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| author | Sean Christopherson <sean.j.christopherson@intel.com> | 2019-01-25 07:40:54 -0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-02-12 13:12:17 +0100 |
| commit | 6f7c6d23b71af2e65056e777eeb2f1e6e0195f14 (patch) | |
| tree | fb28ad96b14e55295a73ee52828af72abb1b8c15 | |
| parent | ccf447434ee624b64a1c215d88453f1921aaa88a (diff) | |
| download | linux-6f7c6d23b71af2e65056e777eeb2f1e6e0195f14.tar.bz2 | |
KVM: VMX: Let the compiler save/load RDX during vCPU-run
Per commit c20363006af6 ("KVM: VMX: Let gcc to choose which registers
to save (x86_64)"), the only reason RDX is saved/loaded to/from the
stack is because it was specified as an input, i.e. couldn't be marked
as clobbered (ignoring the fact that "saving" it to a dummy output
would indirectly mark it as clobbered).
Now that RDX is no longer an input, clobber it.
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index b935ba3306aa..e9d81cd8421f 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6377,7 +6377,7 @@ static void __vmx_vcpu_run(struct kvm_vcpu *vcpu, struct vcpu_vmx *vmx) asm( /* Store host registers */ - "push %%" _ASM_DX "; push %%" _ASM_BP ";" + "push %%" _ASM_BP " \n\t" "sub $%c[wordsize], %%" _ASM_SP "\n\t" /* placeholder for guest RCX */ "push %%" _ASM_CX " \n\t" "sub $%c[wordsize], %%" _ASM_SP "\n\t" /* temporarily adjust RSP for CALL */ @@ -6481,7 +6481,7 @@ static void __vmx_vcpu_run(struct kvm_vcpu *vcpu, struct vcpu_vmx *vmx) "xor %%esi, %%esi \n\t" "xor %%edi, %%edi \n\t" "xor %%ebp, %%ebp \n\t" - "pop %%" _ASM_BP "; pop %%" _ASM_DX " \n\t" + "pop %%" _ASM_BP " \n\t" : ASM_CALL_CONSTRAINT, "=S"((int){0}) : "c"(vmx), "S"(evmcs_rsp), [launched]"i"(offsetof(struct vcpu_vmx, __launched)), @@ -6509,10 +6509,10 @@ static void __vmx_vcpu_run(struct kvm_vcpu *vcpu, struct vcpu_vmx *vmx) [wordsize]"i"(sizeof(ulong)) : "cc", "memory" #ifdef CONFIG_X86_64 - , "rax", "rbx", "rdi" + , "rax", "rbx", "rdx", "rdi" , "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15" #else - , "eax", "ebx", "edi" + , "eax", "ebx", "edx", "edi" #endif ); } |