diff options
Diffstat (limited to 'arch/x86/kernel/cpu/bugs.c')
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 22 |
1 files changed, 9 insertions, 13 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index d7fa03bf51b4..70bb48ab46d7 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -192,14 +192,6 @@ EXPORT_SYMBOL_GPL(cpu_buf_idle_clear); */ DEFINE_STATIC_KEY_FALSE(switch_mm_cond_l1d_flush); -/* - * Controls CPU Fill buffer clear before VMenter. This is a subset of - * X86_FEATURE_CLEAR_CPU_BUF, and should only be enabled when KVM-only - * mitigation is required. - */ -DEFINE_STATIC_KEY_FALSE(cpu_buf_vm_clear); -EXPORT_SYMBOL_GPL(cpu_buf_vm_clear); - #undef pr_fmt #define pr_fmt(fmt) "mitigations: " fmt @@ -489,8 +481,8 @@ static enum rfds_mitigations rfds_mitigation __ro_after_init = IS_ENABLED(CONFIG_MITIGATION_RFDS) ? RFDS_MITIGATION_AUTO : RFDS_MITIGATION_OFF; /* - * Set if any of MDS/TAA/MMIO/RFDS are going to enable VERW clearing - * through X86_FEATURE_CLEAR_CPU_BUF on kernel and guest entry. + * Set if any of MDS/TAA/MMIO/RFDS are going to enable VERW clearing on exit to + * userspace *and* on entry to KVM guests. */ static bool verw_clear_cpu_buf_mitigation_selected __ro_after_init; @@ -536,6 +528,7 @@ static void __init mds_apply_mitigation(void) if (mds_mitigation == MDS_MITIGATION_FULL || mds_mitigation == MDS_MITIGATION_VMWERV) { setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF); + setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF_VM); if (!boot_cpu_has(X86_BUG_MSBDS_ONLY) && (mds_nosmt || smt_mitigations == SMT_MITIGATIONS_ON)) cpu_smt_disable(false); @@ -647,6 +640,7 @@ static void __init taa_apply_mitigation(void) * present on host, enable the mitigation for UCODE_NEEDED as well. */ setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF); + setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF_VM); if (taa_nosmt || smt_mitigations == SMT_MITIGATIONS_ON) cpu_smt_disable(false); @@ -748,9 +742,9 @@ static void __init mmio_apply_mitigation(void) */ if (verw_clear_cpu_buf_mitigation_selected) { setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF); - static_branch_disable(&cpu_buf_vm_clear); + setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF_VM); } else { - static_branch_enable(&cpu_buf_vm_clear); + setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF_VM_MMIO); } /* @@ -839,8 +833,10 @@ static void __init rfds_update_mitigation(void) static void __init rfds_apply_mitigation(void) { - if (rfds_mitigation == RFDS_MITIGATION_VERW) + if (rfds_mitigation == RFDS_MITIGATION_VERW) { setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF); + setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF_VM); + } } static __init int rfds_parse_cmdline(char *str) |