock(&kvm->mmu_lock); } +EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_zap_gfn_range); static bool slot_rmap_write_protect(struct kvm *kvm, struct kvm_rmap_head *rmap_head, @@ -7204,7 +7284,6 @@ restart: return need_tlb_flush; } -EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_zap_gfn_range); static void kvm_rmap_zap_collapsible_sptes(struct kvm *kvm, const struct kvm_memory_slot *slot) @@ -7364,6 +7443,9 @@ void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm, u64 gen) { WARN_ON_ONCE(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS); + if (!enable_mmio_caching) + return; + gen &= MMIO_SPTE_GEN_MASK; /* diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h index ed5c01df21ba..73cdcbccc89e 100644 --- a/arch/x86/kvm/mmu/mmu_internal.h +++ b/arch/x86/kvm/mmu/mmu_internal.h @@ -39,16 +39,6 @@ #define INVALID_PAE_ROOT 0 #define IS_VALID_PAE_ROOT(x) (!!(x)) -static inline hpa_t kvm_mmu_get_dummy_root(void) -{ - return my_zero_pfn(0) << PAGE_SHIFT; -} - -static inline bool kvm_mmu_is_dummy_root(hpa_t shadow_page) -{ - return is_zero_pfn(shadow_page >> PAGE_SHIFT); -} - typedef u64 __rcu *tdp_ptep_t; struct kvm_mmu_page { diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h index ed762bb4b007..901cd2bd40b8 100644 --- a/arch/x86/kvm/mmu/paging_tmpl.h +++ b/arch/x86/kvm/mmu/paging_tmpl.h @@ -402,7 +402,7 @@ retry_walk: goto error; ptep_user = (pt_element_t __user *)((void *)host_addr + offset); - if (unlikely(__get_user(pte, ptep_user))) + if (unlikely(get_user(pte, ptep_user))) goto error; walker->ptep_user[walker->level - 1] = ptep_user; diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c index 37647afde7d3..85a0473809b0 100644 --- a/arch/x86/kvm/mmu/spte.c +++ b/arch/x86/kvm/mmu/spte.c @@ -292,7 +292,7 @@ bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, mark_page_dirty_in_slot(vcpu->kvm, slot, gfn); } - if (static_branch_unlikely(&cpu_buf_vm_clear) && + if (cpu_feature_enabled(X86_FEATURE_CLEAR_CPU_BUF_VM_MMIO) && !kvm_vcpu_can_access_host_mmio(vcpu) && kvm_is_mmio_pfn(pfn, &is_host_mmio)) kvm_track_host_mmio_mapping(vcpu); diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h index 3133f066927e..91ce29fd6f1b 100644 --- a/arch/x86/kvm/mmu/spte.h +++ b/arch/x86/kvm/mmu/spte.h @@ -246,6 +246,16 @@ static inline int spte_index(u64 *sptep) */ extern u64 __read_mostly shadow_nonpresent_or_rsvd_lower_gfn_mask; +static inline hpa_t kvm_mmu_get_dummy_root(void) +{ + return my_zero_pfn(0) << PAGE_SHIFT; +} + +static inline bool kvm_mmu_is_dummy_root(hpa_t shadow_page) +{ + return is_zero_pfn(shadow_page >> PAGE_SHIFT); +} + static inline struct kvm_mmu_page *to_shadow_page(hpa_t shadow_page) { struct page *page = pfn_to_page((shadow_page) >> PAGE_SHIFT); diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index c5734ca5c17d..9c26038f6b77 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -362,9 +362,6 @@ static void tdp_mmu_unlink_sp(struct kvm *kvm, struct kvm_mmu_page *sp) static void remove_external_spte(struct kvm *kvm, gfn_t gfn, u64 old_spte, int level) { - kvm_pfn_t old_pfn = spte_to_pfn(old_spte); - int ret; - /* * External (TDX) SPTEs are limited to PG_LEVEL_4K, and external * PTs are removed in a special order, involving free_external_spt(). @@ -377,9 +374,8 @@ static void remove_external_spte(struct kvm *kvm, gfn_t gfn, u64 old_spte, /* Zapping leaf spte is allowed only when write lock is held. */ lockdep_assert_held_write(&kvm->mmu_lock); - /* Because write lock is held, operation should success. */ - ret = kvm_x86_call(remove_external_spte)(kvm, gfn, level, old_pfn); - KVM_BUG_ON(ret, kvm); + + kvm_x86_call(remove_external_spte)(kvm, gfn, level, old_spte); } /** @@ -519,7 +515,6 @@ static int __must_check set_external_spte_present(struct kvm *kvm, tdp_ptep_t sp bool was_present = is_shadow_present_pte(old_spte); bool is_present = is_shadow_present_pte(new_spte); bool is_leaf = is_present && is_last_spte(new_spte, level); - kvm_pfn_t new_pfn = spte_to_pfn(new_spte); int ret = 0; KVM_BUG_ON(was_present, kvm); @@ -538,7 +533,7 @@ static int __must_check set_external_spte_present(struct kvm *kvm, tdp_ptep_t sp * external page table, or leaf. */ if (is_leaf) { - ret = kvm_x86_call(set_external_spte)(kvm, gfn, level, new_pfn); + ret = kvm_x86_call(set_external_spte)(kvm, gfn, level, new_spte); } else { void *external_spt = get_external_spt(gfn, new_spte, level); @@ -1273,6 +1268,8 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) struct kvm_mmu_page *sp; int ret = RET_PF_RETRY; + KVM_MMU_WARN_ON(!root || root->role.invalid); + kvm_mmu_hugepage_adjust(vcpu, fault); trace_kvm_mmu_spte_requested(fault); @@ -1939,13 +1936,16 @@ bool kvm_tdp_mmu_write_protect_gfn(struct kvm *kvm, * * Must be called between kvm_tdp_mmu_walk_lockless_{begin,end}. */ -static int __kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, - struct kvm_mmu_page *root) +int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, + int *root_level) { + struct kvm_mmu_page *root = root_to_sp(vcpu->arch.mmu->root.hpa); struct tdp_iter iter; gfn_t gfn = addr >> PAGE_SHIFT; int leaf = -1; + *root_level = vcpu->arch.mmu->root_role.level; + for_each_tdp_pte(iter, vcpu->kvm, root, gfn, gfn + 1) { leaf = iter.level; sptes[leaf] = iter.old_spte; @@ -1954,36 +1954,6 @@ static int __kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, return leaf; } -int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, - int *root_level) -{ - struct kvm_mmu_page *root = root_to_sp(vcpu->arch.mmu->root.hpa); - *root_level = vcpu->arch.mmu->root_role.level; - - return __kvm_tdp_mmu_get_walk(vcpu, addr, sptes, root); -} - -bool kvm_tdp_mmu_gpa_is_mapped(struct kvm_vcpu *vcpu, u64 gpa) -{ - struct kvm *kvm = vcpu->kvm; - bool is_direct = kvm_is_addr_direct(kvm, gpa); - hpa_t root = is_direct ? vcpu->arch.mmu->root.hpa : - vcpu->arch.mmu->mirror_root_hpa; - u64 sptes[PT64_ROOT_MAX_LEVEL + 1], spte; - int leaf; - - lockdep_assert_held(&kvm->mmu_lock); - rcu_read_lock(); - leaf = __kvm_tdp_mmu_get_walk(vcpu, gpa, sptes, root_to_sp(root)); - rcu_read_unlock(); - if (leaf < 0) - return false; - - spte = sptes[leaf]; - return is_shadow_present_pte(spte) && is_last_spte(spte, leaf); -} -EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_tdp_mmu_gpa_is_mapped); - /* * Returns the last level spte pointer of the shadow page walk for the given * gpa, and sets *spte to the spte value. This spte may be non-preset. If no diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c index fef00546c885..6b77b2033208 100644 --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -106,7 +106,7 @@ static u32 next_vm_id = 0; static bool next_vm_id_wrapped = 0; static DEFINE_SPINLOCK(svm_vm_data_hash_lock); static bool x2avic_enabled; - +static u32 x2avic_max_physical_id; static void avic_set_x2apic_msr_interception(struct vcpu_svm *svm, bool intercept) @@ -158,12 +158,40 @@ static void avic_set_x2apic_msr_interception(struct vcpu_svm *svm, svm->x2avic_msrs_intercepted = intercept; } +static u32 __avic_get_max_physical_id(struct kvm *kvm, struct kvm_vcpu *vcpu) +{ + u32 arch_max; + + /* + * Return the largest size (x2APIC) when querying without a vCPU, e.g. + * to allocate the per-VM table.. + */ + if (x2avic_enabled && (!vcpu || apic_x2apic_mode(vcpu->arch.apic))) + arch_max = x2avic_max_physical_id; + else + arch_max = AVIC_MAX_PHYSICAL_ID; + + /* + * Despite its name, KVM_CAP_MAX_VCPU_ID represents the maximum APIC ID + * plus one, so the max possible APIC ID is one less than that. + */ + return min(kvm->arch.max_vcpu_ids - 1, arch_max); +} + +static u32 avic_get_max_physical_id(struct kvm_vcpu *vcpu) +{ + return __avic_get_max_physical_id(vcpu->kvm, vcpu); +} + static void avic_activate_vmcb(struct vcpu_svm *svm) { struct vmcb *vmcb = svm->vmcb01.ptr; + struct kvm_vcpu *vcpu = &svm->vcpu; vmcb->control.int_ctl &= ~(AVIC_ENABLE_MASK | X2APIC_MODE_MASK); + vmcb->control.avic_physical_id &= ~AVIC_PHYSICAL_MAX_INDEX_MASK; + vmcb->control.avic_physical_id |= avic_get_max_physical_id(vcpu); vmcb->control.int_ctl |= AVIC_ENABLE_MASK; @@ -176,7 +204,7 @@ static void avic_activate_vmcb(struct vcpu_svm *svm) */ if (x2avic_enabled && apic_x2apic_mode(svm->vcpu.arch.apic)) { vmcb->control.int_ctl |= X2APIC_MODE_MASK; - vmcb->control.avic_physical_id |= X2AVIC_MAX_PHYSICAL_ID; + /* Disabling MSR intercept for x2APIC registers */ avic_set_x2apic_msr_interception(svm, false); } else { @@ -186,8 +214,6 @@ static void avic_activate_vmcb(struct vcpu_svm *svm) */ kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, &svm->vcpu); - /* For xAVIC and hybrid-xAVIC modes */ - vmcb->control.avic_physical_id |= AVIC_MAX_PHYSICAL_ID; /* Enabling MSR intercept for x2APIC registers */ avic_set_x2apic_msr_interception(svm, true); } @@ -247,6 +273,30 @@ static int avic_ga_log_notifier(u32 ga_tag) return 0; } +static int avic_get_physical_id_table_order(struct kvm *kvm) +{ + /* Provision for the maximum physical ID supported in x2avic mode */ + return get_order((__avic_get_max_physical_id(kvm, NULL) + 1) * sizeof(u64)); +} + +int avic_alloc_physical_id_table(struct kvm *kvm) +{ + struct kvm_svm *kvm_svm = to_kvm_svm(kvm); + + if (!irqchip_in_kernel(kvm) || !enable_apicv) + return 0; + + if (kvm_svm->avic_physical_id_table) + return 0; + + kvm_svm->avic_physical_id_table = (void *)__get_free_pages(GFP_KERNEL_ACCOUNT | __GFP_ZERO, + avic_get_physical_id_table_order(kvm)); + if (!kvm_svm->avic_physical_id_table) + return -ENOMEM; + + return 0; +} + void avic_vm_destroy(struct kvm *kvm) { unsigned long flags; @@ -256,7 +306,8 @@ void avic_vm_destroy(struct kvm *kvm) return; free_page((unsigned long)kvm_svm->avic_logical_id_table); - free_page((unsigned long)kvm_svm->avic_physical_id_table); + free_pages((unsigned long)kvm_svm->avic_physical_id_table, + avic_get_physical_id_table_order(kvm)); spin_lock_irqsave(&svm_vm_data_hash_lock, flags); hash_del(&kvm_svm->hnode); @@ -274,10 +325,6 @@ int avic_vm_init(struct kvm *kvm) if (!enable_apicv) return 0; - kvm_svm->avic_physical_id_table = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT); - if (!kvm_svm->avic_physical_id_table) - goto free_avic; - kvm_svm->avic_logical_id_table = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT); if (!kvm_svm->avic_logical_id_table) goto free_avic; @@ -342,7 +389,7 @@ static int avic_init_backing_page(struct kvm_vcpu *vcpu) * fully initialized AVIC. */ if ((!x2avic_enabled && id > AVIC_MAX_PHYSICAL_ID) || - (id > X2AVIC_MAX_PHYSICAL_ID)) { + (id > x2avic_max_physical_id)) { kvm_set_apicv_inhibit(vcpu->kvm, APICV_INHIBIT_REASON_PHYSICAL_ID_TOO_BIG); vcpu->arch.apic->apicv_active = false; return 0; @@ -562,7 +609,7 @@ int avic_incomplete_ipi_interception(struct kvm_vcpu *vcpu) u32 icrh = svm->vmcb->control.exit_info_1 >> 32; u32 icrl = svm->vmcb->control.exit_info_1; u32 id = svm->vmcb->control.exit_info_2 >> 32; - u32 index = svm->vmcb->control.exit_info_2 & 0x1FF; + u32 index = svm->vmcb->control.exit_info_2 & AVIC_PHYSICAL_MAX_INDEX_MASK; struct kvm_lapic *apic = vcpu->arch.apic; trace_kvm_avic_incomplete_ipi(vcpu->vcpu_id, icrh, icrl, id, index); @@ -962,7 +1009,8 @@ static void __avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu, if (WARN_ON(h_physical_id & ~AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK)) return; - if (WARN_ON_ONCE(vcpu->vcpu_id * sizeof(entry) >= PAGE_SIZE)) + if (WARN_ON_ONCE(vcpu->vcpu_id * sizeof(entry) >= + PAGE_SIZE << avic_get_physical_id_table_order(vcpu->kvm))) return; /* @@ -1024,7 +1072,8 @@ static void __avic_vcpu_put(struct kvm_vcpu *vcpu, enum avic_vcpu_action action) lockdep_assert_preemption_disabled(); - if (WARN_ON_ONCE(vcpu->vcpu_id * sizeof(entry) >= PAGE_SIZE)) + if (WARN_ON_ONCE(vcpu->vcpu_id * sizeof(entry) >= + PAGE_SIZE << avic_get_physical_id_table_order(vcpu->kvm))) return; /* @@ -1226,10 +1275,15 @@ bool __init avic_hardware_setup(void) /* AVIC is a prerequisite for x2AVIC. */ x2avic_enabled = boot_cpu_has(X86_FEATURE_X2AVIC); - if (x2avic_enabled) - pr_info("x2AVIC enabled\n"); - else + if (x2avic_enabled) { + if (cpu_feature_enabled(X86_FEATURE_X2AVIC_EXT)) + x2avic_max_physical_id = X2AVIC_4K_MAX_PHYSICAL_ID; + else + x2avic_max_physical_id = X2AVIC_MAX_PHYSICAL_ID; + pr_info("x2AVIC enabled (max %u vCPUs)\n", x2avic_max_physical_id + 1); + } else { svm_x86_ops.allow_apicv_in_x2apic_without_x2apic_virtualization = true; + } /* * Disable IPI virtualization for AMD Family 17h CPUs (Zen1 and Zen2) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index da6e80b3ac35..c81005b24522 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -613,6 +613,7 @@ static void nested_vmcb02_prepare_save(struct vcpu_svm *svm, struct vmcb *vmcb12 struct kvm_vcpu *vcpu = &svm->vcpu; nested_vmcb02_compute_g_pat(svm); + vmcb_mark_dirty(vmcb02, VMCB_NPT); /* Load the nested guest state */ if (svm->nested.vmcb12_gpa != svm->nested.last_vmcb12_gpa) { @@ -751,6 +752,7 @@ static void nested_vmcb02_prepare_control(struct vcpu_svm *svm, vmcb02->control.nested_ctl = vmcb01->control.nested_ctl; vmcb02->control.iopm_base_pa = vmcb01->control.iopm_base_pa; vmcb02->control.msrpm_base_pa = vmcb01->control.msrpm_base_pa; + vmcb_mark_dirty(vmcb02, VMCB_PERM_MAP); /* * Stash vmcb02's counter if the guest hasn't moved past the guilty @@ -1430,16 +1432,6 @@ static int nested_svm_intercept(struct vcpu_svm *svm) case SVM_EXIT_IOIO: vmexit = nested_svm_intercept_ioio(svm); break; - case SVM_EXIT_READ_CR0 ... SVM_EXIT_WRITE_CR8: { - if (vmcb12_is_intercept(&svm->nested.ctl, exit_code)) - vmexit = NESTED_EXIT_DONE; - break; - } - case SVM_EXIT_READ_DR0 ... SVM_EXIT_WRITE_DR7: { - if (vmcb12_is_intercept(&svm->nested.ctl, exit_code)) - vmexit = NESTED_EXIT_DONE; - break; - } case SVM_EXIT_EXCP_BASE ... SVM_EXIT_EXCP_BASE + 0x1f: { /* * Host-intercepted exceptions have been checked already in diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 0835c664fbfd..f59c65abe3cf 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -65,20 +65,24 @@ module_param_named(ciphertext_hiding_asids, nr_ciphertext_hiding_asids, uint, 04 #define AP_RESET_HOLD_NAE_EVENT 1 #define AP_RESET_HOLD_MSR_PROTO 2 -/* As defined by SEV-SNP Firmware ABI, under "Guest Policy". */ -#define SNP_POLICY_MASK_API_MINOR GENMASK_ULL(7, 0) -#define SNP_POLICY_MASK_API_MAJOR GENMASK_ULL(15, 8) -#define SNP_POLICY_MASK_SMT BIT_ULL(16) -#define SNP_POLICY_MASK_RSVD_MBO BIT_ULL(17) -#define SNP_POLICY_MASK_DEBUG BIT_ULL(19) -#define SNP_POLICY_MASK_SINGLE_SOCKET BIT_ULL(20) - -#define SNP_POLICY_MASK_VALID (SNP_POLICY_MASK_API_MINOR | \ - SNP_POLICY_MASK_API_MAJOR | \ - SNP_POLICY_MASK_SMT | \ - SNP_POLICY_MASK_RSVD_MBO | \ - SNP_POLICY_MASK_DEBUG | \ - SNP_POLICY_MASK_SINGLE_SOCKET) +/* + * SEV-SNP policy bits that can be supported by KVM. These include policy bits + * that have implementation support within KVM or policy bits that do not + * require implementation support within KVM to enforce the policy. + */ +#define KVM_SNP_POLICY_MASK_VALID (SNP_POLICY_MASK_API_MINOR | \ + SNP_POLICY_MASK_API_MAJOR | \ + SNP_POLICY_MASK_SMT | \ + SNP_POLICY_MASK_RSVD_MBO | \ + SNP_POLICY_MASK_DEBUG | \ + SNP_POLICY_MASK_SINGLE_SOCKET | \ + SNP_POLICY_MASK_CXL_ALLOW | \ + SNP_POLICY_MASK_MEM_AES_256_XTS | \ + SNP_POLICY_MASK_RAPL_DIS | \ + SNP_POLICY_MASK_CIPHERTEXT_HIDING_DRAM | \ + SNP_POLICY_MASK_PAGE_SWAP_DISABLE) + +static u64 snp_supported_policy_bits __ro_after_init; #define INITIAL_VMSA_GPA 0xFFFFFFFFF000 @@ -2143,6 +2147,10 @@ int sev_dev_get_attr(u32 group, u64 attr, u64 *val) *val = sev_supported_vmsa_features; return 0; + case KVM_X86_SNP_POLICY_BITS: + *val = snp_supported_policy_bits; + return 0; + default: return -ENXIO; } @@ -2207,7 +2215,7 @@ static int snp_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp) if (params.flags) return -EINVAL; - if (params.policy & ~SNP_POLICY_MASK_VALID) + if (params.policy & ~snp_supported_policy_bits) return -EINVAL; /* Check for policy bits that must be set */ @@ -3100,8 +3108,11 @@ out: else if (sev_snp_supported) sev_snp_supported = is_sev_snp_initialized(); - if (sev_snp_supported) + if (sev_snp_supported) { + snp_supported_policy_bits = sev_get_snp_policy_bits() & + KVM_SNP_POLICY_MASK_VALID; nr_ciphertext_hiding_asids = init_args.max_snp_asid; + } /* * If ciphertext hiding is enabled, the joint SEV-ES/SEV-SNP @@ -5085,10 +5096,10 @@ struct vmcb_save_area *sev_decrypt_vmsa(struct kvm_vcpu *vcpu) /* Check if the SEV policy allows debugging */ if (sev_snp_guest(vcpu->kvm)) { - if (!(sev->policy & SNP_POLICY_DEBUG)) + if (!(sev->policy & SNP_POLICY_MASK_DEBUG)) return NULL; } else { - if (sev->policy & SEV_POLICY_NODBG) + if (sev->policy & SEV_POLICY_MASK_NODBG) return NULL; } diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 9d29b2e7e855..f56c2d895011 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -272,6 +272,7 @@ static void svm_set_interrupt_shadow(struct kvm_vcpu *vcpu, int mask) } static int __svm_skip_emulated_instruction(struct kvm_vcpu *vcpu, + int emul_type, bool commit_side_effects) { struct vcpu_svm *svm = to_svm(vcpu); @@ -293,7 +294,7 @@ static int __svm_skip_emulated_instruction(struct kvm_vcpu *vcpu, if (unlikely(!commit_side_effects)) old_rflags = svm->vmcb->save.rflags; - if (!kvm_emulate_instruction(vcpu, EMULTYPE_SKIP)) + if (!kvm_emulate_instruction(vcpu, emul_type)) return 0; if (unlikely(!commit_side_effects)) @@ -311,11 +312,13 @@ done: static int svm_skip_emulated_instruction(struct kvm_vcpu *vcpu) { - return __svm_skip_emulated_instruction(vcpu, true); + return __svm_skip_emulated_instruction(vcpu, EMULTYPE_SKIP, true); } -static int svm_update_soft_interrupt_rip(struct kvm_vcpu *vcpu) +static int svm_update_soft_interrupt_rip(struct kvm_vcpu *vcpu, u8 vector) { + const int emul_type = EMULTYPE_SKIP | EMULTYPE_SKIP_SOFT_INT | + EMULTYPE_SET_SOFT_INT_VECTOR(vector); unsigned long rip, old_rip = kvm_rip_read(vcpu); struct vcpu_svm *svm = to_svm(vcpu); @@ -331,7 +334,7 @@ static int svm_update_soft_interrupt_rip(struct kvm_vcpu *vcpu) * in use, the skip must not commit any side effects such as clearing * the interrupt shadow or RFLAGS.RF. */ - if (!__svm_skip_emulated_instruction(vcpu, !nrips)) + if (!__svm_skip_emulated_instruction(vcpu, emul_type, !nrips)) return -EIO; rip = kvm_rip_read(vcpu); @@ -367,7 +370,7 @@ static void svm_inject_exception(struct kvm_vcpu *vcpu) kvm_deliver_exception_payload(vcpu, ex); if (kvm_exception_is_soft(ex->vector) && - svm_update_soft_interrupt_rip(vcpu)) + svm_update_soft_interrupt_rip(vcpu, ex->vector)) return; svm->vmcb->control.event_inj = ex->vector @@ -1198,6 +1201,11 @@ void svm_switch_vmcb(struct vcpu_svm *svm, struct kvm_vmcb_info *target_vmcb) svm->vmcb = target_vmcb->ptr; } +static int svm_vcpu_precreate(struct kvm *kvm) +{ + return avic_alloc_physical_id_table(kvm); +} + static int svm_vcpu_create(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm; @@ -3442,13 +3450,8 @@ static bool svm_check_exit_valid(u64 exit_code) static int svm_handle_invalid_exit(struct kvm_vcpu *vcpu, u64 exit_code) { - vcpu_unimpl(vcpu, "svm: unexpected exit reason 0x%llx\n", exit_code); dump_vmcb(vcpu); - vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; - vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON; - vcpu->run->internal.ndata = 2; - vcpu->run->internal.data[0] = exit_code; - vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu; + kvm_prepare_unexpected_reason_exit(vcpu, exit_code); return 0; } @@ -3633,11 +3636,12 @@ static bool svm_set_vnmi_pending(struct kvm_vcpu *vcpu) static void svm_inject_irq(struct kvm_vcpu *vcpu, bool reinjected) { + struct kvm_queued_interrupt *intr = &vcpu->arch.interrupt; struct vcpu_svm *svm = to_svm(vcpu); u32 type; - if (vcpu->arch.interrupt.soft) { - if (svm_update_soft_interrupt_rip(vcpu)) + if (intr->soft) { + if (svm_update_soft_interrupt_rip(vcpu, intr->nr)) return; type = SVM_EVTINJ_TYPE_SOFT; @@ -3645,12 +3649,10 @@ static void svm_inject_irq(struct kvm_vcpu *vcpu, bool reinjected) type = SVM_EVTINJ_TYPE_INTR; } - trace_kvm_inj_virq(vcpu->arch.interrupt.nr, - vcpu->arch.interrupt.soft, reinjected); + trace_kvm_inj_virq(intr->nr, intr->soft, reinjected); ++vcpu->stat.irq_injections; - svm->vmcb->control.event_inj = vcpu->arch.interrupt.nr | - SVM_EVTINJ_VALID | type; + svm->vmcb->control.event_inj = intr->nr | SVM_EVTINJ_VALID | type; } void svm_complete_interrupt_delivery(struct kvm_vcpu *vcpu, int delivery_mode, @@ -4251,7 +4253,6 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags) svm_set_dr6(vcpu, DR6_ACTIVE_LOW); clgi(); - kvm_load_guest_xsave_state(vcpu); /* * Hardware only context switches DEBUGCTL if LBR virtualization is @@ -4294,7 +4295,6 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags) vcpu->arch.host_debugctl != svm->vmcb->save.dbgctl) update_debugctlmsr(vcpu->arch.host_debugctl); - kvm_load_host_xsave_state(vcpu); stgi(); /* Any pending NMI will happen here */ @@ -4326,14 +4326,6 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags) vcpu->arch.regs_avail &= ~SVM_REGS_LAZY_LOAD_SET; - /* - * We need to handle MC intercepts here before the vcpu has a chance to - * change the physical cpu - */ - if (unlikely(svm->vmcb->control.exit_code == - SVM_EXIT_EXCP_BASE + MC_VECTOR)) - svm_handle_mce(vcpu); - trace_kvm_exit(vcpu, KVM_ISA_SVM); svm_complete_interrupts(vcpu); @@ -4526,31 +4518,45 @@ static int svm_check_intercept(struct kvm_vcpu *vcpu, case SVM_EXIT_WRITE_CR0: { unsigned long cr0, val; - if (info->intercept == x86_intercept_cr_write) + /* + * Adjust the exit code accordingly if a CR other than CR0 is + * being written, and skip straight to the common handling as + * only CR0 has an additional selective intercept. + */ + if (info->intercept == x86_intercept_cr_write && info->modrm_reg) { icpt_info.exit_code += info->modrm_reg; - - if (icpt_info.exit_code != SVM_EXIT_WRITE_CR0 || - info->intercept == x86_intercept_clts) break; + } - if (!(vmcb12_is_intercept(&svm->nested.ctl, - INTERCEPT_SELECTIVE_CR0))) + /* + * Convert the exit_code to SVM_EXIT_CR0_SEL_WRITE if a + * selective CR0 intercept is triggered (the common logic will + * treat the selective intercept as being enabled). Note, the + * unconditional intercept has higher priority, i.e. this is + * only relevant if *only* the selective intercept is enabled. + */ + if (vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_CR0_WRITE) || + !(vmcb12_is_intercept(&svm->nested.ctl, INTERCEPT_SELECTIVE_CR0))) break; - cr0 = vcpu->arch.cr0 & ~SVM_CR0_SELECTIVE_MASK; - val = info->src_val & ~SVM_CR0_SELECTIVE_MASK; + /* CLTS never triggers INTERCEPT_SELECTIVE_CR0 */ + if (info->intercept == x86_intercept_clts) + break; + /* LMSW always triggers INTERCEPT_SELECTIVE_CR0 */ if (info->intercept == x86_intercept_lmsw) { - cr0 &= 0xfUL; - val &= 0xfUL; - /* lmsw can't clear PE - catch this here */ - if (cr0 & X86_CR0_PE) - val |= X86_CR0_PE; + icpt_info.exit_code = SVM_EXIT_CR0_SEL_WRITE; + break; } + /* + * MOV-to-CR0 only triggers INTERCEPT_SELECTIVE_CR0 if any bit + * other than SVM_CR0_SELECTIVE_MASK is changed. + */ + cr0 = vcpu->arch.cr0 & ~SVM_CR0_SELECTIVE_MASK; + val = info->src_val & ~SVM_CR0_SELECTIVE_MASK; if (cr0 ^ val) icpt_info.exit_code = SVM_EXIT_CR0_SEL_WRITE; - break; } case SVM_EXIT_READ_DR0: @@ -4622,8 +4628,16 @@ out: static void svm_handle_exit_irqoff(struct kvm_vcpu *vcpu) { - if (to_svm(vcpu)->vmcb->control.exit_code == SVM_EXIT_INTR) + switch (to_svm(vcpu)->vmcb->control.exit_code) { + case SVM_EXIT_EXCP_BASE + MC_VECTOR: + svm_handle_mce(vcpu); + break; + case SVM_EXIT_INTR: vcpu->arch.at_instruction_boundary = true; + break; + default: + break; + } } static void svm_setup_mce(struct kvm_vcpu *vcpu) @@ -5012,6 +5026,7 @@ struct kvm_x86_ops svm_x86_ops __initdata = { .emergency_disable_virtualization_cpu = svm_emergency_disable_virtualization_cpu, .has_emulated_msr = svm_has_emulated_msr, + .vcpu_precreate = svm_vcpu_precreate, .vcpu_create = svm_vcpu_create, .vcpu_free = svm_vcpu_free, .vcpu_reset = svm_vcpu_reset, @@ -5316,7 +5331,9 @@ static __init int svm_hardware_setup(void) if (nested) { pr_info("Nested Virtualization enabled\n"); - kvm_enable_efer_bits(EFER_SVME | EFER_LMSLE); + kvm_enable_efer_bits(EFER_SVME); + if (!boot_cpu_has(X86_FEATURE_EFER_LMSLE_MBZ)) + kvm_enable_efer_bits(EFER_LMSLE); r = nested_svm_init_msrpm_merge_offsets(); if (r) diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index dd78e6402345..9e151dbdef25 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -117,9 +117,6 @@ struct kvm_sev_info { cpumask_var_t have_run_cpus; /* CPUs that have done VMRUN for this VM. */ }; -#define SEV_POLICY_NODBG BIT_ULL(0) -#define SNP_POLICY_DEBUG BIT_ULL(19) - struct kvm_svm { struct kvm kvm; @@ -807,6 +804,7 @@ extern struct kvm_x86_nested_ops svm_nested_ops; bool __init avic_hardware_setup(void); void avic_hardware_unsetup(void); +int avic_alloc_physical_id_table(struct kvm *kvm); void avic_vm_destroy(struct kvm *kvm); int avic_vm_init(struct kvm *kvm); void avic_init_vmcb(struct vcpu_svm *svm, struct vmcb *vmcb); diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S index 235c4af6b692..3392bcadfb89 100644 --- a/arch/x86/kvm/svm/vmenter.S +++ b/arch/x86/kvm/svm/vmenter.S @@ -52,11 +52,23 @@ * there must not be any returns or indirect branches between this code * and vmentry. */ - movl SVM_spec_ctrl(%_ASM_DI), %eax - cmp PER_CPU_VAR(x86_spec_ctrl_current), %eax +#ifdef CONFIG_X86_64 + mov SVM_spec_ctrl(%rdi), %rdx + cmp PER_CPU_VAR(x86_spec_ctrl_current), %rdx + je 801b + movl %edx, %eax + shr $32, %rdx +#else + mov SVM_spec_ctrl(%edi), %eax + mov PER_CPU_VAR(x86_spec_ctrl_current), %ecx + xor %eax, %ecx + mov SVM_spec_ctrl + 4(%edi), %edx + mov PER_CPU_VAR(x86_spec_ctrl_current + 4), %esi + xor %edx, %esi + or %esi, %ecx je 801b +#endif mov $MSR_IA32_SPEC_CTRL, %ecx - xor %edx, %edx wrmsr jmp 801b .endm @@ -81,17 +93,31 @@ jnz 998f rdmsr movl %eax, SVM_spec_ctrl(%_ASM_DI) + movl %edx, SVM_spec_ctrl + 4(%_ASM_DI) 998: - /* Now restore the host value of the MSR if different from the guest's. */ - movl PER_CPU_VAR(x86_spec_ctrl_current), %eax - cmp SVM_spec_ctrl(%_ASM_DI), %eax +#ifdef CONFIG_X86_64 + mov PER_CPU_VAR(x86_spec_ctrl_current), %rdx + cmp SVM_spec_ctrl(%rdi), %rdx je 901b - xor %edx, %edx + movl %edx, %eax + shr $32, %rdx +#else + mov PER_CPU_VAR(x86_spec_ctrl_current), %eax + mov SVM_spec_ctrl(%edi), %esi + xor %eax, %esi + mov PER_CPU_VAR(x86_spec_ctrl_current + 4), %edx + mov SVM_spec_ctrl + 4(%edi), %edi + xor %edx, %edi + or %edi, %esi + je 901b +#endif wrmsr jmp 901b .endm +#define SVM_CLEAR_CPU_BUFFERS \ + ALTERNATIVE "", __CLEAR_CPU_BUFFERS, X86_FEATURE_CLEAR_CPU_BUF_VM /** * __svm_vcpu_run - Run a vCPU via a transition to SVM guest mode @@ -134,7 +160,7 @@ SYM_FUNC_START(__svm_vcpu_run) mov %_ASM_ARG1, %_ASM_DI .endif - /* Clobbers RAX, RCX, RDX. */ + /* Clobbers RAX, RCX, RDX (and ESI on 32-bit), consumes RDI (@svm). */ RESTORE_GUEST_SPEC_CTRL /* @@ -170,7 +196,7 @@ SYM_FUNC_START(__svm_vcpu_run) mov VCPU_RDI(%_ASM_DI), %_ASM_DI /* Clobbers EFLAGS.ZF */ - VM_CLEAR_CPU_BUFFERS + SVM_CLEAR_CPU_BUFFERS /* Enter guest mode */ 3: vmrun %_ASM_AX @@ -211,7 +237,10 @@ SYM_FUNC_START(__svm_vcpu_run) /* IMPORTANT: Stuff the RSB immediately after VM-Exit, before RET! */ FILL_RETURN_BUFFER %_ASM_AX, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_VMEXIT - /* Clobbers RAX, RCX, RDX. */ + /* + * Clobbers RAX, RCX, RDX (and ESI, EDI on 32-bit), consumes RDI (@svm) + * and RSP (pointer to @spec_ctrl_intercepted). + */ RESTORE_HOST_SPEC_CTRL /* @@ -331,7 +360,7 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run) mov %rdi, SEV_ES_RDI (%rdx) mov %rsi, SEV_ES_RSI (%rdx) - /* Clobbers RAX, RCX, RDX (@hostsa). */ + /* Clobbers RAX, RCX, and RDX (@hostsa), consumes RDI (@svm). */ RESTORE_GUEST_SPEC_CTRL /* Get svm->current_vmcb->pa into RAX. */ @@ -339,7 +368,7 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run) mov KVM_VMCB_pa(%rax), %rax /* Clobbers EFLAGS.ZF */ - VM_CLEAR_CPU_BUFFERS + SVM_CLEAR_CPU_BUFFERS /* Enter guest mode */ 1: vmrun %rax diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c index 0eb2773b2ae2..a46ccd670785 100644 --- a/arch/x86/kvm/vmx/main.c +++ b/arch/x86/kvm/vmx/main.c @@ -831,6 +831,14 @@ static int vt_vcpu_mem_enc_ioctl(struct kvm_vcpu *vcpu, void __user *argp) return tdx_vcpu_ioctl(vcpu, argp); } +static int vt_vcpu_mem_enc_unlocked_ioctl(struct kvm_vcpu *vcpu, void __user *argp) +{ + if (!is_td_vcpu(vcpu)) + return -EINVAL; + + return tdx_vcpu_unlocked_ioctl(vcpu, argp); +} + static int vt_gmem_max_mapping_level(struct kvm *kvm, kvm_pfn_t pfn, bool is_private) { @@ -1005,6 +1013,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = { .mem_enc_ioctl = vt_op_tdx_only(mem_enc_ioctl), .vcpu_mem_enc_ioctl = vt_op_tdx_only(vcpu_mem_enc_ioctl), + .vcpu_mem_enc_unlocked_ioctl = vt_op_tdx_only(vcpu_mem_enc_unlocked_ioctl), .gmem_max_mapping_level = vt_op_tdx_only(gmem_max_mapping_level) }; diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index bcea087b642f..40777278eabb 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -23,8 +23,8 @@ static bool __read_mostly enable_shadow_vmcs = 1; module_param_named(enable_shadow_vmcs, enable_shadow_vmcs, bool, S_IRUGO); -static bool __read_mostly nested_early_check = 0; -module_param(nested_early_check, bool, S_IRUGO); +static bool __ro_after_init warn_on_missed_cc; +module_param(warn_on_missed_cc, bool, 0444); #define CC KVM_NESTED_VMENTER_CONSISTENCY_CHECK @@ -555,6 +555,9 @@ static int nested_vmx_check_tpr_shadow_controls(struct kvm_vcpu *vcpu, if (CC(!page_address_valid(vcpu, vmcs12->virtual_apic_page_addr))) return -EINVAL; + if (CC(!nested_cpu_has_vid(vmcs12) && vmcs12->tpr_threshold >> 4)) + return -EINVAL; + return 0; } @@ -761,7 +764,7 @@ static void nested_cache_shadow_vmcs12(struct kvm_vcpu *vcpu, vmcs12->vmcs_link_pointer, VMCS12_SIZE)) return; - kvm_read_guest_cached(vmx->vcpu.kvm, ghc, get_shadow_vmcs12(vcpu), + kvm_read_guest_cached(vcpu->kvm, ghc, get_shadow_vmcs12(vcpu), VMCS12_SIZE); } @@ -780,7 +783,7 @@ static void nested_flush_cached_shadow_vmcs12(struct kvm_vcpu *vcpu, vmcs12->vmcs_link_pointer, VMCS12_SIZE)) return; - kvm_write_guest_cached(vmx->vcpu.kvm, ghc, get_shadow_vmcs12(vcpu), + kvm_write_guest_cached(vcpu->kvm, ghc, get_shadow_vmcs12(vcpu), VMCS12_SIZE); } @@ -2296,15 +2299,6 @@ static void prepare_vmcs02_constant_state(struct vcpu_vmx *vmx) return; vmx->nested.vmcs02_initialized = true; - /* - * We don't care what the EPTP value is we just need to guarantee - * it's valid so we don't get a false positive when doing early - * consistency checks. - */ - if (enable_ept && nested_early_check) - vmcs_write64(EPT_POINTER, - construct_eptp(&vmx->vcpu, 0, PT64_ROOT_4LEVEL)); - if (vmx->ve_info) vmcs_write64(VE_INFORMATION_ADDRESS, __pa(vmx->ve_info)); @@ -2749,7 +2743,7 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, vmcs_write64(GUEST_IA32_PAT, vmcs12->guest_ia32_pat); vcpu->arch.pat = vmcs12->guest_ia32_pat; } else if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT) { - vmcs_write64(GUEST_IA32_PAT, vmx->vcpu.arch.pat); + vmcs_write64(GUEST_IA32_PAT, vcpu->arch.pat); } vcpu->arch.tsc_offset = kvm_calc_nested_tsc_offset( @@ -2961,6 +2955,10 @@ static int nested_check_vm_execution_controls(struct kvm_vcpu *vcpu, } } + if (nested_cpu_has2(vmcs12, SECONDARY_EXEC_TSC_SCALING) && + CC(!vmcs12->tsc_multiplier)) + return -EINVAL; + return 0; } @@ -3078,6 +3076,38 @@ static int nested_vmx_check_controls(struct kvm_vcpu *vcpu, return 0; } +static int nested_vmx_check_controls_late(struct kvm_vcpu *vcpu, + struct vmcs12 *vmcs12) +{ + void *vapic = to_vmx(vcpu)->nested.virtual_apic_map.hva; + u32 vtpr = vapic ? (*(u32 *)(vapic + APIC_TASKPRI)) >> 4 : 0; + + /* + * Don't bother with the consistency checks if KVM isn't configured to + * WARN on missed consistency checks, as KVM needs to rely on hardware + * to fully detect an illegal vTPR vs. TRP Threshold combination due to + * the vTPR being writable by L1 at all times (it's an in-memory value, + * not a VMCS field). I.e. even if the check passes now, it might fail + * at the actual VM-Enter. + * + * Keying off the module param also allows treating an invalid vAPIC + * mapping as a consistency check failure without increasing the risk + * of breaking a "real" VM. + */ + if (!warn_on_missed_cc) + return 0; + + if ((exec_controls_get(to_vmx(vcpu)) & CPU_BASED_TPR_SHADOW) && + nested_cpu_has(vmcs12, CPU_BASED_TPR_SHADOW) && + !nested_cpu_has_vid(vmcs12) && + !nested_cpu_has2(vmcs12, SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES) && + (CC(!vapic) || + CC((vmcs12->tpr_threshold & GENMASK(3, 0)) > (vtpr & GENMASK(3, 0))))) + return -EINVAL; + + return 0; +} + static int nested_vmx_check_address_space_size(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) { @@ -3333,84 +3363,6 @@ static int nested_vmx_check_guest_state(struct kvm_vcpu *vcpu, return 0; } -static int nested_vmx_check_vmentry_hw(struct kvm_vcpu *vcpu) -{ - struct vcpu_vmx *vmx = to_vmx(vcpu); - unsigned long cr3, cr4; - bool vm_fail; - - if (!nested_early_check) - return 0; - - if (vmx->msr_autoload.host.nr) - vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, 0); - if (vmx->msr_autoload.guest.nr) - vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, 0); - - preempt_disable(); - - vmx_prepare_switch_to_guest(vcpu); - - /* - * Induce a consistency check VMExit by clearing bit 1 in GUEST_RFLAGS, - * which is reserved to '1' by hardware. GUEST_RFLAGS is guaranteed to - * be written (by prepare_vmcs02()) before the "real" VMEnter, i.e. - * there is no need to preserve other bits or save/restore the field. - */ - vmcs_writel(GUEST_RFLAGS, 0); - - cr3 = __get_current_cr3_fast(); - if (unlikely(cr3 != vmx->loaded_vmcs->host_state.cr3)) { - vmcs_writel(HOST_CR3, cr3); - vmx->loaded_vmcs->host_state.cr3 = cr3; - } - - cr4 = cr4_read_shadow(); - if (unlikely(cr4 != vmx->loaded_vmcs->host_state.cr4)) { - vmcs_writel(HOST_CR4, cr4); - vmx->loaded_vmcs->host_state.cr4 = cr4; - } - - vm_fail = __vmx_vcpu_run(vmx, (unsigned long *)&vcpu->arch.regs, - __vmx_vcpu_run_flags(vmx)); - - if (vmx->msr_autoload.host.nr) - vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.host.nr); - if (vmx->msr_autoload.guest.nr) - vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, vmx->msr_autoload.guest.nr); - - if (vm_fail) { - u32 error = vmcs_read32(VM_INSTRUCTION_ERROR); - - preempt_enable(); - - trace_kvm_nested_vmenter_failed( - "early hardware check VM-instruction error: ", error); - WARN_ON_ONCE(error != VMXERR_ENTRY_INVALID_CONTROL_FIELD); - return 1; - } - - /* - * VMExit clears RFLAGS.IF and DR7, even on a consistency check. - */ - if (hw_breakpoint_active()) - set_debugreg(__this_cpu_read(cpu_dr7), 7); - local_irq_enable(); - preempt_enable(); - - /* - * A non-failing VMEntry means we somehow entered guest mode with - * an illegal RIP, and that's just the tip of the iceberg. There - * is no telling what memory has been modified or what state has - * been exposed to unknown code. Hitting this all but guarantees - * a (very critical) hardware issue. - */ - WARN_ON(!(vmcs_read32(VM_EXIT_REASON) & - VMX_EXIT_REASONS_FAILED_VMENTRY)); - - return 0; -} - #ifdef CONFIG_KVM_HYPERV static bool nested_get_evmcs_page(struct kvm_vcpu *vcpu) { @@ -3667,22 +3619,18 @@ enum nvmx_vmentry_status nested_vmx_enter_non_root_mode(struct kvm_vcpu *vcpu, &vmx->nested.pre_vmenter_ssp_tbl); /* - * Overwrite vmcs01.GUEST_CR3 with L1's CR3 if EPT is disabled *and* - * nested early checks are disabled. In the event of a "late" VM-Fail, - * i.e. a VM-Fail detected by hardware but not KVM, KVM must unwind its - * software model to the pre-VMEntry host state. When EPT is disabled, - * GUEST_CR3 holds KVM's shadow CR3, not L1's "real" CR3, which causes - * nested_vmx_restore_host_state() to corrupt vcpu->arch.cr3. Stuffing - * vmcs01.GUEST_CR3 results in the unwind naturally setting arch.cr3 to - * the correct value. Smashing vmcs01.GUEST_CR3 is safe because nested - * VM-Exits, and the unwind, reset KVM's MMU, i.e. vmcs01.GUEST_CR3 is - * guaranteed to be overwritten with a shadow CR3 prior to re-entering - * L1. Don't stuff vmcs01.GUEST_CR3 when using nested early checks as - * KVM modifies vcpu->arch.cr3 if and only if the early hardware checks - * pass, and early VM-Fails do not reset KVM's MMU, i.e. the VM-Fail - * path would need to manually save/restore vmcs01.GUEST_CR3. + * Overwrite vmcs01.GUEST_CR3 with L1's CR3 if EPT is disabled. In the + * event of a "late" VM-Fail, i.e. a VM-Fail detected by hardware but + * not KVM, KVM must unwind its software model to the pre-VM-Entry host + * state. When EPT is disabled, GUEST_CR3 holds KVM's shadow CR3, not + * L1's "real" CR3, which causes nested_vmx_restore_host_state() to + * corrupt vcpu->arch.cr3. Stuffing vmcs01.GUEST_CR3 results in the + * unwind naturally setting arch.cr3 to the correct value. Smashing + * vmcs01.GUEST_CR3 is safe because nested VM-Exits, and the unwind, + * reset KVM's MMU, i.e. vmcs01.GUEST_CR3 is guaranteed to be + * overwritten with a shadow CR3 prior to re-entering L1. */ - if (!enable_ept && !nested_early_check) + if (!enable_ept) vmcs_writel(GUEST_CR3, vcpu->arch.cr3); vmx_switch_vmcs(vcpu, &vmx->nested.vmcs02); @@ -3695,7 +3643,7 @@ enum nvmx_vmentry_status nested_vmx_enter_non_root_mode(struct kvm_vcpu *vcpu, return NVMX_VMENTRY_KVM_INTERNAL_ERROR; } - if (nested_vmx_check_vmentry_hw(vcpu)) { + if (nested_vmx_check_controls_late(vcpu, vmcs12)) { vmx_switch_vmcs(vcpu, &vmx->vmcs01); return NVMX_VMENTRY_VMFAIL; } @@ -3880,7 +3828,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) goto vmentry_failed; /* Hide L1D cache contents from the nested guest. */ - vmx->vcpu.arch.l1tf_flush_l1d = true; + kvm_request_l1tf_flush_l1d(); /* * Must happen outside of nested_vmx_enter_non_root_mode() as it will @@ -5164,12 +5112,13 @@ void __nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 vm_exit_reason, /* * The only expected VM-instruction error is "VM entry with * invalid control field(s)." Anything else indicates a - * problem with L0. And we should never get here with a - * VMFail of any type if early consistency checks are enabled. + * problem with L0. */ WARN_ON_ONCE(vmcs_read32(VM_INSTRUCTION_ERROR) != VMXERR_ENTRY_INVALID_CONTROL_FIELD); - WARN_ON_ONCE(nested_early_check); + + /* VM-Fail at VM-Entry means KVM missed a consistency check. */ + WARN_ON_ONCE(warn_on_missed_cc); } /* diff --git a/arch/x86/kvm/vmx/run_flags.h b/arch/x86/kvm/vmx/run_flags.h index 2f20fb170def..6a87a12135fb 100644 --- a/arch/x86/kvm/vmx/run_flags.h +++ b/arch/x86/kvm/vmx/run_flags.h @@ -2,12 +2,8 @@ #ifndef __KVM_X86_VMX_RUN_FLAGS_H #define __KVM_X86_VMX_RUN_FLAGS_H -#define VMX_RUN_VMRESUME_SHIFT 0 -#define VMX_RUN_SAVE_SPEC_CTRL_SHIFT 1 -#define VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO_SHIFT 2 - -#define VMX_RUN_VMRESUME BIT(VMX_RUN_VMRESUME_SHIFT) -#define VMX_RUN_SAVE_SPEC_CTRL BIT(VMX_RUN_SAVE_SPEC_CTRL_SHIFT) -#define VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO BIT(VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO_SHIFT) +#define VMX_RUN_VMRESUME BIT(0) +#define VMX_RUN_SAVE_SPEC_CTRL BIT(1) +#define VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO BIT(2) #endif /* __KVM_X86_VMX_RUN_FLAGS_H */ diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 0a49c863c811..2d7a4d52ccfb 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -24,20 +24,33 @@ #undef pr_fmt #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt -#define pr_tdx_error(__fn, __err) \ - pr_err_ratelimited("SEAMCALL %s failed: 0x%llx\n", #__fn, __err) +#define __TDX_BUG_ON(__err, __f, __kvm, __fmt, __args...) \ +({ \ + struct kvm *_kvm = (__kvm); \ + bool __ret = !!(__err); \ + \ + if (WARN_ON_ONCE(__ret && (!_kvm || !_kvm->vm_bugged))) { \ + if (_kvm) \ + kvm_vm_bugged(_kvm); \ + pr_err_ratelimited("SEAMCALL " __f " failed: 0x%llx" __fmt "\n",\ + __err, __args); \ + } \ + unlikely(__ret); \ +}) + +#define TDX_BUG_ON(__err, __fn, __kvm) \ + __TDX_BUG_ON(__err, #__fn, __kvm, "%s", "") + +#define TDX_BUG_ON_1(__err, __fn, a1, __kvm) \ + __TDX_BUG_ON(__err, #__fn, __kvm, ", " #a1 " 0x%llx", a1) + +#define TDX_BUG_ON_2(__err, __fn, a1, a2, __kvm) \ + __TDX_BUG_ON(__err, #__fn, __kvm, ", " #a1 " 0x%llx, " #a2 " 0x%llx", a1, a2) + +#define TDX_BUG_ON_3(__err, __fn, a1, a2, a3, __kvm) \ + __TDX_BUG_ON(__err, #__fn, __kvm, ", " #a1 " 0x%llx, " #a2 ", 0x%llx, " #a3 " 0x%llx", \ + a1, a2, a3) -#define __pr_tdx_error_N(__fn_str, __err, __fmt, ...) \ - pr_err_ratelimited("SEAMCALL " __fn_str " failed: 0x%llx, " __fmt, __err, __VA_ARGS__) - -#define pr_tdx_error_1(__fn, __err, __rcx) \ - __pr_tdx_error_N(#__fn, __err, "rcx 0x%llx\n", __rcx) - -#define pr_tdx_error_2(__fn, __err, __rcx, __rdx) \ - __pr_tdx_error_N(#__fn, __err, "rcx 0x%llx, rdx 0x%llx\n", __rcx, __rdx) - -#define pr_tdx_error_3(__fn, __err, __rcx, __rdx, __r8) \ - __pr_tdx_error_N(#__fn, __err, "rcx 0x%llx, rdx 0x%llx, r8 0x%llx\n", __rcx, __rdx, __r8) bool enable_tdx __ro_after_init; module_param_named(tdx, enable_tdx, bool, 0444); @@ -281,25 +294,34 @@ static inline void tdx_disassociate_vp(struct kvm_vcpu *vcpu) vcpu->cpu = -1; } -static void tdx_no_vcpus_enter_start(struct kvm *kvm) -{ - struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); - - lockdep_assert_held_write(&kvm->mmu_lock); - - WRITE_ONCE(kvm_tdx->wait_for_sept_zap, true); - - kvm_make_all_cpus_request(kvm, KVM_REQ_OUTSIDE_GUEST_MODE); -} - -static void tdx_no_vcpus_enter_stop(struct kvm *kvm) -{ - struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); - - lockdep_assert_held_write(&kvm->mmu_lock); - - WRITE_ONCE(kvm_tdx->wait_for_sept_zap, false); -} +/* + * Execute a SEAMCALL related to removing/blocking S-EPT entries, with a single + * retry (if necessary) after forcing vCPUs to exit and wait for the operation + * to complete. All flows that remove/block S-EPT entries run with mmu_lock + * held for write, i.e. are mutually exclusive with each other, but they aren't + * mutually exclusive with running vCPUs, and so can fail with "operand busy" + * if a vCPU acquires a relevant lock in the TDX-Module, e.g. when doing TDCALL. + * + * Note, the retry is guaranteed to succeed, absent KVM and/or TDX-Module bugs. + */ +#define tdh_do_no_vcpus(tdh_func, kvm, args...) \ +({ \ + struct kvm_tdx *__kvm_tdx = to_kvm_tdx(kvm); \ + u64 __err; \ + \ + lockdep_assert_held_write(&kvm->mmu_lock); \ + \ + __err = tdh_func(args); \ + if (unlikely(tdx_operand_busy(__err))) { \ + WRITE_ONCE(__kvm_tdx->wait_for_sept_zap, true); \ + kvm_make_all_cpus_request(kvm, KVM_REQ_OUTSIDE_GUEST_MODE); \ + \ + __err = tdh_func(args); \ + \ + WRITE_ONCE(__kvm_tdx->wait_for_sept_zap, false); \ + } \ + __err; \ +}) /* TDH.PHYMEM.PAGE.RECLAIM is allowed only when destroying the TD. */ static int __tdx_reclaim_page(struct page *page) @@ -313,10 +335,9 @@ static int __tdx_reclaim_page(struct page *page) * before the HKID is released and control pages have also been * released at this point, so there is no possibility of contention. */ - if (WARN_ON_ONCE(err)) { - pr_tdx_error_3(TDH_PHYMEM_PAGE_RECLAIM, err, rcx, rdx, r8); + if (TDX_BUG_ON_3(err, TDH_PHYMEM_PAGE_RECLAIM, rcx, rdx, r8, NULL)) return -EIO; - } + return 0; } @@ -404,8 +425,8 @@ static void tdx_flush_vp_on_cpu(struct kvm_vcpu *vcpu) return; smp_call_function_single(cpu, tdx_flush_vp, &arg, 1); - if (KVM_BUG_ON(arg.err, vcpu->kvm)) - pr_tdx_error(TDH_VP_FLUSH, arg.err); + + TDX_BUG_ON(arg.err, TDH_VP_FLUSH, vcpu->kvm); } void tdx_disable_virtualization_cpu(void) @@ -464,8 +485,7 @@ static void smp_func_do_phymem_cache_wb(void *unused) } out: - if (WARN_ON_ONCE(err)) - pr_tdx_error(TDH_PHYMEM_CACHE_WB, err); + TDX_BUG_ON(err, TDH_PHYMEM_CACHE_WB, NULL); } void tdx_mmu_release_hkid(struct kvm *kvm) @@ -504,8 +524,7 @@ void tdx_mmu_release_hkid(struct kvm *kvm) err = tdh_mng_vpflushdone(&kvm_tdx->td); if (err == TDX_FLUSHVP_NOT_DONE) goto out; - if (KVM_BUG_ON(err, kvm)) { - pr_tdx_error(TDH_MNG_VPFLUSHDONE, err); + if (TDX_BUG_ON(err, TDH_MNG_VPFLUSHDONE, kvm)) { pr_err("tdh_mng_vpflushdone() failed. HKID %d is leaked.\n", kvm_tdx->hkid); goto out; @@ -528,8 +547,7 @@ void tdx_mmu_release_hkid(struct kvm *kvm) * tdh_mng_key_freeid() will fail. */ err = tdh_mng_key_freeid(&kvm_tdx->td); - if (KVM_BUG_ON(err, kvm)) { - pr_tdx_error(TDH_MNG_KEY_FREEID, err); + if (TDX_BUG_ON(err, TDH_MNG_KEY_FREEID, kvm)) { pr_err("tdh_mng_key_freeid() failed. HKID %d is leaked.\n", kvm_tdx->hkid); } else { @@ -580,10 +598,9 @@ static void tdx_reclaim_td_control_pages(struct kvm *kvm) * when it is reclaiming TDCS). */ err = tdh_phymem_page_wbinvd_tdr(&kvm_tdx->td); - if (KVM_BUG_ON(err, kvm)) { - pr_tdx_error(TDH_PHYMEM_PAGE_WBINVD, err); + if (TDX_BUG_ON(err, TDH_PHYMEM_PAGE_WBINVD, kvm)) return; - } + tdx_quirk_reset_page(kvm_tdx->td.tdr_page); __free_page(kvm_tdx->td.tdr_page); @@ -606,11 +623,8 @@ static int tdx_do_tdh_mng_key_config(void *param) /* TDX_RND_NO_ENTROPY related retries are handled by sc_retry() */ err = tdh_mng_key_config(&kvm_tdx->td); - - if (KVM_BUG_ON(err, &kvm_tdx->kvm)) { - pr_tdx_error(TDH_MNG_KEY_CONFIG, err); + if (TDX_BUG_ON(err, TDH_MNG_KEY_CONFIG, &kvm_tdx->kvm)) return -EIO; - } return 0; } @@ -763,25 +777,6 @@ static bool tdx_protected_apic_has_interrupt(struct kvm_vcpu *vcpu) return tdx_vcpu_state_details_intr_pending(vcpu_state_details); } -/* - * Compared to vmx_prepare_switch_to_guest(), there is not much to do - * as SEAMCALL/SEAMRET calls take care of most of save and restore. - */ -void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) -{ - struct vcpu_vt *vt = to_vt(vcpu); - - if (vt->guest_state_loaded) - return; - - if (likely(is_64bit_mm(current->mm))) - vt->msr_host_kernel_gs_base = current->thread.gsbase; - else - vt->msr_host_kernel_gs_base = read_msr(MSR_KERNEL_GS_BASE); - - vt->guest_state_loaded = true; -} - struct tdx_uret_msr { u32 msr; unsigned int slot; @@ -795,19 +790,38 @@ static struct tdx_uret_msr tdx_uret_msrs[] = { {.msr = MSR_TSC_AUX,}, }; -static void tdx_user_return_msr_update_cache(void) +void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) { + struct vcpu_vt *vt = to_vt(vcpu); int i; + if (vt->guest_state_loaded) + return; + + if (likely(is_64bit_mm(current->mm))) + vt->msr_host_kernel_gs_base = current->thread.gsbase; + else + vt->msr_host_kernel_gs_base = read_msr(MSR_KERNEL_GS_BASE); + + vt->guest_state_loaded = true; + + /* + * Explicitly set user-return MSRs that are clobbered by the TDX-Module + * if VP.ENTER succeeds, i.e. on TD-Exit, with the values that would be + * written by the TDX-Module. Don't rely on the TDX-Module to actually + * clobber the MSRs, as the contract is poorly defined and not upheld. + * E.g. the TDX-Module will synthesize an EPT Violation without doing + * VM-Enter if it suspects a zero-step attack, and never "restore" VMM + * state. + */ for (i = 0; i < ARRAY_SIZE(tdx_uret_msrs); i++) - kvm_user_return_msr_update_cache(tdx_uret_msrs[i].slot, - tdx_uret_msrs[i].defval); + kvm_set_user_return_msr(tdx_uret_msrs[i].slot, + tdx_uret_msrs[i].defval, -1ull); } static void tdx_prepare_switch_to_host(struct kvm_vcpu *vcpu) { struct vcpu_vt *vt = to_vt(vcpu); - struct vcpu_tdx *tdx = to_tdx(vcpu); if (!vt->guest_state_loaded) return; @@ -815,11 +829,6 @@ static void tdx_prepare_switch_to_host(struct kvm_vcpu *vcpu) ++vcpu->stat.host_state_reload; wrmsrl(MSR_KERNEL_GS_BASE, vt->msr_host_kernel_gs_base); - if (tdx->guest_entered) { - tdx_user_return_msr_update_cache(); - tdx->guest_entered = false; - } - vt->guest_state_loaded = false; } @@ -829,19 +838,52 @@ void tdx_vcpu_put(struct kvm_vcpu *vcpu) tdx_prepare_switch_to_host(vcpu); } +/* + * Life cycles for a TD and a vCPU: + * 1. KVM_CREATE_VM ioctl. + * TD state is TD_STATE_UNINITIALIZED. + * hkid is not assigned at this stage. + * 2. KVM_TDX_INIT_VM ioctl. + * TD transitions to TD_STATE_INITIALIZED. + * hkid is assigned after this stage. + * 3. KVM_CREATE_VCPU ioctl. (only when TD is TD_STATE_INITIALIZED). + * 3.1 tdx_vcpu_create() transitions vCPU state to VCPU_TD_STATE_UNINITIALIZED. + * 3.2 vcpu_load() and vcpu_put() in kvm_arch_vcpu_create(). + * 3.3 (conditional) if any error encountered after kvm_arch_vcpu_create() + * kvm_arch_vcpu_destroy() --> tdx_vcpu_free(). + * 4. KVM_TDX_INIT_VCPU ioctl. + * tdx_vcpu_init() transitions vCPU state to VCPU_TD_STATE_INITIALIZED. + * vCPU control structures are allocated at this stage. + * 5. kvm_destroy_vm(). + * 5.1 tdx_mmu_release_hkid(): (1) tdh_vp_flush(), disassociates all vCPUs. + * (2) puts hkid to !assigned state. + * 5.2 kvm_destroy_vcpus() --> tdx_vcpu_free(): + * transitions vCPU to VCPU_TD_STATE_UNINITIALIZED state. + * 5.3 tdx_vm_destroy() + * transitions TD to TD_STATE_UNINITIALIZED state. + * + * tdx_vcpu_free() can be invoked only at 3.3 or 5.2. + * - If at 3.3, hkid is still assigned, but the vCPU must be in + * VCPU_TD_STATE_UNINITIALIZED state. + * - if at 5.2, hkid must be !assigned and all vCPUs must be in + * VCPU_TD_STATE_INITIALIZED state and have been dissociated. + */ void tdx_vcpu_free(struct kvm_vcpu *vcpu) { struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm); struct vcpu_tdx *tdx = to_tdx(vcpu); int i; + if (vcpu->cpu != -1) { + KVM_BUG_ON(tdx->state == VCPU_TD_STATE_INITIALIZED, vcpu->kvm); + tdx_flush_vp_on_cpu(vcpu); + return; + } + /* * It is not possible to reclaim pages while hkid is assigned. It might - * be assigned if: - * 1. the TD VM is being destroyed but freeing hkid failed, in which - * case the pages are leaked - * 2. TD VCPU creation failed and this on the error path, in which case - * there is nothing to do anyway + * be assigned if the TD VM is being destroyed but freeing hkid failed, + * in which case the pages are leaked. */ if (is_hkid_assigned(kvm_tdx)) return; @@ -856,7 +898,7 @@ void tdx_vcpu_free(struct kvm_vcpu *vcpu) } if (tdx->vp.tdvpr_page) { tdx_reclaim_control_page(tdx->vp.tdvpr_page); - tdx->vp.tdvpr_page = 0; + tdx->vp.tdvpr_page = NULL; tdx->vp.tdvpr_pa = 0; } @@ -1059,7 +1101,6 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags) update_debugctlmsr(vcpu->arch.host_debugctl); tdx_load_host_xsave_state(vcpu); - tdx->guest_entered = true; vcpu->arch.regs_avail &= TDX_REGS_AVAIL_SET; @@ -1069,9 +1110,6 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags) if (unlikely((tdx->vp_enter_ret & TDX_SW_ERROR) == TDX_SW_ERROR)) return EXIT_FASTPATH_NONE; - if (unlikely(vmx_get_exit_reason(vcpu).basic == EXIT_REASON_MCE_DURING_VMENTRY)) - kvm_machine_check(); - trace_kvm_exit(vcpu, KVM_ISA_VMX); if (unlikely(tdx_failed_vmentry(vcpu))) @@ -1583,137 +1621,79 @@ void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int pgd_level) td_vmcs_write64(to_tdx(vcpu), SHARED_EPT_POINTER, root_hpa); } -static void tdx_unpin(struct kvm *kvm, struct page *page) +static int tdx_mem_page_add(struct kvm *kvm, gfn_t gfn, enum pg_level level, + kvm_pfn_t pfn) { - put_page(page); + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); + u64 err, entry, level_state; + gpa_t gpa = gfn_to_gpa(gfn); + + lockdep_assert_held(&kvm->slots_lock); + + if (KVM_BUG_ON(kvm->arch.pre_fault_allowed, kvm) || + KVM_BUG_ON(!kvm_tdx->page_add_src, kvm)) + return -EIO; + + err = tdh_mem_page_add(&kvm_tdx->td, gpa, pfn_to_page(pfn), + kvm_tdx->page_add_src, &entry, &level_state); + if (unlikely(tdx_operand_busy(err))) + return -EBUSY; + + if (TDX_BUG_ON_2(err, TDH_MEM_PAGE_ADD, entry, level_state, kvm)) + return -EIO; + + return 0; } static int tdx_mem_page_aug(struct kvm *kvm, gfn_t gfn, - enum pg_level level, struct page *page) + enum pg_level level, kvm_pfn_t pfn) { int tdx_level = pg_level_to_tdx_sept_level(level); struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); + struct page *page = pfn_to_page(pfn); gpa_t gpa = gfn_to_gpa(gfn); u64 entry, level_state; u64 err; err = tdh_mem_page_aug(&kvm_tdx->td, gpa, tdx_level, page, &entry, &level_state); - if (unlikely(tdx_operand_busy(err))) { - tdx_unpin(kvm, page); + if (unlikely(tdx_operand_busy(err))) return -EBUSY; - } - if (KVM_BUG_ON(err, kvm)) { - pr_tdx_error_2(TDH_MEM_PAGE_AUG, err, entry, level_state); - tdx_unpin(kvm, page); + if (TDX_BUG_ON_2(err, TDH_MEM_PAGE_AUG, entry, level_state, kvm)) return -EIO; - } - - return 0; -} - -/* - * KVM_TDX_INIT_MEM_REGION calls kvm_gmem_populate() to map guest pages; the - * callback tdx_gmem_post_populate() then maps pages into private memory. - * through the a seamcall TDH.MEM.PAGE.ADD(). The SEAMCALL also requires the - * private EPT structures for the page to have been built before, which is - * done via kvm_tdp_map_page(). nr_premapped counts the number of pages that - * were added to the EPT structures but not added with TDH.MEM.PAGE.ADD(). - * The counter has to be zero on KVM_TDX_FINALIZE_VM, to ensure that there - * are no half-initialized shared EPT pages. - */ -static int tdx_mem_page_record_premap_cnt(struct kvm *kvm, gfn_t gfn, - enum pg_level level, kvm_pfn_t pfn) -{ - struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); - - if (KVM_BUG_ON(kvm->arch.pre_fault_allowed, kvm)) - return -EINVAL; - /* nr_premapped will be decreased when tdh_mem_page_add() is called. */ - atomic64_inc(&kvm_tdx->nr_premapped); return 0; } static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn, - enum pg_level level, kvm_pfn_t pfn) + enum pg_level level, u64 mirror_spte) { struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); - struct page *page = pfn_to_page(pfn); + kvm_pfn_t pfn = spte_to_pfn(mirror_spte); /* TODO: handle large pages. */ if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm)) - return -EINVAL; + return -EIO; - /* - * Because guest_memfd doesn't support page migration with - * a_ops->migrate_folio (yet), no callback is triggered for KVM on page - * migration. Until guest_memfd supports page migration, prevent page - * migration. - * TODO: Once guest_memfd introduces callback on page migration, - * implement it and remove get_page/put_page(). - */ - get_page(page); + WARN_ON_ONCE(!is_shadow_present_pte(mirror_spte) || + (mirror_spte & VMX_EPT_RWX_MASK) != VMX_EPT_RWX_MASK); /* - * Read 'pre_fault_allowed' before 'kvm_tdx->state'; see matching - * barrier in tdx_td_finalize(). + * Ensure pre_fault_allowed is read by kvm_arch_vcpu_pre_fault_memory() + * before kvm_tdx->state. Userspace must not be allowed to pre-fault + * arbitrary memory until the initial memory image is finalized. Pairs + * with the smp_wmb() in tdx_td_finalize(). */ smp_rmb(); - if (likely(kvm_tdx->state == TD_STATE_RUNNABLE)) - return tdx_mem_page_aug(kvm, gfn, level, page); - - return tdx_mem_page_record_premap_cnt(kvm, gfn, level, pfn); -} - -static int tdx_sept_drop_private_spte(struct kvm *kvm, gfn_t gfn, - enum pg_level level, struct page *page) -{ - int tdx_level = pg_level_to_tdx_sept_level(level); - struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); - gpa_t gpa = gfn_to_gpa(gfn); - u64 err, entry, level_state; - - /* TODO: handle large pages. */ - if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm)) - return -EINVAL; - - if (KVM_BUG_ON(!is_hkid_assigned(kvm_tdx), kvm)) - return -EINVAL; /* - * When zapping private page, write lock is held. So no race condition - * with other vcpu sept operation. - * Race with TDH.VP.ENTER due to (0-step mitigation) and Guest TDCALLs. + * If the TD isn't finalized/runnable, then userspace is initializing + * the VM image via KVM_TDX_INIT_MEM_REGION; ADD the page to the TD. */ - err = tdh_mem_page_remove(&kvm_tdx->td, gpa, tdx_level, &entry, - &level_state); - - if (unlikely(tdx_operand_busy(err))) { - /* - * The second retry is expected to succeed after kicking off all - * other vCPUs and prevent them from invoking TDH.VP.ENTER. - */ - tdx_no_vcpus_enter_start(kvm); - err = tdh_mem_page_remove(&kvm_tdx->td, gpa, tdx_level, &entry, - &level_state); - tdx_no_vcpus_enter_stop(kvm); - } - - if (KVM_BUG_ON(err, kvm)) { - pr_tdx_error_2(TDH_MEM_PAGE_REMOVE, err, entry, level_state); - return -EIO; - } - - err = tdh_phymem_page_wbinvd_hkid((u16)kvm_tdx->hkid, page); + if (unlikely(kvm_tdx->state != TD_STATE_RUNNABLE)) + return tdx_mem_page_add(kvm, gfn, level, pfn); - if (KVM_BUG_ON(err, kvm)) { - pr_tdx_error(TDH_PHYMEM_PAGE_WBINVD, err); - return -EIO; - } - tdx_quirk_reset_page(page); - tdx_unpin(kvm, page); - return 0; + return tdx_mem_page_aug(kvm, gfn, level, pfn); } static int tdx_sept_link_private_spt(struct kvm *kvm, gfn_t gfn, @@ -1729,81 +1709,13 @@ static int tdx_sept_link_private_spt(struct kvm *kvm, gfn_t gfn, if (unlikely(tdx_operand_busy(err))) return -EBUSY; - if (KVM_BUG_ON(err, kvm)) { - pr_tdx_error_2(TDH_MEM_SEPT_ADD, err, entry, level_state); + if (TDX_BUG_ON_2(err, TDH_MEM_SEPT_ADD, entry, level_state, kvm)) return -EIO; - } return 0; } /* - * Check if the error returned from a SEPT zap SEAMCALL is due to that a page is - * mapped by KVM_TDX_INIT_MEM_REGION without tdh_mem_page_add() being called - * successfully. - * - * Since tdh_mem_sept_add() must have been invoked successfully before a - * non-leaf entry present in the mirrored page table, the SEPT ZAP related - * SEAMCALLs should not encounter err TDX_EPT_WALK_FAILED. They should instead - * find TDX_EPT_ENTRY_STATE_INCORRECT due to an empty leaf entry found in the - * SEPT. - * - * Further check if the returned entry from SEPT walking is with RWX permissions - * to filter out anything unexpected. - * - * Note: @level is pg_level, not the tdx_level. The tdx_level extracted from - * level_state returned from a SEAMCALL error is the same as that passed into - * the SEAMCALL. - */ -static int tdx_is_sept_zap_err_due_to_premap(struct kvm_tdx *kvm_tdx, u64 err, - u64 entry, int level) -{ - if (!err || kvm_tdx->state == TD_STATE_RUNNABLE) - return false; - - if (err != (TDX_EPT_ENTRY_STATE_INCORRECT | TDX_OPERAND_ID_RCX)) - return false; - - if ((is_last_spte(entry, level) && (entry & VMX_EPT_RWX_MASK))) - return false; - - return true; -} - -static int tdx_sept_zap_private_spte(struct kvm *kvm, gfn_t gfn, - enum pg_level level, struct page *page) -{ - int tdx_level = pg_level_to_tdx_sept_level(level); - struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); - gpa_t gpa = gfn_to_gpa(gfn) & KVM_HPAGE_MASK(level); - u64 err, entry, level_state; - - /* For now large page isn't supported yet. */ - WARN_ON_ONCE(level != PG_LEVEL_4K); - - err = tdh_mem_range_block(&kvm_tdx->td, gpa, tdx_level, &entry, &level_state); - - if (unlikely(tdx_operand_busy(err))) { - /* After no vCPUs enter, the second retry is expected to succeed */ - tdx_no_vcpus_enter_start(kvm); - err = tdh_mem_range_block(&kvm_tdx->td, gpa, tdx_level, &entry, &level_state); - tdx_no_vcpus_enter_stop(kvm); - } - if (tdx_is_sept_zap_err_due_to_premap(kvm_tdx, err, entry, level) && - !KVM_BUG_ON(!atomic64_read(&kvm_tdx->nr_premapped), kvm)) { - atomic64_dec(&kvm_tdx->nr_premapped); - tdx_unpin(kvm, page); - return 0; - } - - if (KVM_BUG_ON(err, kvm)) { - pr_tdx_error_2(TDH_MEM_RANGE_BLOCK, err, entry, level_state); - return -EIO; - } - return 1; -} - -/* * Ensure shared and private EPTs to be flushed on all vCPUs. * tdh_mem_track() is the only caller that increases TD epoch. An increase in * the TD epoch (e.g., to value "N + 1") is successful only if no vCPUs are @@ -1836,18 +1748,15 @@ static void tdx_track(struct kvm *kvm) if (unlikely(kvm_tdx->state != TD_STATE_RUNNABLE)) return; + /* + * The full sequence of TDH.MEM.TRACK and forcing vCPUs out of guest + * mode must be serialized, as TDH.MEM.TRACK will fail if the previous + * tracking epoch hasn't completed. + */ lockdep_assert_held_write(&kvm->mmu_lock); - err = tdh_mem_track(&kvm_tdx->td); - if (unlikely(tdx_operand_busy(err))) { - /* After no vCPUs enter, the second retry is expected to succeed */ - tdx_no_vcpus_enter_start(kvm); - err = tdh_mem_track(&kvm_tdx->td); - tdx_no_vcpus_enter_stop(kvm); - } - - if (KVM_BUG_ON(err, kvm)) - pr_tdx_error(TDH_MEM_TRACK, err); + err = tdh_do_no_vcpus(tdh_mem_track, kvm, &kvm_tdx->td); + TDX_BUG_ON(err, TDH_MEM_TRACK, kvm); kvm_make_all_cpus_request(kvm, KVM_REQ_OUTSIDE_GUEST_MODE); } @@ -1866,7 +1775,7 @@ static int tdx_sept_free_private_spt(struct kvm *kvm, gfn_t gfn, * and slot move/deletion. */ if (KVM_BUG_ON(is_hkid_assigned(kvm_tdx), kvm)) - return -EINVAL; + return -EIO; /* * The HKID assigned to this TD was already freed and cache was @@ -1875,11 +1784,16 @@ static int tdx_sept_free_private_spt(struct kvm *kvm, gfn_t gfn, return tdx_reclaim_page(virt_to_page(private_spt)); } -static int tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn, - enum pg_level level, kvm_pfn_t pfn) +static void tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn, + enum pg_level level, u64 mirror_spte) { - struct page *page = pfn_to_page(pfn); - int ret; + struct page *page = pfn_to_page(spte_to_pfn(mirror_spte)); + int tdx_level = pg_level_to_tdx_sept_level(level); + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); + gpa_t gpa = gfn_to_gpa(gfn); + u64 err, entry, level_state; + + lockdep_assert_held_write(&kvm->mmu_lock); /* * HKID is released after all private pages have been removed, and set @@ -1887,11 +1801,16 @@ static int tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn, * there can't be anything populated in the private EPT. */ if (KVM_BUG_ON(!is_hkid_assigned(to_kvm_tdx(kvm)), kvm)) - return -EINVAL; + return; - ret = tdx_sept_zap_private_spte(kvm, gfn, level, page); - if (ret <= 0) - return ret; + /* TODO: handle large pages. */ + if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm)) + return; + + err = tdh_do_no_vcpus(tdh_mem_range_block, kvm, &kvm_tdx->td, gpa, + tdx_level, &entry, &level_state); + if (TDX_BUG_ON_2(err, TDH_MEM_RANGE_BLOCK, entry, level_state, kvm)) + return; /* * TDX requires TLB tracking before dropping private page. Do @@ -1899,7 +1818,21 @@ static int tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn, */ tdx_track(kvm); - return tdx_sept_drop_private_spte(kvm, gfn, level, page); + /* + * When zapping private page, write lock is held. So no race condition + * with other vcpu sept operation. + * Race with TDH.VP.ENTER due to (0-step mitigation) and Guest TDCALLs. + */ + err = tdh_do_no_vcpus(tdh_mem_page_remove, kvm, &kvm_tdx->td, gpa, + tdx_level, &entry, &level_state); + if (TDX_BUG_ON_2(err, TDH_MEM_PAGE_REMOVE, entry, level_state, kvm)) + return; + + err = tdh_phymem_page_wbinvd_hkid((u16)kvm_tdx->hkid, page); + if (TDX_BUG_ON(err, TDH_PHYMEM_PAGE_WBINVD, kvm)) + return; + + tdx_quirk_reset_page(page); } void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode, @@ -2145,11 +2078,7 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t fastpath) } unhandled_exit: - vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; - vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON; - vcpu->run->internal.ndata = 2; - vcpu->run->internal.data[0] = vp_enter_ret; - vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu; + kvm_prepare_unexpected_reason_exit(vcpu, vp_enter_ret); return 0; } @@ -2282,37 +2211,28 @@ static int tdx_get_capabilities(struct kvm_tdx_cmd *cmd) if (cmd->flags) return -EINVAL; - caps = kzalloc(sizeof(*caps) + - sizeof(struct kvm_cpuid_entry2) * td_conf->num_cpuid_config, - GFP_KERNEL); - if (!caps) - return -ENOMEM; - user_caps = u64_to_user_ptr(cmd->data); - if (get_user(nr_user_entries, &user_caps->cpuid.nent)) { - ret = -EFAULT; - goto out; - } + if (get_user(nr_user_entries, &user_caps->cpuid.nent)) + return -EFAULT; - if (nr_user_entries < td_conf->num_cpuid_config) { - ret = -E2BIG; - goto out; - } + if (nr_user_entries < td_conf->num_cpuid_config) + return -E2BIG; + + caps = kzalloc(struct_size(caps, cpuid.entries, + td_conf->num_cpuid_config), GFP_KERNEL); + if (!caps) + return -ENOMEM; ret = init_kvm_tdx_caps(td_conf, caps); if (ret) goto out; - if (copy_to_user(user_caps, caps, sizeof(*caps))) { + if (copy_to_user(user_caps, caps, struct_size(caps, cpuid.entries, + caps->cpuid.nent))) { ret = -EFAULT; goto out; } - if (copy_to_user(user_caps->cpuid.entries, caps->cpuid.entries, - caps->cpuid.nent * - sizeof(caps->cpuid.entries[0]))) - ret = -EFAULT; - out: /* kfree() accepts NULL. */ kfree(caps); @@ -2537,8 +2457,7 @@ static int __tdx_td_init(struct kvm *kvm, struct td_params *td_params, goto free_packages; } - if (WARN_ON_ONCE(err)) { - pr_tdx_error(TDH_MNG_CREATE, err); + if (TDX_BUG_ON(err, TDH_MNG_CREATE, kvm)) { ret = -EIO; goto free_packages; } @@ -2579,8 +2498,7 @@ static int __tdx_td_init(struct kvm *kvm, struct td_params *td_params, ret = -EAGAIN; goto teardown; } - if (WARN_ON_ONCE(err)) { - pr_tdx_error(TDH_MNG_ADDCX, err); + if (TDX_BUG_ON(err, TDH_MNG_ADDCX, kvm)) { ret = -EIO; goto teardown; } @@ -2597,8 +2515,7 @@ static int __tdx_td_init(struct kvm *kvm, struct td_params *td_params, *seamcall_err = err; ret = -EINVAL; goto teardown; - } else if (WARN_ON_ONCE(err)) { - pr_tdx_error_1(TDH_MNG_INIT, err, rcx); + } else if (TDX_BUG_ON_1(err, TDH_MNG_INIT, rcx, kvm)) { ret = -EIO; goto teardown; } @@ -2642,7 +2559,7 @@ free_tdcs: free_tdr: if (tdr_page) __free_page(tdr_page); - kvm_tdx->td.tdr_page = 0; + kvm_tdx->td.tdr_page = NULL; free_hkid: tdx_hkid_free(kvm_tdx); @@ -2747,11 +2664,53 @@ err_out: return -EIO; } +typedef void *tdx_vm_state_guard_t; + +static tdx_vm_state_guard_t tdx_acquire_vm_state_locks(struct kvm *kvm) +{ + int r; + + mutex_lock(&kvm->lock); + + if (kvm->created_vcpus != atomic_read(&kvm->online_vcpus)) { + r = -EBUSY; + goto out_err; + } + + r = kvm_lock_all_vcpus(kvm); + if (r) + goto out_err; + + /* + * Note the unintuitive ordering! vcpu->mutex must be taken outside + * kvm->slots_lock! + */ + mutex_lock(&kvm->slots_lock); + return kvm; + +out_err: + mutex_unlock(&kvm->lock); + return ERR_PTR(r); +} + +static void tdx_release_vm_state_locks(struct kvm *kvm) +{ + mutex_unlock(&kvm->slots_lock); + kvm_unlock_all_vcpus(kvm); + mutex_unlock(&kvm->lock); +} + +DEFINE_CLASS(tdx_vm_state_guard, tdx_vm_state_guard_t, + if (!IS_ERR(_T)) tdx_release_vm_state_locks(_T), + tdx_acquire_vm_state_locks(kvm), struct kvm *kvm); + static int tdx_td_init(struct kvm *kvm, struct kvm_tdx_cmd *cmd) { + struct kvm_tdx_init_vm __user *user_data = u64_to_user_ptr(cmd->data); struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); struct kvm_tdx_init_vm *init_vm; struct td_params *td_params = NULL; + u32 nr_user_entries; int ret; BUILD_BUG_ON(sizeof(*init_vm) != 256 + sizeof_field(struct kvm_tdx_init_vm, cpuid)); @@ -2763,28 +2722,16 @@ static int tdx_td_init(struct kvm *kvm, struct kvm_tdx_cmd *cmd) if (cmd->flags) return -EINVAL; - init_vm = kmalloc(sizeof(*init_vm) + - sizeof(init_vm->cpuid.entries[0]) * KVM_MAX_CPUID_ENTRIES, - GFP_KERNEL); - if (!init_vm) - return -ENOMEM; - - if (copy_from_user(init_vm, u64_to_user_ptr(cmd->data), sizeof(*init_vm))) { - ret = -EFAULT; - goto out; - } + if (get_user(nr_user_entries, &user_data->cpuid.nent)) + return -EFAULT; - if (init_vm->cpuid.nent > KVM_MAX_CPUID_ENTRIES) { - ret = -E2BIG; - goto out; - } + if (nr_user_entries > KVM_MAX_CPUID_ENTRIES) + return -E2BIG; - if (copy_from_user(init_vm->cpuid.entries, - u64_to_user_ptr(cmd->data) + sizeof(*init_vm), - flex_array_size(init_vm, cpuid.entries, init_vm->cpuid.nent))) { - ret = -EFAULT; - goto out; - } + init_vm = memdup_user(user_data, + struct_size(user_data, cpuid.entries, nr_user_entries)); + if (IS_ERR(init_vm)) + return PTR_ERR(init_vm); if (memchr_inv(init_vm->reserved, 0, sizeof(init_vm->reserved))) { ret = -EINVAL; @@ -2868,24 +2815,14 @@ static int tdx_td_finalize(struct kvm *kvm, struct kvm_tdx_cmd *cmd) { struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); - guard(mutex)(&kvm->slots_lock); - if (!is_hkid_assigned(kvm_tdx) || kvm_tdx->state == TD_STATE_RUNNABLE) return -EINVAL; - /* - * Pages are pending for KVM_TDX_INIT_MEM_REGION to issue - * TDH.MEM.PAGE.ADD(). - */ - if (atomic64_read(&kvm_tdx->nr_premapped)) - return -EINVAL; cmd->hw_error = tdh_mr_finalize(&kvm_tdx->td); if (tdx_operand_busy(cmd->hw_error)) return -EBUSY; - if (KVM_BUG_ON(cmd->hw_error, kvm)) { - pr_tdx_error(TDH_MR_FINALIZE, cmd->hw_error); + if (TDX_BUG_ON(cmd->hw_error, TDH_MR_FINALIZE, kvm)) return -EIO; - } kvm_tdx->state = TD_STATE_RUNNABLE; /* TD_STATE_RUNNABLE must be set before 'pre_fault_allowed' */ @@ -2894,27 +2831,38 @@ static int tdx_td_finalize(struct kvm *kvm, struct kvm_tdx_cmd *cmd) return 0; } -int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) +static int tdx_get_cmd(void __user *argp, struct kvm_tdx_cmd *cmd) { - struct kvm_tdx_cmd tdx_cmd; - int r; - - if (copy_from_user(&tdx_cmd, argp, sizeof(struct kvm_tdx_cmd))) + if (copy_from_user(cmd, argp, sizeof(*cmd))) return -EFAULT; /* - * Userspace should never set hw_error. It is used to fill - * hardware-defined error by the kernel. + * Userspace should never set hw_error. KVM writes hw_error to report + * hardware-defined error back to userspace. */ - if (tdx_cmd.hw_error) + if (cmd->hw_error) return -EINVAL; - mutex_lock(&kvm->lock); + return 0; +} + +int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) +{ + struct kvm_tdx_cmd tdx_cmd; + int r; + + r = tdx_get_cmd(argp, &tdx_cmd); + if (r) + return r; + + if (tdx_cmd.id == KVM_TDX_CAPABILITIES) + return tdx_get_capabilities(&tdx_cmd); + + CLASS(tdx_vm_state_guard, guard)(kvm); + if (IS_ERR(guard)) + return PTR_ERR(guard); switch (tdx_cmd.id) { - case KVM_TDX_CAPABILITIES: - r = tdx_get_capabilities(&tdx_cmd); - break; case KVM_TDX_INIT_VM: r = tdx_td_init(kvm, &tdx_cmd); break; @@ -2922,15 +2870,12 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) r = tdx_td_finalize(kvm, &tdx_cmd); break; default: - r = -EINVAL; - goto out; + return -EINVAL; } if (copy_to_user(argp, &tdx_cmd, sizeof(struct kvm_tdx_cmd))) - r = -EFAULT; + return -EFAULT; -out: - mutex_unlock(&kvm->lock); return r; } @@ -2972,16 +2917,14 @@ static int tdx_td_vcpu_init(struct kvm_vcpu *vcpu, u64 vcpu_rcx) } err = tdh_vp_create(&kvm_tdx->td, &tdx->vp); - if (KVM_BUG_ON(err, vcpu->kvm)) { + if (TDX_BUG_ON(err, TDH_VP_CREATE, vcpu->kvm)) { ret = -EIO; - pr_tdx_error(TDH_VP_CREATE, err); goto free_tdcx; } for (i = 0; i < kvm_tdx->td.tdcx_nr_pages; i++) { err = tdh_vp_addcx(&tdx->vp, tdx->vp.tdcx_pages[i]); - if (KVM_BUG_ON(err, vcpu->kvm)) { - pr_tdx_error(TDH_VP_ADDCX, err); + if (TDX_BUG_ON(err, TDH_VP_ADDCX, vcpu->kvm)) { /* * Pages already added are reclaimed by the vcpu_free * method, but the rest are freed here. @@ -2994,10 +2937,19 @@ static int tdx_td_vcpu_init(struct kvm_vcpu *vcpu, u64 vcpu_rcx) } } - err = tdh_vp_init(&tdx->vp, vcpu_rcx, vcpu->vcpu_id); - if (KVM_BUG_ON(err, vcpu->kvm)) { - pr_tdx_error(TDH_VP_INIT, err); - return -EIO; + /* + * tdh_vp_init() can take an exclusive lock of the TDR resource inside + * the TDX-Module. The TDR resource is also taken as shared in several + * no-fail MMU paths, which could return TDX_OPERAND_BUSY on contention + * (TDX-Module locks are try-lock implementations with no slow path). + * Take mmu_lock for write to reflect the nature of the lock taken by + * the TDX-Module, and to ensure the no-fail MMU paths succeed, e.g. if + * a concurrent PUNCH_HOLE on guest_memfd triggers removal of SPTEs. + */ + scoped_guard(write_lock, &vcpu->kvm->mmu_lock) { + err = tdh_vp_init(&tdx->vp, vcpu_rcx, vcpu->vcpu_id); + if (TDX_BUG_ON(err, TDH_VP_INIT, vcpu->kvm)) + return -EIO; } vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE; @@ -3016,7 +2968,7 @@ free_tdcx: free_tdvpr: if (tdx->vp.tdvpr_page) __free_page(tdx->vp.tdvpr_page); - tdx->vp.tdvpr_page = 0; + tdx->vp.tdvpr_page = NULL; tdx->vp.tdvpr_pa = 0; return ret; @@ -3054,7 +3006,8 @@ static int tdx_vcpu_get_cpuid_leaf(struct kvm_vcpu *vcpu, u32 leaf, int *entry_i static int tdx_vcpu_get_cpuid(struct kvm_vcpu *vcpu, struct kvm_tdx_cmd *cmd) { - struct kvm_cpuid2 __user *output, *td_cpuid; + struct kvm_cpuid2 __user *output; + struct kvm_cpuid2 *td_cpuid; int r = 0, i = 0, leaf; u32 level; @@ -3167,15 +3120,15 @@ struct tdx_gmem_post_populate_arg { static int tdx_gmem_post_populate(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, void __user *src, int order, void *_arg) { - u64 error_code = PFERR_GUEST_FINAL_MASK | PFERR_PRIVATE_ACCESS; - struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); struct tdx_gmem_post_populate_arg *arg = _arg; - struct kvm_vcpu *vcpu = arg->vcpu; + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); + u64 err, entry, level_state; gpa_t gpa = gfn_to_gpa(gfn); - u8 level = PG_LEVEL_4K; struct page *src_page; int ret, i; - u64 err, entry, level_state; + + if (KVM_BUG_ON(kvm_tdx->page_add_src, kvm)) + return -EIO; /* * Get the source page if it has been faulted in. Return failure if the @@ -3187,49 +3140,29 @@ static int tdx_gmem_post_populate(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, if (ret != 1) return -ENOMEM; - ret = kvm_tdp_map_page(vcpu, gpa, error_code, &level); - if (ret < 0) - goto out; - - /* - * The private mem cannot be zapped after kvm_tdp_map_page() - * because all paths are covered by slots_lock and the - * filemap invalidate lock. Check that they are indeed enough. - */ - if (IS_ENABLED(CONFIG_KVM_PROVE_MMU)) { - scoped_guard(read_lock, &kvm->mmu_lock) { - if (KVM_BUG_ON(!kvm_tdp_mmu_gpa_is_mapped(vcpu, gpa), kvm)) { - ret = -EIO; - goto out; - } - } - } + kvm_tdx->page_add_src = src_page; + ret = kvm_tdp_mmu_map_private_pfn(arg->vcpu, gfn, pfn); + kvm_tdx->page_add_src = NULL; - ret = 0; - err = tdh_mem_page_add(&kvm_tdx->td, gpa, pfn_to_page(pfn), - src_page, &entry, &level_state); - if (err) { - ret = unlikely(tdx_operand_busy(err)) ? -EBUSY : -EIO; - goto out; - } + put_page(src_page); - if (!KVM_BUG_ON(!atomic64_read(&kvm_tdx->nr_premapped), kvm)) - atomic64_dec(&kvm_tdx->nr_premapped); + if (ret || !(arg->flags & KVM_TDX_MEASURE_MEMORY_REGION)) + return ret; - if (arg->flags & KVM_TDX_MEASURE_MEMORY_REGION) { - for (i = 0; i < PAGE_SIZE; i += TDX_EXTENDMR_CHUNKSIZE) { - err = tdh_mr_extend(&kvm_tdx->td, gpa + i, &entry, - &level_state); - if (err) { - ret = -EIO; - break; - } - } + /* + * Note, MR.EXTEND can fail if the S-EPT mapping is somehow removed + * between mapping the pfn and now, but slots_lock prevents memslot + * updates, filemap_invalidate_lock() prevents guest_memfd updates, + * mmu_notifier events can't reach S-EPT entries, and KVM's internal + * zapping flows are mutually exclusive with S-EPT mappings. + */ + for (i = 0; i < PAGE_SIZE; i += TDX_EXTENDMR_CHUNKSIZE) { + err = tdh_mr_extend(&kvm_tdx->td, gpa + i, &entry, &level_state); + if (TDX_BUG_ON_2(err, TDH_MR_EXTEND, entry, level_state, kvm)) + return -EIO; } -out: - put_page(src_page); - return ret; + return 0; } static int tdx_vcpu_init_mem_region(struct kvm_vcpu *vcpu, struct kvm_tdx_cmd *cmd) @@ -3245,8 +3178,6 @@ static int tdx_vcpu_init_mem_region(struct kvm_vcpu *vcpu, struct kvm_tdx_cmd *c if (tdx->state != VCPU_TD_STATE_INITIALIZED) return -EINVAL; - guard(mutex)(&kvm->slots_lock); - /* Once TD is finalized, the initial guest memory is fixed. */ if (kvm_tdx->state == TD_STATE_RUNNABLE) return -EINVAL; @@ -3264,7 +3195,6 @@ static int tdx_vcpu_init_mem_region(struct kvm_vcpu *vcpu, struct kvm_tdx_cmd *c !vt_is_tdx_private_gpa(kvm, region.gpa + (region.nr_pages << PAGE_SHIFT) - 1)) return -EINVAL; - kvm_mmu_reload(vcpu); ret = 0; while (region.nr_pages) { if (signal_pending(current)) { @@ -3301,28 +3231,57 @@ static int tdx_vcpu_init_mem_region(struct kvm_vcpu *vcpu, struct kvm_tdx_cmd *c return ret; } -int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) +int tdx_vcpu_unlocked_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { - struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm); + struct kvm *kvm = vcpu->kvm; + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); struct kvm_tdx_cmd cmd; - int ret; + int r; - if (!is_hkid_assigned(kvm_tdx) || kvm_tdx->state == TD_STATE_RUNNABLE) - return -EINVAL; + r = tdx_get_cmd(argp, &cmd); + if (r) + return r; - if (copy_from_user(&cmd, argp, sizeof(cmd))) - return -EFAULT; + CLASS(tdx_vm_state_guard, guard)(kvm); + if (IS_ERR(guard)) + return PTR_ERR(guard); - if (cmd.hw_error) + if (!is_hkid_assigned(kvm_tdx) || kvm_tdx->state == TD_STATE_RUNNABLE) return -EINVAL; + vcpu_load(vcpu); + switch (cmd.id) { + case KVM_TDX_INIT_MEM_REGION: + r = tdx_vcpu_init_mem_region(vcpu, &cmd); + break; case KVM_TDX_INIT_VCPU: - ret = tdx_vcpu_init(vcpu, &cmd); + r = tdx_vcpu_init(vcpu, &cmd); break; - case KVM_TDX_INIT_MEM_REGION: - ret = tdx_vcpu_init_mem_region(vcpu, &cmd); + default: + r = -ENOIOCTLCMD; break; + } + + vcpu_put(vcpu); + + return r; +} + +int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) +{ + struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm); + struct kvm_tdx_cmd cmd; + int ret; + + if (!is_hkid_assigned(kvm_tdx) || kvm_tdx->state == TD_STATE_RUNNABLE) + return -EINVAL; + + ret = tdx_get_cmd(argp, &cmd); + if (ret) + return ret; + + switch (cmd.id) { case KVM_TDX_GET_CPUID: ret = tdx_vcpu_get_cpuid(vcpu, &cmd); break; @@ -3447,10 +3406,6 @@ static int __init __tdx_bringup(void) /* * Check if MSRs (tdx_uret_msrs) can be saved/restored * before returning to user space. - * - * this_cpu_ptr(user_return_msrs)->registered isn't checked - * because the registration is done at vcpu runtime by - * tdx_user_return_msr_update_cache(). */ tdx_uret_msrs[i].slot = kvm_find_user_return_msr(tdx_uret_msrs[i].msr); if (tdx_uret_msrs[i].slot == -1) { diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h index ca39a9391db1..45b5183ccb36 100644 --- a/arch/x86/kvm/vmx/tdx.h +++ b/arch/x86/kvm/vmx/tdx.h @@ -36,8 +36,12 @@ struct kvm_tdx { struct tdx_td td; - /* For KVM_TDX_INIT_MEM_REGION. */ - atomic64_t nr_premapped; + /* + * Scratch pointer used to pass the source page to tdx_mem_page_add(). + * Protected by slots_lock, and non-NULL only when mapping a private + * pfn via tdx_gmem_post_populate(). + */ + struct page *page_add_src; /* * Prevent vCPUs from TD entry to ensure SEPT zap related SEAMCALLs do @@ -67,7 +71,6 @@ struct vcpu_tdx { u64 vp_enter_ret; enum vcpu_tdx_state state; - bool guest_entered; u64 map_gpa_next; u64 map_gpa_end; diff --git a/arch/x86/kvm/vmx/vmenter.S b/arch/x86/kvm/vmx/vmenter.S index bc255d709d8a..4426d34811fc 100644 --- a/arch/x86/kvm/vmx/vmenter.S +++ b/arch/x86/kvm/vmx/vmenter.S @@ -71,6 +71,7 @@ * @regs: unsigned long * (to guest registers) * @flags: VMX_RUN_VMRESUME: use VMRESUME instead of VMLAUNCH * VMX_RUN_SAVE_SPEC_CTRL: save guest SPEC_CTRL into vmx->spec_ctrl + * VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO: vCPU can access host MMIO * * Returns: * 0 on VM-Exit, 1 on VM-Fail @@ -92,7 +93,7 @@ SYM_FUNC_START(__vmx_vcpu_run) /* Save @vmx for SPEC_CTRL handling */ push %_ASM_ARG1 - /* Save @flags for SPEC_CTRL handling */ + /* Save @flags (used for VMLAUNCH vs. VMRESUME and mitigations). */ push %_ASM_ARG3 /* @@ -101,9 +102,6 @@ SYM_FUNC_START(__vmx_vcpu_run) */ push %_ASM_ARG2 - /* Copy @flags to EBX, _ASM_ARG3 is volatile. */ - mov %_ASM_ARG3L, %ebx - lea (%_ASM_SP), %_ASM_ARG2 call vmx_update_host_rsp @@ -118,13 +116,23 @@ SYM_FUNC_START(__vmx_vcpu_run) * and vmentry. */ mov 2*WORD_SIZE(%_ASM_SP), %_ASM_DI - movl VMX_spec_ctrl(%_ASM_DI), %edi - movl PER_CPU_VAR(x86_spec_ctrl_current), %esi - cmp %edi, %esi +#ifdef CONFIG_X86_64 + mov VMX_spec_ctrl(%rdi), %rdx + cmp PER_CPU_VAR(x86_spec_ctrl_current), %rdx je .Lspec_ctrl_done + movl %edx, %eax + shr $32, %rdx +#else + mov VMX_spec_ctrl(%edi), %eax + mov PER_CPU_VAR(x86_spec_ctrl_current), %ecx + xor %eax, %ecx + mov VMX_spec_ctrl + 4(%edi), %edx + mov PER_CPU_VAR(x86_spec_ctrl_current + 4), %edi + xor %edx, %edi + or %edi, %ecx + je .Lspec_ctrl_done +#endif mov $MSR_IA32_SPEC_CTRL, %ecx - xor %edx, %edx - mov %edi, %eax wrmsr .Lspec_ctrl_done: @@ -137,9 +145,6 @@ SYM_FUNC_START(__vmx_vcpu_run) /* Load @regs to RAX. */ mov (%_ASM_SP), %_ASM_AX - /* Check if vmlaunch or vmresume is needed */ - bt $VMX_RUN_VMRESUME_SHIFT, %ebx - /* Load guest registers. Don't clobber flags. */ mov VCPU_RCX(%_ASM_AX), %_ASM_CX mov VCPU_RDX(%_ASM_AX), %_ASM_DX @@ -160,11 +165,23 @@ SYM_FUNC_START(__vmx_vcpu_run) /* Load guest RAX. This kills the @regs pointer! */ mov VCPU_RAX(%_ASM_AX), %_ASM_AX - /* Clobbers EFLAGS.ZF */ - CLEAR_CPU_BUFFERS - - /* Check EFLAGS.CF from the VMX_RUN_VMRESUME bit test above. */ - jnc .Lvmlaunch + /* + * Note, ALTERNATIVE_2 works in reverse order. If CLEAR_CPU_BUF_VM is + * enabled, do VERW unconditionally. If CPU_BUF_VM_MMIO is enabled, + * check @flags to see if the vCPU has access to host MMIO, and if so, + * do VERW. Else, do nothing (no mitigations needed/enabled). + */ + ALTERNATIVE_2 "", \ + __stringify(testl $VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO, WORD_SIZE(%_ASM_SP); \ + jz .Lskip_mmio_verw; \ + VERW; \ + .Lskip_mmio_verw:), \ + X86_FEATURE_CLEAR_CPU_BUF_VM_MMIO, \ + __stringify(VERW), X86_FEATURE_CLEAR_CPU_BUF_VM + + /* Check @flags to see if VMLAUNCH or VMRESUME is needed. */ + testl $VMX_RUN_VMRESUME, WORD_SIZE(%_ASM_SP) + jz .Lvmlaunch /* * After a successful VMRESUME/VMLAUNCH, control flow "magically" diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 91b6f2f3edc2..4cbe8c84b636 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -203,6 +203,7 @@ module_param(pt_mode, int, S_IRUGO); struct x86_pmu_lbr __ro_after_init vmx_lbr_caps; +#ifdef CONFIG_CPU_MITIGATIONS static DEFINE_STATIC_KEY_FALSE(vmx_l1d_should_flush); static DEFINE_STATIC_KEY_FALSE(vmx_l1d_flush_cond); static DEFINE_MUTEX(vmx_l1d_flush_mutex); @@ -225,7 +226,7 @@ static const struct { #define L1D_CACHE_ORDER 4 static void *vmx_l1d_flush_pages; -static int vmx_setup_l1d_flush(enum vmx_l1d_flush_state l1tf) +static int __vmx_setup_l1d_flush(enum vmx_l1d_flush_state l1tf) { struct page *page; unsigned int i; @@ -302,6 +303,26 @@ static int vmx_setup_l1d_flush(enum vmx_l1d_flush_state l1tf) return 0; } +static int vmx_setup_l1d_flush(void) +{ + /* + * Hand the parameter mitigation value in which was stored in the pre + * module init parser. If no parameter was given, it will contain + * 'auto' which will be turned into the default 'cond' mitigation mode. + */ + return __vmx_setup_l1d_flush(vmentry_l1d_flush_param); +} + +static void vmx_cleanup_l1d_flush(void) +{ + if (vmx_l1d_flush_pages) { + free_pages((unsigned long)vmx_l1d_flush_pages, L1D_CACHE_ORDER); + vmx_l1d_flush_pages = NULL; + } + /* Restore state so sysfs ignores VMX */ + l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_AUTO; +} + static int vmentry_l1d_flush_parse(const char *s) { unsigned int i; @@ -339,7 +360,7 @@ static int vmentry_l1d_flush_set(const char *s, const struct kernel_param *kp) } mutex_lock(&vmx_l1d_flush_mutex); - ret = vmx_setup_l1d_flush(l1tf); + ret = __vmx_setup_l1d_flush(l1tf); mutex_unlock(&vmx_l1d_flush_mutex); return ret; } @@ -352,6 +373,101 @@ static int vmentry_l1d_flush_get(char *s, const struct kernel_param *kp) return sysfs_emit(s, "%s\n", vmentry_l1d_param[l1tf_vmx_mitigation].option); } +/* + * Software based L1D cache flush which is used when microcode providing + * the cache control MSR is not loaded. + * + * The L1D cache is 32 KiB on Nehalem and later microarchitectures, but to + * flush it is required to read in 64 KiB because the replacement algorithm + * is not exactly LRU. This could be sized at runtime via topology + * information but as all relevant affected CPUs have 32KiB L1D cache size + * there is no point in doing so. + */ +static noinstr void vmx_l1d_flush(struct kvm_vcpu *vcpu) +{ + int size = PAGE_SIZE << L1D_CACHE_ORDER; + + if (!static_branch_unlikely(&vmx_l1d_should_flush)) + return; + + /* + * This code is only executed when the flush mode is 'cond' or + * 'always' + */ + if (static_branch_likely(&vmx_l1d_flush_cond)) { + /* + * Clear the per-cpu flush bit, it gets set again if the vCPU + * is reloaded, i.e. if the vCPU is scheduled out or if KVM + * exits to userspace, or if KVM reaches one of the unsafe + * VMEXIT handlers, e.g. if KVM calls into the emulator, + * or from the interrupt handlers. + */ + if (!kvm_get_cpu_l1tf_flush_l1d()) + return; + kvm_clear_cpu_l1tf_flush_l1d(); + } + + vcpu->stat.l1d_flush++; + + if (static_cpu_has(X86_FEATURE_FLUSH_L1D)) { + native_wrmsrq(MSR_IA32_FLUSH_CMD, L1D_FLUSH); + return; + } + + asm volatile( + /* First ensure the pages are in the TLB */ + "xorl %%eax, %%eax\n" + ".Lpopulate_tlb:\n\t" + "movzbl (%[flush_pages], %%" _ASM_AX "), %%ecx\n\t" + "addl $4096, %%eax\n\t" + "cmpl %%eax, %[size]\n\t" + "jne .Lpopulate_tlb\n\t" + "xorl %%eax, %%eax\n\t" + "cpuid\n\t" + /* Now fill the cache */ + "xorl %%eax, %%eax\n" + ".Lfill_cache:\n" + "movzbl (%[flush_pages], %%" _ASM_AX "), %%ecx\n\t" + "addl $64, %%eax\n\t" + "cmpl %%eax, %[size]\n\t" + "jne .Lfill_cache\n\t" + "lfence\n" + :: [flush_pages] "r" (vmx_l1d_flush_pages), + [size] "r" (size) + : "eax", "ebx", "ecx", "edx"); +} + +#else /* CONFIG_CPU_MITIGATIONS*/ +static int vmx_setup_l1d_flush(void) +{ + l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_NEVER; + return 0; +} +static void vmx_cleanup_l1d_flush(void) +{ + l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_AUTO; +} +static __always_inline void vmx_l1d_flush(struct kvm_vcpu *vcpu) +{ + +} +static int vmentry_l1d_flush_set(const char *s, const struct kernel_param *kp) +{ + pr_warn_once("Kernel compiled without mitigations, ignoring vmentry_l1d_flush\n"); + return 0; +} +static int vmentry_l1d_flush_get(char *s, const struct kernel_param *kp) +{ + return sysfs_emit(s, "never\n"); +} +#endif + +static const struct kernel_param_ops vmentry_l1d_flush_ops = { + .set = vmentry_l1d_flush_set, + .get = vmentry_l1d_flush_get, +}; +module_param_cb(vmentry_l1d_flush, &vmentry_l1d_flush_ops, NULL, 0644); + static __always_inline void vmx_disable_fb_clear(struct vcpu_vmx *vmx) { u64 msr; @@ -404,12 +520,6 @@ static void vmx_update_fb_clear_dis(struct kvm_vcpu *vcpu, struct vcpu_vmx *vmx) vmx->disable_fb_clear = false; } -static const struct kernel_param_ops vmentry_l1d_flush_ops = { - .set = vmentry_l1d_flush_set, - .get = vmentry_l1d_flush_get, -}; -module_param_cb(vmentry_l1d_flush, &vmentry_l1d_flush_ops, NULL, 0644); - static u32 vmx_segment_access_rights(struct kvm_segment *var); void vmx_vmexit(void); @@ -752,7 +862,7 @@ static void __loaded_vmcs_clear(void *arg) loaded_vmcs->launched = 0; } -void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs) +static void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs) { int cpu = loaded_vmcs->cpu; @@ -903,7 +1013,7 @@ unsigned int __vmx_vcpu_run_flags(struct vcpu_vmx *vmx) if (!msr_write_intercepted(vmx, MSR_IA32_SPEC_CTRL)) flags |= VMX_RUN_SAVE_SPEC_CTRL; - if (static_branch_unlikely(&cpu_buf_vm_clear) && + if (cpu_feature_enabled(X86_FEATURE_CLEAR_CPU_BUF_VM_MMIO) && kvm_vcpu_can_access_host_mmio(&vmx->vcpu)) flags |= VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO; @@ -3219,6 +3329,40 @@ static inline int vmx_get_current_vpid(struct kvm_vcpu *vcpu) return to_vmx(vcpu)->vpid; } +static u64 construct_eptp(hpa_t root_hpa) +{ + u64 eptp = root_hpa | VMX_EPTP_MT_WB; + struct kvm_mmu_page *root; + + if (kvm_mmu_is_dummy_root(root_hpa)) + return eptp | VMX_EPTP_PWL_4; + + /* + * EPT roots should always have an associated MMU page. Return a "bad" + * EPTP to induce VM-Fail instead of continuing on in a unknown state. + */ + root = root_to_sp(root_hpa); + if (WARN_ON_ONCE(!root)) + return INVALID_PAGE; + + eptp |= (root->role.level == 5) ? VMX_EPTP_PWL_5 : VMX_EPTP_PWL_4; + + if (enable_ept_ad_bits && !root->role.ad_disabled) + eptp |= VMX_EPTP_AD_ENABLE_BIT; + + return eptp; +} + +static void vmx_flush_tlb_ept_root(hpa_t root_hpa) +{ + u64 eptp = construct_eptp(root_hpa); + + if (VALID_PAGE(eptp)) + ept_sync_context(eptp); + else + ept_sync_global(); +} + void vmx_flush_tlb_current(struct kvm_vcpu *vcpu) { struct kvm_mmu *mmu = vcpu->arch.mmu; @@ -3229,8 +3373,7 @@ void vmx_flush_tlb_current(struct kvm_vcpu *vcpu) return; if (enable_ept) - ept_sync_context(construct_eptp(vcpu, root_hpa, - mmu->root_role.level)); + vmx_flush_tlb_ept_root(root_hpa); else vpid_sync_context(vmx_get_current_vpid(vcpu)); } @@ -3396,30 +3539,16 @@ static int vmx_get_max_ept_level(void) return 4; } -u64 construct_eptp(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level) -{ - u64 eptp = VMX_EPTP_MT_WB; - - eptp |= (root_level == 5) ? VMX_EPTP_PWL_5 : VMX_EPTP_PWL_4; - - if (enable_ept_ad_bits && - (!is_guest_mode(vcpu) || nested_ept_ad_enabled(vcpu))) - eptp |= VMX_EPTP_AD_ENABLE_BIT; - eptp |= root_hpa; - - return eptp; -} - void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level) { struct kvm *kvm = vcpu->kvm; bool update_guest_cr3 = true; unsigned long guest_cr3; - u64 eptp; if (enable_ept) { - eptp = construct_eptp(vcpu, root_hpa, root_level); - vmcs_write64(EPT_POINTER, eptp); + KVM_MMU_WARN_ON(root_to_sp(root_hpa) && + root_level != root_to_sp(root_hpa)->role.level); + vmcs_write64(EPT_POINTER, construct_eptp(root_hpa)); hv_track_root_tdp(vcpu, root_hpa); @@ -6631,15 +6760,8 @@ static int __vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) return kvm_vmx_exit_handlers[exit_handler_index](vcpu); unexpected_vmexit: - vcpu_unimpl(vcpu, "vmx: unexpected exit reason 0x%x\n", - exit_reason.full); dump_vmcs(vcpu); - vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; - vcpu->run->internal.suberror = - KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON; - vcpu->run->internal.ndata = 2; - vcpu->run->internal.data[0] = exit_reason.full; - vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu; + kvm_prepare_unexpected_reason_exit(vcpu, exit_reason.full); return 0; } @@ -6661,77 +6783,6 @@ int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) return ret; } -/* - * Software based L1D cache flush which is used when microcode providing - * the cache control MSR is not loaded. - * - * The L1D cache is 32 KiB on Nehalem and later microarchitectures, but to - * flush it is required to read in 64 KiB because the replacement algorithm - * is not exactly LRU. This could be sized at runtime via topology - * information but as all relevant affected CPUs have 32KiB L1D cache size - * there is no point in doing so. - */ -static noinstr void vmx_l1d_flush(struct kvm_vcpu *vcpu) -{ - int size = PAGE_SIZE << L1D_CACHE_ORDER; - - /* - * This code is only executed when the flush mode is 'cond' or - * 'always' - */ - if (static_branch_likely(&vmx_l1d_flush_cond)) { - bool flush_l1d; - - /* - * Clear the per-vcpu flush bit, it gets set again if the vCPU - * is reloaded, i.e. if the vCPU is scheduled out or if KVM - * exits to userspace, or if KVM reaches one of the unsafe - * VMEXIT handlers, e.g. if KVM calls into the emulator. - */ - flush_l1d = vcpu->arch.l1tf_flush_l1d; - vcpu->arch.l1tf_flush_l1d = false; - - /* - * Clear the per-cpu flush bit, it gets set again from - * the interrupt handlers. - */ - flush_l1d |= kvm_get_cpu_l1tf_flush_l1d(); - kvm_clear_cpu_l1tf_flush_l1d(); - - if (!flush_l1d) - return; - } - - vcpu->stat.l1d_flush++; - - if (static_cpu_has(X86_FEATURE_FLUSH_L1D)) { - native_wrmsrq(MSR_IA32_FLUSH_CMD, L1D_FLUSH); - return; - } - - asm volatile( - /* First ensure the pages are in the TLB */ - "xorl %%eax, %%eax\n" - ".Lpopulate_tlb:\n\t" - "movzbl (%[flush_pages], %%" _ASM_AX "), %%ecx\n\t" - "addl $4096, %%eax\n\t" - "cmpl %%eax, %[size]\n\t" - "jne .Lpopulate_tlb\n\t" - "xorl %%eax, %%eax\n\t" - "cpuid\n\t" - /* Now fill the cache */ - "xorl %%eax, %%eax\n" - ".Lfill_cache:\n" - "movzbl (%[flush_pages], %%" _ASM_AX "), %%ecx\n\t" - "addl $64, %%eax\n\t" - "cmpl %%eax, %[size]\n\t" - "jne .Lfill_cache\n\t" - "lfence\n" - :: [flush_pages] "r" (vmx_l1d_flush_pages), - [size] "r" (size) - : "eax", "ebx", "ecx", "edx"); -} - void vmx_update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr) { struct vmcs12 *vmcs12 = get_vmcs12(vcpu); @@ -7050,10 +7101,19 @@ void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu) if (to_vt(vcpu)->emulation_required) return; - if (vmx_get_exit_reason(vcpu).basic == EXIT_REASON_EXTERNAL_INTERRUPT) + switch (vmx_get_exit_reason(vcpu).basic) { + case EXIT_REASON_EXTERNAL_INTERRUPT: handle_external_interrupt_irqoff(vcpu, vmx_get_intr_info(vcpu)); - else if (vmx_get_exit_reason(vcpu).basic == EXIT_REASON_EXCEPTION_NMI) + break; + case EXIT_REASON_EXCEPTION_NMI: handle_exception_irqoff(vcpu, vmx_get_intr_info(vcpu)); + break; + case EXIT_REASON_MCE_DURING_VMENTRY: + kvm_machine_check(); + break; + default: + break; + } } /* @@ -7328,21 +7388,7 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu, guest_state_enter_irqoff(); - /* - * L1D Flush includes CPU buffer clear to mitigate MDS, but VERW - * mitigation for MDS is done late in VMentry and is still - * executed in spite of L1D Flush. This is because an extra VERW - * should not matter much after the big hammer L1D Flush. - * - * cpu_buf_vm_clear is used when system is not vulnerable to MDS/TAA, - * and is affected by MMIO Stale Data. In such cases mitigation in only - * needed against an MMIO capable guest. - */ - if (static_branch_unlikely(&vmx_l1d_should_flush)) - vmx_l1d_flush(vcpu); - else if (static_branch_unlikely(&cpu_buf_vm_clear) && - (flags & VMX_RUN_CLEAR_CPU_BUFFERS_FOR_MMIO)) - x86_clear_cpu_buffers(); + vmx_l1d_flush(vcpu); vmx_disable_fb_clear(vmx); @@ -7454,8 +7500,6 @@ fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags) if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) vmx_set_interrupt_shadow(vcpu, 0); - kvm_load_guest_xsave_state(vcpu); - pt_guest_enter(vmx); atomic_switch_perf_msrs(vmx); @@ -7499,8 +7543,6 @@ fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags) pt_guest_exit(vmx); - kvm_load_host_xsave_state(vcpu); - if (is_guest_mode(vcpu)) { /* * Track VMLAUNCH/VMRESUME that have made past guest state @@ -7516,9 +7558,6 @@ fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags) if (unlikely(vmx->fail)) return EXIT_FASTPATH_NONE; - if (unlikely((u16)vmx_get_exit_reason(vcpu).basic == EXIT_REASON_MCE_DURING_VMENTRY)) - kvm_machine_check(); - trace_kvm_exit(vcpu, KVM_ISA_VMX); if (unlikely(vmx_get_exit_reason(vcpu).failed_vmentry)) @@ -8679,16 +8718,6 @@ __init int vmx_hardware_setup(void) return r; } -static void vmx_cleanup_l1d_flush(void) -{ - if (vmx_l1d_flush_pages) { - free_pages((unsigned long)vmx_l1d_flush_pages, L1D_CACHE_ORDER); - vmx_l1d_flush_pages = NULL; - } - /* Restore state so sysfs ignores VMX */ - l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_AUTO; -} - void vmx_exit(void) { allow_smaller_maxphyaddr = false; @@ -8724,14 +8753,8 @@ int __init vmx_init(void) if (r) return r; - /* - * Must be called after common x86 init so enable_ept is properly set - * up. Hand the parameter mitigation value in which was stored in - * the pre module init parser. If no parameter was given, it will - * contain 'auto' which will be turned into the default 'cond' - * mitigation mode. - */ - r = vmx_setup_l1d_flush(vmentry_l1d_flush_param); + /* Must be called after common x86 init so enable_ept is setup. */ + r = vmx_setup_l1d_flush(); if (r) goto err_l1d_flush; diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index ea93121029f9..bc3ed3145d7e 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -369,7 +369,6 @@ void set_cr4_guest_host_mask(struct vcpu_vmx *vmx); void ept_save_pdptrs(struct kvm_vcpu *vcpu); void vmx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg); void __vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg); -u64 construct_eptp(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level); bool vmx_guest_inject_ac(struct kvm_vcpu *vcpu); void vmx_update_exception_bitmap(struct kvm_vcpu *vcpu); @@ -681,7 +680,6 @@ struct vmcs *alloc_vmcs_cpu(bool shadow, int cpu, gfp_t flags); void free_vmcs(struct vmcs *vmcs); int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs); void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs); -void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs); static inline struct vmcs *alloc_vmcs(bool shadow) { diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h index 9697368d65b3..d09abeac2b56 100644 --- a/arch/x86/kvm/vmx/x86_ops.h +++ b/arch/x86/kvm/vmx/x86_ops.h @@ -73,7 +73,6 @@ void vmx_get_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt); void vmx_set_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt); void vmx_get_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt); void vmx_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt); -void vmx_set_dr6(struct kvm_vcpu *vcpu, unsigned long val); void vmx_set_dr7(struct kvm_vcpu *vcpu, unsigned long val); void vmx_sync_dirty_debug_regs(struct kvm_vcpu *vcpu); void vmx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg); @@ -149,6 +148,7 @@ int tdx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr); int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr); int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp); +int tdx_vcpu_unlocked_ioctl(struct kvm_vcpu *vcpu, void __user *argp); void tdx_flush_tlb_current(struct kvm_vcpu *vcpu); void tdx_flush_tlb_all(struct kvm_vcpu *vcpu); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c9c2aa6f4705..0c6d899d53dd 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -159,9 +159,6 @@ EXPORT_SYMBOL_FOR_KVM_INTERNAL(report_ignored_msrs); unsigned int min_timer_period_us = 200; module_param(min_timer_period_us, uint, 0644); -static bool __read_mostly kvmclock_periodic_sync = true; -module_param(kvmclock_periodic_sync, bool, 0444); - /* tsc tolerance in parts per million - default to 1/2 of the NTP threshold */ static u32 __read_mostly tsc_tolerance_ppm = 250; module_param(tsc_tolerance_ppm, uint, 0644); @@ -212,7 +209,7 @@ struct kvm_user_return_msrs { u32 __read_mostly kvm_nr_uret_msrs; EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_nr_uret_msrs); static u32 __read_mostly kvm_uret_msrs_list[KVM_MAX_NR_USER_RETURN_MSRS]; -static struct kvm_user_return_msrs __percpu *user_return_msrs; +static DEFINE_PER_CPU(struct kvm_user_return_msrs, user_return_msrs); #define KVM_SUPPORTED_XCR0 (XFEATURE_MASK_FP | XFEATURE_MASK_SSE \ | XFEATURE_MASK_YMM | XFEATURE_MASK_BNDREGS \ @@ -575,24 +572,26 @@ static inline void kvm_async_pf_hash_reset(struct kvm_vcpu *vcpu) vcpu->arch.apf.gfns[i] = ~0; } +static void kvm_destroy_user_return_msrs(void) +{ + int cpu; + + for_each_possible_cpu(cpu) + WARN_ON_ONCE(per_cpu(user_return_msrs, cpu).registered); + + kvm_nr_uret_msrs = 0; +} + static void kvm_on_user_return(struct user_return_notifier *urn) { unsigned slot; struct kvm_user_return_msrs *msrs = container_of(urn, struct kvm_user_return_msrs, urn); struct kvm_user_return_msr_values *values; - unsigned long flags; - /* - * Disabling irqs at this point since the following code could be - * interrupted and executed through kvm_arch_disable_virtualization_cpu() - */ - local_irq_save(flags); - if (msrs->registered) { - msrs->registered = false; - user_return_notifier_unregister(urn); - } - local_irq_restore(flags); + msrs->registered = false; + user_return_notifier_unregister(urn); + for (slot = 0; slot < kvm_nr_uret_msrs; ++slot) { values = &msrs->values[slot]; if (values->host != values->curr) { @@ -643,7 +642,7 @@ EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_find_user_return_msr); static void kvm_user_return_msr_cpu_online(void) { - struct kvm_user_return_msrs *msrs = this_cpu_ptr(user_return_msrs); + struct kvm_user_return_msrs *msrs = this_cpu_ptr(&user_return_msrs); u64 value; int i; @@ -665,7 +664,7 @@ static void kvm_user_return_register_notifier(struct kvm_user_return_msrs *msrs) int kvm_set_user_return_msr(unsigned slot, u64 value, u64 mask) { - struct kvm_user_return_msrs *msrs = this_cpu_ptr(user_return_msrs); + struct kvm_user_return_msrs *msrs = this_cpu_ptr(&user_return_msrs); int err; value = (value & mask) | (msrs->values[slot].host & ~mask); @@ -681,24 +680,15 @@ int kvm_set_user_return_msr(unsigned slot, u64 value, u64 mask) } EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_set_user_return_msr); -void kvm_user_return_msr_update_cache(unsigned int slot, u64 value) -{ - struct kvm_user_return_msrs *msrs = this_cpu_ptr(user_return_msrs); - - msrs->values[slot].curr = value; - kvm_user_return_register_notifier(msrs); -} -EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_user_return_msr_update_cache); - u64 kvm_get_user_return_msr(unsigned int slot) { - return this_cpu_ptr(user_return_msrs)->values[slot].curr; + return this_cpu_ptr(&user_return_msrs)->values[slot].curr; } EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_get_user_return_msr); static void drop_user_return_notifiers(void) { - struct kvm_user_return_msrs *msrs = this_cpu_ptr(user_return_msrs); + struct kvm_user_return_msrs *msrs = this_cpu_ptr(&user_return_msrs); if (msrs->registered) kvm_on_user_return(&msrs->urn); @@ -1045,6 +1035,13 @@ bool kvm_require_dr(struct kvm_vcpu *vcpu, int dr) } EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_require_dr); +static bool kvm_pv_async_pf_enabled(struct kvm_vcpu *vcpu) +{ + u64 mask = KVM_ASYNC_PF_ENABLED | KVM_ASYNC_PF_DELIVERY_AS_INT; + + return (vcpu->arch.apf.msr_en_val & mask) == mask; +} + static inline u64 pdptr_rsvd_bits(struct kvm_vcpu *vcpu) { return vcpu->arch.reserved_gpa_bits | rsvd_bits(5, 8) | rsvd_bits(1, 2); @@ -1137,15 +1134,20 @@ void kvm_post_set_cr0(struct kvm_vcpu *vcpu, unsigned long old_cr0, unsigned lon } if ((cr0 ^ old_cr0) & X86_CR0_PG) { - kvm_clear_async_pf_completion_queue(vcpu); - kvm_async_pf_hash_reset(vcpu); - /* * Clearing CR0.PG is defined to flush the TLB from the guest's * perspective. */ if (!(cr0 & X86_CR0_PG)) kvm_make_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu); + /* + * Check for async #PF completion events when enabling paging, + * as the vCPU may have previously encountered async #PFs (it's + * entirely legal for the guest to toggle paging on/off without + * waiting for the async #PF queue to drain). + */ + else if (kvm_pv_async_pf_enabled(vcpu)) + kvm_make_request(KVM_REQ_APF_READY, vcpu); } if ((cr0 ^ old_cr0) & KVM_MMU_CR0_ROLE_BITS) @@ -1203,20 +1205,27 @@ void kvm_lmsw(struct kvm_vcpu *vcpu, unsigned long msw) } EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_lmsw); -void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu) +static void kvm_load_xfeatures(struct kvm_vcpu *vcpu, bool load_guest) { if (vcpu->arch.guest_state_protected) return; - if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) { + if (!kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) + return; - if (vcpu->arch.xcr0 != kvm_host.xcr0) - xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0); + if (vcpu->arch.xcr0 != kvm_host.xcr0) + xsetbv(XCR_XFEATURE_ENABLED_MASK, + load_guest ? vcpu->arch.xcr0 : kvm_host.xcr0); - if (guest_cpu_cap_has(vcpu, X86_FEATURE_XSAVES) && - vcpu->arch.ia32_xss != kvm_host.xss) - wrmsrq(MSR_IA32_XSS, vcpu->arch.ia32_xss); - } + if (guest_cpu_cap_has(vcpu, X86_FEATURE_XSAVES) && + vcpu->arch.ia32_xss != kvm_host.xss) + wrmsrq(MSR_IA32_XSS, load_guest ? vcpu->arch.ia32_xss : kvm_host.xss); +} + +static void kvm_load_guest_pkru(struct kvm_vcpu *vcpu) +{ + if (vcpu->arch.guest_state_protected) + return; if (cpu_feature_enabled(X86_FEATURE_PKU) && vcpu->arch.pkru != vcpu->arch.host_pkru && @@ -1224,9 +1233,8 @@ void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu) kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE))) wrpkru(vcpu->arch.pkru); } -EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_load_guest_xsave_state); -void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu) +static void kvm_load_host_pkru(struct kvm_vcpu *vcpu) { if (vcpu->arch.guest_state_protected) return; @@ -1238,19 +1246,7 @@ void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu) if (vcpu->arch.pkru != vcpu->arch.host_pkru) wrpkru(vcpu->arch.host_pkru); } - - if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) { - - if (vcpu->arch.xcr0 != kvm_host.xcr0) - xsetbv(XCR_XFEATURE_ENABLED_MASK, kvm_host.xcr0); - - if (guest_cpu_cap_has(vcpu, X86_FEATURE_XSAVES) && - vcpu->arch.ia32_xss != kvm_host.xss) - wrmsrq(MSR_IA32_XSS, kvm_host.xss); - } - } -EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_load_host_xsave_state); #ifdef CONFIG_X86_64 static inline u64 kvm_guest_supported_xfd(struct kvm_vcpu *vcpu) @@ -3505,27 +3501,17 @@ uint64_t kvm_get_wall_clock_epoch(struct kvm *kvm) /* * kvmclock updates which are isolated to a given vcpu, such as * vcpu->cpu migration, should not allow system_timestamp from - * the rest of the vcpus to remain static. Otherwise ntp frequency - * correction applies to one vcpu's system_timestamp but not - * the others. + * the rest of the vcpus to remain static. * * So in those cases, request a kvmclock update for all vcpus. - * We need to rate-limit these requests though, as they can - * considerably slow guests that have a large number of vcpus. - * The time for a remote vcpu to update its kvmclock is bound - * by the delay we use to rate-limit the updates. + * The worst case for a remote vcpu to update its kvmclock + * is then bounded by maximum nohz sleep latency. */ - -#define KVMCLOCK_UPDATE_DELAY msecs_to_jiffies(100) - -static void kvmclock_update_fn(struct work_struct *work) +static void kvm_gen_kvmclock_update(struct kvm_vcpu *v) { unsigned long i; - struct delayed_work *dwork = to_delayed_work(work); - struct kvm_arch *ka = container_of(dwork, struct kvm_arch, - kvmclock_update_work); - struct kvm *kvm = container_of(ka, struct kvm, arch); struct kvm_vcpu *vcpu; + struct kvm *kvm = v->kvm; kvm_for_each_vcpu(i, vcpu, kvm) { kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu); @@ -3533,29 +3519,6 @@ static void kvmclock_update_fn(struct work_struct *work) } } -static void kvm_gen_kvmclock_update(struct kvm_vcpu *v) -{ - struct kvm *kvm = v->kvm; - - kvm_make_request(KVM_REQ_CLOCK_UPDATE, v); - schedule_delayed_work(&kvm->arch.kvmclock_update_work, - KVMCLOCK_UPDATE_DELAY); -} - -#define KVMCLOCK_SYNC_PERIOD (300 * HZ) - -static void kvmclock_sync_fn(struct work_struct *work) -{ - struct delayed_work *dwork = to_delayed_work(work); - struct kvm_arch *ka = container_of(dwork, struct kvm_arch, - kvmclock_sync_work); - struct kvm *kvm = container_of(ka, struct kvm, arch); - - schedule_delayed_work(&kvm->arch.kvmclock_update_work, 0); - schedule_delayed_work(&kvm->arch.kvmclock_sync_work, - KVMCLOCK_SYNC_PERIOD); -} - /* These helpers are safe iff @msr is known to be an MCx bank MSR. */ static bool is_mci_control_msr(u32 msr) { @@ -3650,13 +3613,6 @@ static int set_msr_mce(struct kvm_vcpu *vcpu, struct msr_data *msr_info) return 0; } -static inline bool kvm_pv_async_pf_enabled(struct kvm_vcpu *vcpu) -{ - u64 mask = KVM_ASYNC_PF_ENABLED | KVM_ASYNC_PF_DELIVERY_AS_INT; - - return (vcpu->arch.apf.msr_en_val & mask) == mask; -} - static int kvm_pv_enable_async_pf(struct kvm_vcpu *vcpu, u64 data) { gpa_t gpa = data & ~0x3f; @@ -4182,7 +4138,12 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) if (!guest_pv_has(vcpu, KVM_FEATURE_ASYNC_PF_INT)) return 1; if (data & 0x1) { - vcpu->arch.apf.pageready_pending = false; + /* + * Pairs with the smp_mb__after_atomic() in + * kvm_arch_async_page_present_queued(). + */ + smp_store_mb(vcpu->arch.apf.pageready_pending, false); + kvm_check_async_pf_completion(vcpu); } break; @@ -5188,7 +5149,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) { struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); - vcpu->arch.l1tf_flush_l1d = true; + kvm_request_l1tf_flush_l1d(); if (vcpu->scheduled_out && pmu->version && pmu->event_count) { pmu->need_cleanup = true; @@ -7239,6 +7200,19 @@ static int kvm_vm_ioctl_set_clock(struct kvm *kvm, void __user *argp) return 0; } +long kvm_arch_vcpu_unlocked_ioctl(struct file *filp, unsigned int ioctl, + unsigned long arg) +{ + struct kvm_vcpu *vcpu = filp->private_data; + void __user *argp = (void __user *)arg; + + if (ioctl == KVM_MEMORY_ENCRYPT_OP && + kvm_x86_ops.vcpu_mem_enc_unlocked_ioctl) + return kvm_x86_call(vcpu_mem_enc_unlocked_ioctl)(vcpu, argp); + + return -ENOIOCTLCMD; +} + int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { struct kvm *kvm = filp->private_data; @@ -7998,7 +7972,7 @@ int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu, gva_t addr, void *val, unsigned int bytes, struct x86_exception *exception) { /* kvm_write_guest_virt_system can pull in tons of pages. */ - vcpu->arch.l1tf_flush_l1d = true; + kvm_request_l1tf_flush_l1d(); return kvm_write_guest_virt_helper(addr, val, bytes, vcpu, PFERR_WRITE_MASK, exception); @@ -8842,6 +8816,14 @@ static void emulator_triple_fault(struct x86_emulate_ctxt *ctxt) kvm_make_request(KVM_REQ_TRIPLE_FAULT, emul_to_vcpu(ctxt)); } +static int emulator_get_xcr(struct x86_emulate_ctxt *ctxt, u32 index, u64 *xcr) +{ + if (index != XCR_XFEATURE_ENABLED_MASK) + return 1; + *xcr = emul_to_vcpu(ctxt)->arch.xcr0; + return 0; +} + static int emulator_set_xcr(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr) { return __kvm_set_xcr(emul_to_vcpu(ctxt), index, xcr); @@ -8914,6 +8896,7 @@ static const struct x86_emulate_ops emulate_ops = { .is_smm = emulator_is_smm, .leave_smm = emulator_leave_smm, .triple_fault = emulator_triple_fault, + .get_xcr = emulator_get_xcr, .set_xcr = emulator_set_xcr, .get_untagged_addr = emulator_get_untagged_addr, .is_canonical_addr = emulator_is_canonical_addr, @@ -9109,6 +9092,18 @@ void kvm_prepare_event_vectoring_exit(struct kvm_vcpu *vcpu, gpa_t gpa) } EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_prepare_event_vectoring_exit); +void kvm_prepare_unexpected_reason_exit(struct kvm_vcpu *vcpu, u64 exit_reason) +{ + vcpu_unimpl(vcpu, "unexpected exit reason 0x%llx\n", exit_reason); + + vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_UNEXPECTED_EXIT_REASON; + vcpu->run->internal.ndata = 2; + vcpu->run->internal.data[0] = exit_reason; + vcpu->run->internal.data[1] = vcpu->arch.last_vmentry_cpu; +} +EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_prepare_unexpected_reason_exit); + static int handle_emulation_failure(struct kvm_vcpu *vcpu, int emulation_type) { struct kvm *kvm = vcpu->kvm; @@ -9337,6 +9332,23 @@ static bool is_vmware_backdoor_opcode(struct x86_emulate_ctxt *ctxt) return false; } +static bool is_soft_int_instruction(struct x86_emulate_ctxt *ctxt, + int emulation_type) +{ + u8 vector = EMULTYPE_GET_SOFT_INT_VECTOR(emulation_type); + + switch (ctxt->b) { + case 0xcc: + return vector == BP_VECTOR; + case 0xcd: + return vector == ctxt->src.val; + case 0xce: + return vector == OF_VECTOR; + default: + return false; + } +} + /* * Decode an instruction for emulation. The caller is responsible for handling * code breakpoints. Note, manually detecting code breakpoints is unnecessary @@ -9394,7 +9406,7 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, return handle_emulation_failure(vcpu, emulation_type); } - vcpu->arch.l1tf_flush_l1d = true; + kvm_request_l1tf_flush_l1d(); if (!(emulation_type & EMULTYPE_NO_DECODE)) { kvm_clear_exception_queue(vcpu); @@ -9447,6 +9459,10 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, * injecting single-step #DBs. */ if (emulation_type & EMULTYPE_SKIP) { + if (emulation_type & EMULTYPE_SKIP_SOFT_INT && + !is_soft_int_instruction(ctxt, emulation_type)) + return 0; + if (ctxt->mode != X86EMUL_MODE_PROT64) ctxt->eip = (u32)ctxt->_eip; else @@ -10031,17 +10047,9 @@ int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops) return -ENOMEM; } - user_return_msrs = alloc_percpu(struct kvm_user_return_msrs); - if (!user_return_msrs) { - pr_err("failed to allocate percpu kvm_user_return_msrs\n"); - r = -ENOMEM; - goto out_free_x86_emulator_cache; - } - kvm_nr_uret_msrs = 0; - r = kvm_mmu_vendor_module_init(); if (r) - goto out_free_percpu; + goto out_free_x86_emulator_cache; kvm_caps.supported_vm_types = BIT(KVM_X86_DEFAULT_VM); kvm_caps.supported_mce_cap = MCG_CTL_P | MCG_SER_P; @@ -10066,6 +10074,8 @@ int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops) if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES)) rdmsrq(MSR_IA32_ARCH_CAPABILITIES, kvm_host.arch_capabilities); + WARN_ON_ONCE(kvm_nr_uret_msrs); + r = ops->hardware_setup(); if (r != 0) goto out_mmu_exit; @@ -10138,9 +10148,8 @@ out_unwind_ops: kvm_x86_ops.enable_virtualization_cpu = NULL; kvm_x86_call(hardware_unsetup)(); out_mmu_exit: + kvm_destroy_user_return_msrs(); kvm_mmu_vendor_module_exit(); -out_free_percpu: - free_percpu(user_return_msrs); out_free_x86_emulator_cache: kmem_cache_destroy(x86_emulator_cache); return r; @@ -10168,8 +10177,8 @@ void kvm_x86_vendor_exit(void) cancel_work_sync(&pvclock_gtod_work); #endif kvm_x86_call(hardware_unsetup)(); + kvm_destroy_user_return_msrs(); kvm_mmu_vendor_module_exit(); - free_percpu(user_return_msrs); kmem_cache_destroy(x86_emulator_cache); #ifdef CONFIG_KVM_XEN static_key_deferred_flush(&kvm_xen_enabled); @@ -11291,6 +11300,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) if (vcpu->arch.guest_fpu.xfd_err) wrmsrq(MSR_IA32_XFD_ERR, vcpu->arch.guest_fpu.xfd_err); + kvm_load_xfeatures(vcpu, true); + if (unlikely(vcpu->arch.switch_db_regs && !(vcpu->arch.switch_db_regs & KVM_DEBUGREG_AUTO_SWITCH))) { set_debugreg(DR7_FIXED_1, 7); @@ -11319,6 +11330,12 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) guest_timing_enter_irqoff(); + /* + * Swap PKRU with hardware breakpoints disabled to minimize the number + * of flows where non-KVM code can run with guest state loaded. + */ + kvm_load_guest_pkru(vcpu); + for (;;) { /* * Assert that vCPU vs. VM APICv state is consistent. An APICv @@ -11347,6 +11364,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) ++vcpu->stat.exits; } + kvm_load_host_pkru(vcpu); + /* * Do this here before restoring debug registers on the host. And * since we do this before handling the vmexit, a DR access vmexit @@ -11377,6 +11396,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) vcpu->mode = OUTSIDE_GUEST_MODE; smp_wmb(); + kvm_load_xfeatures(vcpu, false); + /* * Sync xfd before calling handle_exit_irqoff() which may * rely on the fact that guest_fpu::xfd is up-to-date (e.g. @@ -12734,8 +12755,6 @@ fail_mmu_destroy: void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) { - struct kvm *kvm = vcpu->kvm; - if (mutex_lock_killable(&vcpu->mutex)) return; vcpu_load(vcpu); @@ -12746,10 +12765,6 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) vcpu->arch.msr_kvm_poll_control = 1; mutex_unlock(&vcpu->mutex); - - if (kvmclock_periodic_sync && vcpu->vcpu_idx == 0) - schedule_delayed_work(&kvm->arch.kvmclock_sync_work, - KVMCLOCK_SYNC_PERIOD); } void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) @@ -13088,7 +13103,21 @@ int kvm_arch_enable_virtualization_cpu(void) void kvm_arch_disable_virtualization_cpu(void) { kvm_x86_call(disable_virtualization_cpu)(); - drop_user_return_notifiers(); + + /* + * Leave the user-return notifiers as-is when disabling virtualization + * for reboot, i.e. when disabling via IPI function call, and instead + * pin kvm.ko (if it's a module) to defend against use-after-free (in + * the *very* unlikely scenario module unload is racing with reboot). + * On a forced reboot, tasks aren't frozen before shutdown, and so KVM + * could be actively modifying user-return MSR state when the IPI to + * disable virtualization arrives. Handle the extreme edge case here + * instead of trying to account for it in the normal flows. + */ + if (in_task() || WARN_ON_ONCE(!kvm_rebooting)) + drop_user_return_notifiers(); + else + __module_get(THIS_MODULE); } bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu) @@ -13160,9 +13189,6 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) kvm->arch.hv_root_tdp = INVALID_PAGE; #endif - INIT_DELAYED_WORK(&kvm->arch.kvmclock_update_work, kvmclock_update_fn); - INIT_DELAYED_WORK(&kvm->arch.kvmclock_sync_work, kvmclock_sync_fn); - kvm_apicv_init(kvm); kvm_hv_init_vm(kvm); kvm_xen_init_vm(kvm); @@ -13269,9 +13295,6 @@ void kvm_arch_pre_destroy_vm(struct kvm *kvm) * is unsafe, i.e. will lead to use-after-free. The PIT also needs to * be stopped before IRQ routing is freed. */ - cancel_delayed_work_sync(&kvm->arch.kvmclock_sync_work); - cancel_delayed_work_sync(&kvm->arch.kvmclock_update_work); - #ifdef CONFIG_KVM_IOAPIC kvm_free_pit(kvm); #endif @@ -13888,7 +13911,7 @@ void kvm_arch_async_page_present(struct kvm_vcpu *vcpu, if ((work->wakeup_all || work->notpresent_injected) && kvm_pv_async_pf_enabled(vcpu) && !apf_put_user_ready(vcpu, work->arch.token)) { - vcpu->arch.apf.pageready_pending = true; + WRITE_ONCE(vcpu->arch.apf.pageready_pending, true); kvm_apic_set_irq(vcpu, &irq, NULL); } @@ -13899,7 +13922,11 @@ void kvm_arch_async_page_present(struct kvm_vcpu *vcpu, void kvm_arch_async_page_present_queued(struct kvm_vcpu *vcpu) { kvm_make_request(KVM_REQ_APF_READY, vcpu); - if (!vcpu->arch.apf.pageready_pending) + + /* Pairs with smp_store_mb() in kvm_set_msr_common(). */ + smp_mb__after_atomic(); + + if (!READ_ONCE(vcpu->arch.apf.pageready_pending)) kvm_vcpu_kick(vcpu); } diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index f3dc77f006f9..fdab0ad49098 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -420,6 +420,20 @@ static inline bool kvm_check_has_quirk(struct kvm *kvm, u64 quirk) return !(kvm->arch.disabled_quirks & quirk); } +static __always_inline void kvm_request_l1tf_flush_l1d(void) +{ +#if IS_ENABLED(CONFIG_CPU_MITIGATIONS) && IS_ENABLED(CONFIG_KVM_INTEL) + /* + * Use a raw write to set the per-CPU flag, as KVM will ensure a flush + * even if preemption is currently enabled.. If the current vCPU task + * is migrated to a different CPU (or userspace runs the vCPU on a + * different task) before the next VM-Entry, then kvm_arch_vcpu_load() + * will request a flush on the new CPU. + */ + raw_cpu_write(irq_stat.kvm_cpu_l1tf_flush_l1d, 1); +#endif +} + void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip); u64 get_kvmclock_ns(struct kvm *kvm); @@ -622,8 +636,6 @@ static inline void kvm_machine_check(void) #endif } -void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu); -void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu); int kvm_spec_ctrl_test_value(u64 value); int kvm_handle_memory_failure(struct kvm_vcpu *vcpu, int r, struct x86_exception *e); |