diff options
| author | Sean Christopherson <seanjc@google.com> | 2025-11-13 15:37:43 -0800 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2025-11-18 16:22:43 -0800 |
| commit | fc704b578976ed6a937f419e611d5ae92c939826 (patch) | |
| tree | 02c3cc35c823d22a0f1a3db087512b69f055a6e9 | |
| parent | e6ff1d61de51ec5fe94c5fb79544a93f494104eb (diff) | |
x86/bugs: KVM: Move VM_CLEAR_CPU_BUFFERS into SVM as SVM_CLEAR_CPU_BUFFERS
Now that VMX encodes its own sequence for clearing CPU buffers, move
VM_CLEAR_CPU_BUFFERS into SVM to minimize the chances of KVM botching a
mitigation in the future, e.g. using VM_CLEAR_CPU_BUFFERS instead of
checking multiple mitigation flags.
No functional change intended.
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20251113233746.1703361-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
| -rw-r--r-- | arch/x86/include/asm/nospec-branch.h | 3 | ||||
| -rw-r--r-- | arch/x86/kvm/svm/vmenter.S | 6 |
2 files changed, 4 insertions, 5 deletions
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index afdcdf40e414..a6526c5be5ca 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -329,9 +329,6 @@ #define CLEAR_CPU_BUFFERS \ ALTERNATIVE "", __CLEAR_CPU_BUFFERS, X86_FEATURE_CLEAR_CPU_BUF -#define VM_CLEAR_CPU_BUFFERS \ - ALTERNATIVE "", __CLEAR_CPU_BUFFERS, X86_FEATURE_CLEAR_CPU_BUF_VM - #ifdef CONFIG_X86_64 .macro CLEAR_BRANCH_HISTORY ALTERNATIVE "", "call clear_bhb_loop", X86_FEATURE_CLEAR_BHB_LOOP diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S index 235c4af6b692..da5f481cb17e 100644 --- a/arch/x86/kvm/svm/vmenter.S +++ b/arch/x86/kvm/svm/vmenter.S @@ -92,6 +92,8 @@ 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 @@ -170,7 +172,7 @@ 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 @@ -339,7 +341,7 @@ 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 |