Merge tag 'kvm-x86-misc-6.19' of https://github.com/kvm-x86/linux into HEAD

KVM x86 misc changes for 6.19:

 - 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.

 - 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.

 - Leave the user-return notifier used to restore MSRs registered when
   disabling virtualization, and instead pin kvm.ko.  Restoring host MSRs via
   IPI callback is either pointless (clean reboot) or dangerous (forced reboot)
   since KVM has no idea what code it's interrupting.

 - Use the checked version of {get,put}_user(), as Linus wants to kill them
   off, and they're measurably faster on modern CPUs due to the unchecked
   versions containing an LFENCE.

 - 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 NPT 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 fastpath as
   the only reason they were handled in the faspath was to paper of a bug in
   the core #MC code that has long since been fixed.

 - Add emulator support for AVX MOV instructions to play nice with emulated
   devices whose PCI BARs guest drivers like to access with large multi-byte
   instructions.

1 files changed, 10 insertions, 17 deletions

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 9d29b2e7e855..6ddeeb0b1604 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3442,13 +3442,8 @@ 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;
 }
 
@@ -4251,7 +4246,6 @@ 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 +4288,6 @@ 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 +4319,6 @@ 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);
@@ -4622,8 +4607,16 @@ 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)