...to prepare for making the assembly sub-routine callable from C code.
Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
---
arch/x86/kvm/vmx/vmenter.S | 16 ++++++++--------
arch/x86/kvm/vmx/vmx.c | 8 ++++----
2 files changed, 12 insertions(+), 12 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmenter.S b/arch/x86/kvm/vmx/vmenter.S
index 3299fafbaa9b..246404b38b37 100644
--- a/arch/x86/kvm/vmx/vmenter.S
+++ b/arch/x86/kvm/vmx/vmenter.S
@@ -90,7 +90,7 @@ ENDPROC(vmx_vmexit)
* @launched: %true if the VMCS has been launched
*
* Returns:
- * %RBX is 0 on VM-Exit, 1 on VM-Fail
+ * 0 on VM-Exit, 1 on VM-Fail
*/
ENTRY(__vmx_vcpu_run)
push %_ASM_BP
@@ -166,17 +166,17 @@ ENTRY(__vmx_vcpu_run)
mov %r15, VCPU_R15(%_ASM_AX)
#endif
- /* Clear EBX to indicate VM-Exit (as opposed to VM-Fail). */
- xor %ebx, %ebx
+ /* Clear RAX to indicate VM-Exit (as opposed to VM-Fail). */
+ xor %eax, %eax
/*
- * Clear all general purpose registers except RSP and RBX to prevent
+ * Clear all general purpose registers except RSP and RAX to prevent
* speculative use of the guest's values, even those that are reloaded
* via the stack. In theory, an L1 cache miss when restoring registers
* could lead to speculative execution with the guest's values.
* Zeroing XORs are dirt cheap, i.e. the extra paranoia is essentially
- * free. RSP and RBX are exempt as RSP is restored by hardware during
- * VM-Exit and RBX is explicitly loaded with 0 or 1 to "return" VM-Fail.
+ * free. RSP and RAX are exempt as RSP is restored by hardware during
+ * VM-Exit and RAX is explicitly loaded with 0 or 1 to return VM-Fail.
*/
1:
#ifdef CONFIG_X86_64
@@ -189,7 +189,7 @@ ENTRY(__vmx_vcpu_run)
xor %r14d, %r14d
xor %r15d, %r15d
#endif
- xor %eax, %eax
+ xor %ebx, %ebx
xor %ecx, %ecx
xor %edx, %edx
xor %esi, %esi
@@ -202,6 +202,6 @@ ENTRY(__vmx_vcpu_run)
ret
/* VM-Fail. Out-of-line to avoid a taken Jcc after VM-Exit. */
-2: mov $1, %ebx
+2: mov $1, %eax
jmp 1b
ENDPROC(__vmx_vcpu_run)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 70e9b1820cc9..73a1e656b123 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6445,20 +6445,20 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
asm(
"call __vmx_vcpu_run \n\t"
- : ASM_CALL_CONSTRAINT, "=b"(vmx->fail),
+ : ASM_CALL_CONSTRAINT, "=a"(vmx->fail),
#ifdef CONFIG_X86_64
"=D"((int){0}), "=S"((int){0}), "=d"((int){0})
: "D"(vmx), "S"(&vcpu->arch.regs), "d"(vmx->loaded_vmcs->launched)
#else
- "=a"((int){0}), "=d"((int){0}), "=c"((int){0})
+ "=d"((int){0}), "=c"((int){0})
: "a"(vmx), "d"(&vcpu->arch.regs), "c"(vmx->loaded_vmcs->launched)
#endif
: "cc", "memory"
#ifdef CONFIG_X86_64
- , "rax", "rcx"
+ , "rbx", "rcx"
, "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15"
#else
- , "edi", "esi"
+ , "ebx", "edi", "esi"
#endif
);
--
2.20.1
