diff options
| author | Uros Bizjak <ubizjak@gmail.com> | 2018-10-17 16:46:57 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2018-10-17 19:08:21 +0200 |
| commit | 43ce76ce731ff7f9cff51124fee738018c18a864 (patch) | |
| tree | 9652072a1aaf6821cf8d60ee1081e401844c81a4 | |
| parent | kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD (diff) | |
| download | linux-43ce76ce731ff7f9cff51124fee738018c18a864.tar.xz linux-43ce76ce731ff7f9cff51124fee738018c18a864.zip | |
KVM/x86: Use 32bit xor to clear registers in svm.c
x86_64 zero-extends 32bit xor operation to a full 64bit register.
Also add a comment and remove unnecessary instruction suffix in vmx.c
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/svm.c | 28 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx.c | 6 |
2 files changed, 18 insertions, 16 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 1086bebaeea3..f416f5c7f2ae 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -5637,26 +5637,24 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu) "mov %%r13, %c[r13](%[svm]) \n\t" "mov %%r14, %c[r14](%[svm]) \n\t" "mov %%r15, %c[r15](%[svm]) \n\t" -#endif /* * Clear host registers marked as clobbered to prevent * speculative use. */ - "xor %%" _ASM_BX ", %%" _ASM_BX " \n\t" - "xor %%" _ASM_CX ", %%" _ASM_CX " \n\t" - "xor %%" _ASM_DX ", %%" _ASM_DX " \n\t" - "xor %%" _ASM_SI ", %%" _ASM_SI " \n\t" - "xor %%" _ASM_DI ", %%" _ASM_DI " \n\t" -#ifdef CONFIG_X86_64 - "xor %%r8, %%r8 \n\t" - "xor %%r9, %%r9 \n\t" - "xor %%r10, %%r10 \n\t" - "xor %%r11, %%r11 \n\t" - "xor %%r12, %%r12 \n\t" - "xor %%r13, %%r13 \n\t" - "xor %%r14, %%r14 \n\t" - "xor %%r15, %%r15 \n\t" + "xor %%r8d, %%r8d \n\t" + "xor %%r9d, %%r9d \n\t" + "xor %%r10d, %%r10d \n\t" + "xor %%r11d, %%r11d \n\t" + "xor %%r12d, %%r12d \n\t" + "xor %%r13d, %%r13d \n\t" + "xor %%r14d, %%r14d \n\t" + "xor %%r15d, %%r15d \n\t" #endif + "xor %%ebx, %%ebx \n\t" + "xor %%ecx, %%ecx \n\t" + "xor %%edx, %%edx \n\t" + "xor %%esi, %%esi \n\t" + "xor %%edi, %%edi \n\t" "pop %%" _ASM_BP : : [svm]"a"(svm), diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 91f4f5288150..3677609145a4 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -62,7 +62,7 @@ #define __ex(x) __kvm_handle_fault_on_reboot(x) #define __ex_clear(x, reg) \ - ____kvm_handle_fault_on_reboot(x, "xorl " reg " , " reg) + ____kvm_handle_fault_on_reboot(x, "xor " reg ", " reg) MODULE_AUTHOR("Qumranet"); MODULE_LICENSE("GPL"); @@ -11285,6 +11285,10 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu) "mov %%r13, %c[r13](%0) \n\t" "mov %%r14, %c[r14](%0) \n\t" "mov %%r15, %c[r15](%0) \n\t" + /* + * Clear host registers marked as clobbered to prevent + * speculative use. + */ "xor %%r8d, %%r8d \n\t" "xor %%r9d, %%r9d \n\t" "xor %%r10d, %%r10d \n\t" |