From: Sean Christopherson sean.j.christopherson@intel.com
commit f3689e3f17f064fd4cd5f0cb01ae2395c94f39d9 upstream.
RSI is clobbered by the vCPU-run asm blob, but it's not marked as such, probably because GCC doesn't let you mark inputs as clobbered. "Save" RSI to a dummy output so that GCC recognizes it as being clobbered.
Fixes: 773e8a0425c9 ("x86/kvm: use Enlightened VMCS when running on Hyper-V") 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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kvm/vmx/vmx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6465,7 +6465,7 @@ static void __vmx_vcpu_run(struct kvm_vc "xor %%edi, %%edi \n\t" "xor %%ebp, %%ebp \n\t" "pop %%" _ASM_BP "; pop %%" _ASM_DX " \n\t" - : ASM_CALL_CONSTRAINT + : ASM_CALL_CONSTRAINT, "=S"((int){0}) : "c"(vmx), "d"((unsigned long)HOST_RSP), "S"(evmcs_rsp), [launched]"i"(offsetof(struct vcpu_vmx, __launched)), [fail]"i"(offsetof(struct vcpu_vmx, fail)),