[PATCH 7/8] KVM: SVM: Create a stack frame in __svm_sev_es_vcpu_run()

From: Sean Christopherson
Date: Fri Feb 23 2024 - 15:46:51 EST


Now that KVM uses the host save area to context switch RBP, i.e.
preserves RBP for the entirety of __svm_sev_es_vcpu_run(), create a stack
frame using the standared FRAME_{BEGIN,END} macros.

Note, __svm_sev_es_vcpu_run() is subtly not a leaf function as it can call
into ibpb_feature() via UNTRAIN_RET_VM.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/svm/vmenter.S | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S
index 48cdba47622c..5461c23ee762 100644
--- a/arch/x86/kvm/svm/vmenter.S
+++ b/arch/x86/kvm/svm/vmenter.S
@@ -3,6 +3,7 @@
#include <asm/asm.h>
#include <asm/asm-offsets.h>
#include <asm/bitsperlong.h>
+#include <asm/frame.h>
#include <asm/kvm_vcpu_regs.h>
#include <asm/nospec-branch.h>
#include "kvm-asm-offsets.h"
@@ -312,6 +313,8 @@ SYM_FUNC_END(__svm_vcpu_run)
* @spec_ctrl_intercepted: bool
*/
SYM_FUNC_START(__svm_sev_es_vcpu_run)
+ FRAME_BEGIN
+
/*
* Save non-volatile (callee-saved) registers to the host save area.
* Except for RAX and RSP, all GPRs are restored on #VMEXIT, but not
@@ -362,6 +365,7 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run)
*/
UNTRAIN_RET_VM

+ FRAME_END
RET

RESTORE_GUEST_SPEC_CTRL_BODY
--
2.44.0.rc0.258.g7320e95886-goog