On Wed, Jun 26, 2024, Amit Shah wrote: > --- > arch/x86/kvm/svm/vmenter.S | 8 ++------ > 1 file changed, 2 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S > index a0c8eb37d3e1..2ed80aea3bb1 100644 > --- a/arch/x86/kvm/svm/vmenter.S > +++ b/arch/x86/kvm/svm/vmenter.S > @@ -209,10 +209,8 @@ SYM_FUNC_START(__svm_vcpu_run) > 7: vmload %_ASM_AX > 8: > > -#ifdef CONFIG_MITIGATION_RETPOLINE > /* IMPORTANT: Stuff the RSB immediately after VM-Exit, before RET! */ > - FILL_RETURN_BUFFER %_ASM_AX, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE > -#endif > + FILL_RETURN_BUFFER %_ASM_AX, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_VMEXIT Out of an abundance of paranoia, shouldn't this be? FILL_RETURN_BUFFER %_ASM_CX, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_VMEXIT,\ X86_FEATURE_RSB_VMEXIT_LITE Hmm, but it looks like that would incorrectly trigger the "lite" flavor for families 0xf - 0x12. I assume those old CPUs aren't affected by whatever on earth EIBRS_PBRSB is. /* AMD Family 0xf - 0x12 */ VULNWL_AMD(0x0f, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_BHI), VULNWL_AMD(0x10, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_BHI), VULNWL_AMD(0x11, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_BHI), VULNWL_AMD(0x12, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_BHI), /* FAMILY_ANY must be last, otherwise 0x0f - 0x12 matches won't work */ VULNWL_AMD(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_EIBRS_PBRSB | NO_BHI), VULNWL_HYGON(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_EIBRS_PBRSB | NO_BHI), > > /* Clobbers RAX, RCX, RDX. */ > RESTORE_HOST_SPEC_CTRL > @@ -348,10 +346,8 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run) > > 2: cli > > -#ifdef CONFIG_MITIGATION_RETPOLINE > /* IMPORTANT: Stuff the RSB immediately after VM-Exit, before RET! */ > - FILL_RETURN_BUFFER %rax, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE > -#endif > + FILL_RETURN_BUFFER %rax, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_VMEXIT > > /* Clobbers RAX, RCX, RDX, consumes RDI (@svm) and RSI (@spec_ctrl_intercepted). */ > RESTORE_HOST_SPEC_CTRL > -- > 2.45.2 >
