[PATCH 5/7] KVM: SVM: adjust register allocation for __svm_vcpu_run

From: Paolo Bonzini
Date: Fri Oct 28 2022 - 19:09:07 EST


In preparation for moving SPEC_CTRL access to __svm_vcpu_run,
keep the pointer to the struct vcpu_svm in %rdi, which is not
used by rdmsr/wrmsr.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/svm/vmenter.S | 39 +++++++++++++++++++-------------------
1 file changed, 20 insertions(+), 19 deletions(-)

diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S
index 8fac744361e5..51a63a47d74f 100644
--- a/arch/x86/kvm/svm/vmenter.S
+++ b/arch/x86/kvm/svm/vmenter.S
@@ -53,30 +53,31 @@ SYM_FUNC_START(__svm_vcpu_run)
/* Save @vmcb. */
push %_ASM_ARG1

- /* Move @svm to RAX. */
- mov %_ASM_ARG2, %_ASM_AX
+ /* Move @svm to RDI. */
+ mov %_ASM_ARG2, %_ASM_DI

- /* Load guest registers. */
- mov VCPU_RCX(%_ASM_AX), %_ASM_CX
- mov VCPU_RDX(%_ASM_AX), %_ASM_DX
- mov VCPU_RBX(%_ASM_AX), %_ASM_BX
- mov VCPU_RBP(%_ASM_AX), %_ASM_BP
- mov VCPU_RSI(%_ASM_AX), %_ASM_SI
- mov VCPU_RDI(%_ASM_AX), %_ASM_DI
-#ifdef CONFIG_X86_64
- mov VCPU_R8 (%_ASM_AX), %r8
- mov VCPU_R9 (%_ASM_AX), %r9
- mov VCPU_R10(%_ASM_AX), %r10
- mov VCPU_R11(%_ASM_AX), %r11
- mov VCPU_R12(%_ASM_AX), %r12
- mov VCPU_R13(%_ASM_AX), %r13
- mov VCPU_R14(%_ASM_AX), %r14
- mov VCPU_R15(%_ASM_AX), %r15
-#endif

/* "POP" @vmcb to RAX. */
pop %_ASM_AX

+ /* Load guest registers. */
+ mov VCPU_RCX(%_ASM_DI), %_ASM_CX
+ mov VCPU_RDX(%_ASM_DI), %_ASM_DX
+ mov VCPU_RBX(%_ASM_DI), %_ASM_BX
+ mov VCPU_RBP(%_ASM_DI), %_ASM_BP
+ mov VCPU_RSI(%_ASM_DI), %_ASM_SI
+#ifdef CONFIG_X86_64
+ mov VCPU_R8 (%_ASM_DI), %r8
+ mov VCPU_R9 (%_ASM_DI), %r9
+ mov VCPU_R10(%_ASM_DI), %r10
+ mov VCPU_R11(%_ASM_DI), %r11
+ mov VCPU_R12(%_ASM_DI), %r12
+ mov VCPU_R13(%_ASM_DI), %r13
+ mov VCPU_R14(%_ASM_DI), %r14
+ mov VCPU_R15(%_ASM_DI), %r15
+#endif
+ mov VCPU_RDI(%_ASM_DI), %_ASM_DI
+
/* Enter guest mode */
sti

--
2.31.1