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* [PATCH 0/3] KVM: Macrofy GPR swapping in assembly code
@ 2026-05-13 17:49 Paolo Bonzini
  2026-05-13 17:49 ` [PATCH 1/3] KVM: VMX: Macrofy GPR swapping in __vmx_vcpu_run() Paolo Bonzini
                   ` (2 more replies)
  0 siblings, 3 replies; 5+ messages in thread
From: Paolo Bonzini @ 2026-05-13 17:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: chang.seok.bae

A small change to Chang's patches from the APX series.
The only change is keeping __VCPU_REGS_* constants to avoid
relying on the ordering of constants in kvm_host.h.

While the kvm_vcpu_regs.h changes make the line count boom a bit,
the actual assembly code loses almost a hundred lines and
APX makes that even more extreme.

Paolo

Chang S. Bae (3):
  KVM: VMX: Macrofy GPR swapping in __vmx_vcpu_run()
  KVM: SVM: Macrofy GPR swapping in __svm_vcpu_run()
  KVM: SEV: Macrofy GPR swapping in __svm_sev_es_vcpu_run()

 arch/x86/include/asm/kvm_host.h      |  16 ++--
 arch/x86/include/asm/kvm_vcpu_regs.h | 127 +++++++++++++++++++++++++--
 arch/x86/kvm/svm/vmenter.S           | 107 +++++-----------------
 arch/x86/kvm/vmenter.h               |  43 +++++++++
 arch/x86/kvm/vmx/vmenter.S           |  89 +++++--------------
 5 files changed, 211 insertions(+), 171 deletions(-)

-- 
2.52.0


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH 1/3] KVM: VMX: Macrofy GPR swapping in __vmx_vcpu_run()
  2026-05-13 17:49 [PATCH 0/3] KVM: Macrofy GPR swapping in assembly code Paolo Bonzini
@ 2026-05-13 17:49 ` Paolo Bonzini
  2026-05-14 19:30   ` Sean Christopherson
  2026-05-13 17:49 ` [PATCH 2/3] KVM: SVM: Macrofy GPR swapping in __svm_vcpu_run() Paolo Bonzini
  2026-05-13 17:49 ` [PATCH 3/3] KVM: SEV: Macrofy GPR swapping in __svm_sev_es_vcpu_run() Paolo Bonzini
  2 siblings, 1 reply; 5+ messages in thread
From: Paolo Bonzini @ 2026-05-13 17:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: chang.seok.bae, x86

From: "Chang S. Bae" <chang.seok.bae@intel.com>

Convert the repeated register save/restore sequences into macros to
simplify the VM entry code. This can also make it easier to extend for
additional registers.

No functional change intended.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: x86@kernel.org
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Link: https://lore.kernel.org/6e67df0e-e5f0-43f5-aa86-22e8b01b75d2@redhat.com
Message-ID: <20260512011502.53072-2-chang.seok.bae@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/kvm_vcpu_regs.h | 122 +++++++++++++++++++++++++++
 arch/x86/kvm/svm/vmenter.S           |   3 -
 arch/x86/kvm/vmenter.h               |  43 ++++++++++
 arch/x86/kvm/vmx/vmenter.S           |  89 +++++--------------
 4 files changed, 185 insertions(+), 72 deletions(-)

diff --git a/arch/x86/include/asm/kvm_vcpu_regs.h b/arch/x86/include/asm/kvm_vcpu_regs.h
index 1af2cb59233b..7c12a1fd1ffc 100644
--- a/arch/x86/include/asm/kvm_vcpu_regs.h
+++ b/arch/x86/include/asm/kvm_vcpu_regs.h
@@ -22,4 +22,126 @@
 #define __VCPU_REGS_R15 15
 #endif
 
+#ifdef __ASSEMBLER__
+
+#define REG_NUM_INVALID		100
+
+	.macro R32_NUM opd r32
+	\opd = REG_NUM_INVALID
+	.ifc \r32,%eax
+	\opd = __VCPU_REGS_EAX
+	.endif
+	.ifc \r32,%ecx
+	\opd = __VCPU_REGS_ECX
+	.endif
+	.ifc \r32,%edx
+	\opd = __VCPU_REGS_EDX
+	.endif
+	.ifc \r32,%ebx
+	\opd = __VCPU_REGS_EBX
+	.endif
+	.ifc \r32,%esp
+	\opd = __VCPU_REGS_ESP
+	.endif
+	.ifc \r32,%ebp
+	\opd = __VCPU_REGS_EBP
+	.endif
+	.ifc \r32,%esi
+	\opd = __VCPU_REGS_ESI
+	.endif
+	.ifc \r32,%edi
+	\opd = __VCPU_REGS_EDI
+	.endif
+#ifdef CONFIG_X86_64
+	.ifc \r32,%r8d
+	\opd = 8
+	.endif
+	.ifc \r32,%r9d
+	\opd = 9
+	.endif
+	.ifc \r32,%r10d
+	\opd = 10
+	.endif
+	.ifc \r32,%r11d
+	\opd = 11
+	.endif
+	.ifc \r32,%r12d
+	\opd = 12
+	.endif
+	.ifc \r32,%r13d
+	\opd = 13
+	.endif
+	.ifc \r32,%r14d
+	\opd = 14
+	.endif
+	.ifc \r32,%r15d
+	\opd = 15
+	.endif
+#endif
+	.endm
+
+	.macro R64_NUM opd r64
+	\opd = REG_NUM_INVALID
+#ifdef CONFIG_X86_64
+	.ifc \r64,%rax
+	\opd = __VCPU_REGS_RAX
+	.endif
+	.ifc \r64,%rcx
+	\opd = __VCPU_REGS_RCX
+	.endif
+	.ifc \r64,%rdx
+	\opd = __VCPU_REGS_RDX
+	.endif
+	.ifc \r64,%rbx
+	\opd = __VCPU_REGS_RBX
+	.endif
+	.ifc \r64,%rsp
+	\opd = __VCPU_REGS_RSP
+	.endif
+	.ifc \r64,%rbp
+	\opd = __VCPU_REGS_RBP
+	.endif
+	.ifc \r64,%rsi
+	\opd = __VCPU_REGS_RSI
+	.endif
+	.ifc \r64,%rdi
+	\opd = __VCPU_REGS_RDI
+	.endif
+	.ifc \r64,%r8
+	\opd = 8
+	.endif
+	.ifc \r64,%r9
+	\opd = 9
+	.endif
+	.ifc \r64,%r10
+	\opd = 10
+	.endif
+	.ifc \r64,%r11
+	\opd = 11
+	.endif
+	.ifc \r64,%r12
+	\opd = 12
+	.endif
+	.ifc \r64,%r13
+	\opd = 13
+	.endif
+	.ifc \r64,%r14
+	\opd = 14
+	.endif
+	.ifc \r64,%r15
+	\opd = 15
+	.endif
+#endif
+	.endm
+
+.macro REG_NUM reg_num reg
+#ifdef CONFIG_X86_64
+	R64_NUM \reg_num \reg
+#else
+	R32_NUM \reg_num \reg
+#endif
+.endm
+
+#endif
+
 #endif /* _ASM_X86_KVM_VCPU_REGS_H */
diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S
index f523d9e49839..6a91e1383e8f 100644
--- a/arch/x86/kvm/svm/vmenter.S
+++ b/arch/x86/kvm/svm/vmenter.S
@@ -4,13 +4,10 @@
 #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"
 #include "vmenter.h"
 
-#define WORD_SIZE (BITS_PER_LONG / 8)
-
 /* Intentionally omit RAX as it's context switched by hardware */
 #define VCPU_RCX	(SVM_vcpu_arch_regs + __VCPU_REGS_RCX * WORD_SIZE)
 #define VCPU_RDX	(SVM_vcpu_arch_regs + __VCPU_REGS_RDX * WORD_SIZE)
diff --git a/arch/x86/kvm/vmenter.h b/arch/x86/kvm/vmenter.h
index ba3f71449c62..44574806cb02 100644
--- a/arch/x86/kvm/vmenter.h
+++ b/arch/x86/kvm/vmenter.h
@@ -2,6 +2,8 @@
 #ifndef __KVM_X86_VMENTER_H
 #define __KVM_X86_VMENTER_H
 
+#include <asm/kvm_vcpu_regs.h>
+
 #define KVM_ENTER_VMRESUME			BIT(0)
 #define KVM_ENTER_SAVE_SPEC_CTRL		BIT(1)
 #define KVM_ENTER_CLEAR_CPU_BUFFERS_FOR_MMIO	BIT(2)
@@ -76,5 +78,46 @@
 	wrmsr
 .endm
 
+#define WORD_SIZE (BITS_PER_LONG / 8)
+
+.macro LOAD_REGS src:req, regs_ofs:req, regs:vararg
+.irp reg, \regs
+	REG_NUM reg_num \reg
+	.if reg_num <> REG_NUM_INVALID
+	mov (\regs_ofs + reg_num * WORD_SIZE)(\src), \reg
+	.else
+	.err invalid register \reg
+	.endif
+.endr
+.endm
+
+.macro STORE_REGS dst:req, regs_ofs:req, regs:vararg
+.irp reg, \regs
+	REG_NUM reg_num \reg
+	.if reg_num <> REG_NUM_INVALID
+	mov \reg, (\regs_ofs + reg_num * WORD_SIZE)(\dst)
+	.else
+	.err invalid register \reg
+	.endif
+.endr
+.endm
+
+.macro POP_REGS dst:req, regs_ofs:req, regs:vararg
+.irp reg, \regs
+	REG_NUM reg_num \reg
+	.if reg_num <> REG_NUM_INVALID
+	pop (\regs_ofs + reg_num * WORD_SIZE)(\dst)
+	.else
+	.err invalid register \reg
+	.endif
+.endr
+.endm
+
+.macro CLEAR_REGS regs:vararg
+.irp reg, \regs
+	xorl \reg, \reg
+.endr
+.endm
+
 #endif /* __ASSEMBLER__ */
 #endif /* __KVM_X86_VMENTER_H */
diff --git a/arch/x86/kvm/vmx/vmenter.S b/arch/x86/kvm/vmx/vmenter.S
index 7e4dc17fc0b8..4b7aaa7430fb 100644
--- a/arch/x86/kvm/vmx/vmenter.S
+++ b/arch/x86/kvm/vmx/vmenter.S
@@ -2,35 +2,12 @@
 #include <linux/linkage.h>
 #include <asm/asm.h>
 #include <asm/bitsperlong.h>
-#include <asm/kvm_vcpu_regs.h>
 #include <asm/nospec-branch.h>
 #include <asm/percpu.h>
 #include <asm/segment.h>
 #include "kvm-asm-offsets.h"
 #include "vmenter.h"
 
-#define WORD_SIZE (BITS_PER_LONG / 8)
-
-#define VCPU_RAX	(VMX_vcpu_arch_regs + __VCPU_REGS_RAX * WORD_SIZE)
-#define VCPU_RCX	(VMX_vcpu_arch_regs + __VCPU_REGS_RCX * WORD_SIZE)
-#define VCPU_RDX	(VMX_vcpu_arch_regs + __VCPU_REGS_RDX * WORD_SIZE)
-#define VCPU_RBX	(VMX_vcpu_arch_regs + __VCPU_REGS_RBX * WORD_SIZE)
-/* Intentionally omit RSP as it's context switched by hardware */
-#define VCPU_RBP	(VMX_vcpu_arch_regs + __VCPU_REGS_RBP * WORD_SIZE)
-#define VCPU_RSI	(VMX_vcpu_arch_regs + __VCPU_REGS_RSI * WORD_SIZE)
-#define VCPU_RDI	(VMX_vcpu_arch_regs + __VCPU_REGS_RDI * WORD_SIZE)
-
-#ifdef CONFIG_X86_64
-#define VCPU_R8		(VMX_vcpu_arch_regs + __VCPU_REGS_R8  * WORD_SIZE)
-#define VCPU_R9		(VMX_vcpu_arch_regs + __VCPU_REGS_R9  * WORD_SIZE)
-#define VCPU_R10	(VMX_vcpu_arch_regs + __VCPU_REGS_R10 * WORD_SIZE)
-#define VCPU_R11	(VMX_vcpu_arch_regs + __VCPU_REGS_R11 * WORD_SIZE)
-#define VCPU_R12	(VMX_vcpu_arch_regs + __VCPU_REGS_R12 * WORD_SIZE)
-#define VCPU_R13	(VMX_vcpu_arch_regs + __VCPU_REGS_R13 * WORD_SIZE)
-#define VCPU_R14	(VMX_vcpu_arch_regs + __VCPU_REGS_R14 * WORD_SIZE)
-#define VCPU_R15	(VMX_vcpu_arch_regs + __VCPU_REGS_R15 * WORD_SIZE)
-#endif
-
 .macro VMX_DO_EVENT_IRQOFF call_insn call_target
 	/*
 	 * Unconditionally create a stack frame, getting the correct RSP on the
@@ -114,25 +91,18 @@ SYM_FUNC_START(__vmx_vcpu_run)
 	 * an LFENCE to stop speculation from skipping the wrmsr.
 	 */
 
-	/* Load guest registers.  Don't clobber flags. */
-	mov VCPU_RAX(%_ASM_DI), %_ASM_AX
-	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
+	/*
+	 * Load guest registers.  Don't clobber flags. Intentionally omit
+	 * %_ASM_SP as it's context switched by hardware
+	 */
+	LOAD_REGS %_ASM_DI, VMX_vcpu_arch_regs, \
+		  %_ASM_AX, %_ASM_CX, %_ASM_DX, %_ASM_BX, %_ASM_BP, %_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
+	LOAD_REGS %_ASM_DI, VMX_vcpu_arch_regs, \
+		  %r8, %r9, %r10, %r11, %r12, %r13, %r14, %r15
 #endif
 	/* Load guest RDI.  This kills the @vmx pointer! */
-	mov VCPU_RDI(%_ASM_DI), %_ASM_DI
+	LOAD_REGS %_ASM_DI, VMX_vcpu_arch_regs, %_ASM_DI
 
 	/*
 	 * Note, ALTERNATIVE_2 works in reverse order.  If CLEAR_CPU_BUF_VM is
@@ -187,23 +157,16 @@ SYM_INNER_LABEL_ALIGN(vmx_vmexit, SYM_L_GLOBAL)
 	/* Reload @vmx to RDI. */
 	mov 2*WORD_SIZE(%_ASM_SP), %_ASM_DI
 
-	/* Save all guest registers, including RDI from the stack */
-	mov %_ASM_AX, VCPU_RAX(%_ASM_DI)
-	mov %_ASM_CX, VCPU_RCX(%_ASM_DI)
-	mov %_ASM_DX, VCPU_RDX(%_ASM_DI)
-	mov %_ASM_BX, VCPU_RBX(%_ASM_DI)
-	mov %_ASM_BP, VCPU_RBP(%_ASM_DI)
-	mov %_ASM_SI, VCPU_RSI(%_ASM_DI)
-	pop           VCPU_RDI(%_ASM_DI)
+	/*
+	 * Save all guest registers, including RDI from the stack. Intentionally
+	 * omit %_ASM_SP as it's context switched by hardware
+	 */
+	STORE_REGS %_ASM_DI, VMX_vcpu_arch_regs, \
+		   %_ASM_AX, %_ASM_CX, %_ASM_DX, %_ASM_BX, %_ASM_BP, %_ASM_SI
+	POP_REGS   %_ASM_DI, VMX_vcpu_arch_regs, %_ASM_DI
 #ifdef CONFIG_X86_64
-	mov %r8,  VCPU_R8 (%_ASM_DI)
-	mov %r9,  VCPU_R9 (%_ASM_DI)
-	mov %r10, VCPU_R10(%_ASM_DI)
-	mov %r11, VCPU_R11(%_ASM_DI)
-	mov %r12, VCPU_R12(%_ASM_DI)
-	mov %r13, VCPU_R13(%_ASM_DI)
-	mov %r14, VCPU_R14(%_ASM_DI)
-	mov %r15, VCPU_R15(%_ASM_DI)
+	STORE_REGS %_ASM_DI, VMX_vcpu_arch_regs, \
+		   %r8, %r9, %r10, %r11, %r12, %r13, %r14, %r15
 #endif
 
 	/* Clear return value to indicate VM-Exit (as opposed to VM-Fail). */
@@ -220,21 +183,9 @@ SYM_INNER_LABEL_ALIGN(vmx_vmexit, SYM_L_GLOBAL)
 	 * VM-Exit and RBX is explicitly loaded with 0 or 1 to hold the return
 	 * value.
 	 */
-	xor %eax, %eax
-	xor %ecx, %ecx
-	xor %edx, %edx
-	xor %ebp, %ebp
-	xor %esi, %esi
-	xor %edi, %edi
+	CLEAR_REGS %eax, %ecx, %edx, %ebp, %esi, %edi
 #ifdef CONFIG_X86_64
-	xor %r8d,  %r8d
-	xor %r9d,  %r9d
-	xor %r10d, %r10d
-	xor %r11d, %r11d
-	xor %r12d, %r12d
-	xor %r13d, %r13d
-	xor %r14d, %r14d
-	xor %r15d, %r15d
+	CLEAR_REGS %r8d, %r9d, %r10d, %r11d, %r12d, %r13d, %r14d, %r15d
 #endif
 
 	/*
-- 
2.52.0



^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 2/3] KVM: SVM: Macrofy GPR swapping in __svm_vcpu_run()
  2026-05-13 17:49 [PATCH 0/3] KVM: Macrofy GPR swapping in assembly code Paolo Bonzini
  2026-05-13 17:49 ` [PATCH 1/3] KVM: VMX: Macrofy GPR swapping in __vmx_vcpu_run() Paolo Bonzini
@ 2026-05-13 17:49 ` Paolo Bonzini
  2026-05-13 17:49 ` [PATCH 3/3] KVM: SEV: Macrofy GPR swapping in __svm_sev_es_vcpu_run() Paolo Bonzini
  2 siblings, 0 replies; 5+ messages in thread
From: Paolo Bonzini @ 2026-05-13 17:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: chang.seok.bae

From: "Chang S. Bae" <chang.seok.bae@intel.com>

Convert the register save/restore sequences in the SVM entry into macros,
following the VMX code. Drop the now-redundant register offset defines.

No functional change intended.

Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Message-ID: <20260512011502.53072-3-chang.seok.bae@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/svm/vmenter.S | 83 +++++++++-----------------------------
 1 file changed, 19 insertions(+), 64 deletions(-)

diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S
index 6a91e1383e8f..06a8cb58f187 100644
--- a/arch/x86/kvm/svm/vmenter.S
+++ b/arch/x86/kvm/svm/vmenter.S
@@ -8,26 +8,6 @@
 #include "kvm-asm-offsets.h"
 #include "vmenter.h"
 
-/* Intentionally omit RAX as it's context switched by hardware */
-#define VCPU_RCX	(SVM_vcpu_arch_regs + __VCPU_REGS_RCX * WORD_SIZE)
-#define VCPU_RDX	(SVM_vcpu_arch_regs + __VCPU_REGS_RDX * WORD_SIZE)
-#define VCPU_RBX	(SVM_vcpu_arch_regs + __VCPU_REGS_RBX * WORD_SIZE)
-/* Intentionally omit RSP as it's context switched by hardware */
-#define VCPU_RBP	(SVM_vcpu_arch_regs + __VCPU_REGS_RBP * WORD_SIZE)
-#define VCPU_RSI	(SVM_vcpu_arch_regs + __VCPU_REGS_RSI * WORD_SIZE)
-#define VCPU_RDI	(SVM_vcpu_arch_regs + __VCPU_REGS_RDI * WORD_SIZE)
-
-#ifdef CONFIG_X86_64
-#define VCPU_R8		(SVM_vcpu_arch_regs + __VCPU_REGS_R8  * WORD_SIZE)
-#define VCPU_R9		(SVM_vcpu_arch_regs + __VCPU_REGS_R9  * WORD_SIZE)
-#define VCPU_R10	(SVM_vcpu_arch_regs + __VCPU_REGS_R10 * WORD_SIZE)
-#define VCPU_R11	(SVM_vcpu_arch_regs + __VCPU_REGS_R11 * WORD_SIZE)
-#define VCPU_R12	(SVM_vcpu_arch_regs + __VCPU_REGS_R12 * WORD_SIZE)
-#define VCPU_R13	(SVM_vcpu_arch_regs + __VCPU_REGS_R13 * WORD_SIZE)
-#define VCPU_R14	(SVM_vcpu_arch_regs + __VCPU_REGS_R14 * WORD_SIZE)
-#define VCPU_R15	(SVM_vcpu_arch_regs + __VCPU_REGS_R15 * WORD_SIZE)
-#endif
-
 #define SVM_vmcb01_pa	(SVM_vmcb01 + KVM_VMCB_pa)
 
 .section .noinstr.text, "ax"
@@ -108,23 +88,17 @@ SYM_FUNC_START(__svm_vcpu_run)
 	mov SVM_current_vmcb(%_ASM_DI), %_ASM_AX
 	mov KVM_VMCB_pa(%_ASM_AX), %_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
+	/*
+	 * Load guest registers. Intentionally omit %_ASM_AX and %_ASM_SP as
+	 * context switched by hardware
+	 */
+	LOAD_REGS %_ASM_DI, SVM_vcpu_arch_regs, \
+		  %_ASM_CX, %_ASM_DX, %_ASM_BX, %_ASM_BP, %_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
+	LOAD_REGS %_ASM_DI, SVM_vcpu_arch_regs, \
+		  %r8, %r9, %r10, %r11, %r12, %r13, %r14, %r15
 #endif
-	mov VCPU_RDI(%_ASM_DI), %_ASM_DI
+	LOAD_REGS %_ASM_DI, SVM_vcpu_arch_regs, %_ASM_DI
 
 	/* Clobbers EFLAGS.ZF */
 	SVM_CLEAR_CPU_BUFFERS
@@ -135,22 +109,15 @@ SYM_FUNC_START(__svm_vcpu_run)
 	/* Pop @svm to RAX while it's the only available register. */
 	pop %_ASM_AX
 
-	/* Save all guest registers.  */
-	mov %_ASM_CX,   VCPU_RCX(%_ASM_AX)
-	mov %_ASM_DX,   VCPU_RDX(%_ASM_AX)
-	mov %_ASM_BX,   VCPU_RBX(%_ASM_AX)
-	mov %_ASM_BP,   VCPU_RBP(%_ASM_AX)
-	mov %_ASM_SI,   VCPU_RSI(%_ASM_AX)
-	mov %_ASM_DI,   VCPU_RDI(%_ASM_AX)
+	/*
+	 * Save all guest registers. Intentionally omit %_ASM_AX and %_ASM_SP as
+	 * context switched by hardware
+	 */
+	STORE_REGS %_ASM_AX, SVM_vcpu_arch_regs, \
+		   %_ASM_CX, %_ASM_DX, %_ASM_BX, %_ASM_BP, %_ASM_SI, %_ASM_DI
 #ifdef CONFIG_X86_64
-	mov %r8,  VCPU_R8 (%_ASM_AX)
-	mov %r9,  VCPU_R9 (%_ASM_AX)
-	mov %r10, VCPU_R10(%_ASM_AX)
-	mov %r11, VCPU_R11(%_ASM_AX)
-	mov %r12, VCPU_R12(%_ASM_AX)
-	mov %r13, VCPU_R13(%_ASM_AX)
-	mov %r14, VCPU_R14(%_ASM_AX)
-	mov %r15, VCPU_R15(%_ASM_AX)
+	STORE_REGS %_ASM_AX, SVM_vcpu_arch_regs, \
+		   %r8, %r9, %r10, %r11, %r12, %r13, %r14, %r15
 #endif
 
 	/* @svm can stay in RDI from now on.  */
@@ -193,21 +160,9 @@ SYM_FUNC_START(__svm_vcpu_run)
 	 * free.  RSP and RAX are exempt as they are restored by hardware
 	 * during VM-Exit.
 	 */
-	xor %ecx, %ecx
-	xor %edx, %edx
-	xor %ebx, %ebx
-	xor %ebp, %ebp
-	xor %esi, %esi
-	xor %edi, %edi
+	CLEAR_REGS %ecx, %edx, %ebx, %ebp, %esi, %edi
 #ifdef CONFIG_X86_64
-	xor %r8d,  %r8d
-	xor %r9d,  %r9d
-	xor %r10d, %r10d
-	xor %r11d, %r11d
-	xor %r12d, %r12d
-	xor %r13d, %r13d
-	xor %r14d, %r14d
-	xor %r15d, %r15d
+	CLEAR_REGS %r8d, %r9d, %r10d, %r11d, %r12d, %r13d, %r14d, %r15d
 #endif
 
 	/* "Pop" @enter_flags.  */
-- 
2.52.0



^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 3/3] KVM: SEV: Macrofy GPR swapping in __svm_sev_es_vcpu_run()
  2026-05-13 17:49 [PATCH 0/3] KVM: Macrofy GPR swapping in assembly code Paolo Bonzini
  2026-05-13 17:49 ` [PATCH 1/3] KVM: VMX: Macrofy GPR swapping in __vmx_vcpu_run() Paolo Bonzini
  2026-05-13 17:49 ` [PATCH 2/3] KVM: SVM: Macrofy GPR swapping in __svm_vcpu_run() Paolo Bonzini
@ 2026-05-13 17:49 ` Paolo Bonzini
  2 siblings, 0 replies; 5+ messages in thread
From: Paolo Bonzini @ 2026-05-13 17:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: chang.seok.bae

From: "Chang S. Bae" <chang.seok.bae@intel.com>

Convert the SEV-ES entry code to use macros for saving guest GPRs,
following VMX/SVM paths. Drop now-unused register offsets and
__VCPU_REGS_* defines.

No functional change intended.

Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Message-ID: <20260512011502.53072-4-chang.seok.bae@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/kvm_host.h      | 16 ++++++++--------
 arch/x86/include/asm/kvm_vcpu_regs.h | 11 -----------
 arch/x86/kvm/svm/vmenter.S           | 21 ++-------------------
 3 files changed, 10 insertions(+), 38 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 8a53ca619570..53527b0550c7 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -182,14 +182,14 @@ enum kvm_reg {
 	VCPU_REGS_RSI = __VCPU_REGS_RSI,
 	VCPU_REGS_RDI = __VCPU_REGS_RDI,
 #ifdef CONFIG_X86_64
-	VCPU_REGS_R8  = __VCPU_REGS_R8,
-	VCPU_REGS_R9  = __VCPU_REGS_R9,
-	VCPU_REGS_R10 = __VCPU_REGS_R10,
-	VCPU_REGS_R11 = __VCPU_REGS_R11,
-	VCPU_REGS_R12 = __VCPU_REGS_R12,
-	VCPU_REGS_R13 = __VCPU_REGS_R13,
-	VCPU_REGS_R14 = __VCPU_REGS_R14,
-	VCPU_REGS_R15 = __VCPU_REGS_R15,
+	VCPU_REGS_R8  = 8,
+	VCPU_REGS_R9,
+	VCPU_REGS_R10,
+	VCPU_REGS_R11,
+	VCPU_REGS_R12,
+	VCPU_REGS_R13,
+	VCPU_REGS_R14,
+	VCPU_REGS_R15,
 #endif
 	NR_VCPU_GENERAL_PURPOSE_REGS,
 
diff --git a/arch/x86/include/asm/kvm_vcpu_regs.h b/arch/x86/include/asm/kvm_vcpu_regs.h
index 7c12a1fd1ffc..22efe651c9fc 100644
--- a/arch/x86/include/asm/kvm_vcpu_regs.h
+++ b/arch/x86/include/asm/kvm_vcpu_regs.h
@@ -11,17 +11,6 @@
 #define __VCPU_REGS_RSI  6
 #define __VCPU_REGS_RDI  7
 
-#ifdef CONFIG_X86_64
-#define __VCPU_REGS_R8   8
-#define __VCPU_REGS_R9   9
-#define __VCPU_REGS_R10 10
-#define __VCPU_REGS_R11 11
-#define __VCPU_REGS_R12 12
-#define __VCPU_REGS_R13 13
-#define __VCPU_REGS_R14 14
-#define __VCPU_REGS_R15 15
-#endif
-
 #ifdef __ASSEMBLER__
 
 #define REG_NUM_INVALID		100
diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S
index 06a8cb58f187..99701892f8ec 100644
--- a/arch/x86/kvm/svm/vmenter.S
+++ b/arch/x86/kvm/svm/vmenter.S
@@ -211,18 +211,7 @@ SYM_FUNC_END(__svm_vcpu_run)
 
 #ifdef CONFIG_KVM_AMD_SEV
 
-
-#ifdef CONFIG_X86_64
 #define SEV_ES_GPRS_BASE 0x300
-#define SEV_ES_RBX	(SEV_ES_GPRS_BASE + __VCPU_REGS_RBX * WORD_SIZE)
-#define SEV_ES_RBP	(SEV_ES_GPRS_BASE + __VCPU_REGS_RBP * WORD_SIZE)
-#define SEV_ES_RSI	(SEV_ES_GPRS_BASE + __VCPU_REGS_RSI * WORD_SIZE)
-#define SEV_ES_RDI	(SEV_ES_GPRS_BASE + __VCPU_REGS_RDI * WORD_SIZE)
-#define SEV_ES_R12	(SEV_ES_GPRS_BASE + __VCPU_REGS_R12 * WORD_SIZE)
-#define SEV_ES_R13	(SEV_ES_GPRS_BASE + __VCPU_REGS_R13 * WORD_SIZE)
-#define SEV_ES_R14	(SEV_ES_GPRS_BASE + __VCPU_REGS_R14 * WORD_SIZE)
-#define SEV_ES_R15	(SEV_ES_GPRS_BASE + __VCPU_REGS_R15 * WORD_SIZE)
-#endif
 
 /**
  * __svm_sev_es_vcpu_run - Run a SEV-ES vCPU via a transition to SVM guest mode
@@ -237,19 +226,13 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run)
 	 * Except for RAX and RSP, all GPRs are restored on #VMEXIT, but not
 	 * saved on VMRUN.
 	 */
-	mov %rbp, SEV_ES_RBP (%rdx)
-	mov %r15, SEV_ES_R15 (%rdx)
-	mov %r14, SEV_ES_R14 (%rdx)
-	mov %r13, SEV_ES_R13 (%rdx)
-	mov %r12, SEV_ES_R12 (%rdx)
-	mov %rbx, SEV_ES_RBX (%rdx)
+	STORE_REGS %rdx, SEV_ES_GPRS_BASE, %rbp, %r15, %r14, %r13, %r12, %rbx
 
 	/*
 	 * Save volatile registers that hold arguments that are needed after
 	 * #VMEXIT (RDI=@svm and RSI=@enter_flags).
 	 */
-	mov %rdi, SEV_ES_RDI (%rdx)
-	mov %rsi, SEV_ES_RSI (%rdx)
+	STORE_REGS %rdx, SEV_ES_GPRS_BASE, %rdi, %rsi
 
 	/* Clobbers RAX, RCX, and RDX (@hostsa), consumes RDI (@svm). */
 	RESTORE_GUEST_SPEC_CTRL
-- 
2.52.0


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH 1/3] KVM: VMX: Macrofy GPR swapping in __vmx_vcpu_run()
  2026-05-13 17:49 ` [PATCH 1/3] KVM: VMX: Macrofy GPR swapping in __vmx_vcpu_run() Paolo Bonzini
@ 2026-05-14 19:30   ` Sean Christopherson
  0 siblings, 0 replies; 5+ messages in thread
From: Sean Christopherson @ 2026-05-14 19:30 UTC (permalink / raw)
  To: Paolo Bonzini; +Cc: linux-kernel, kvm, chang.seok.bae, x86

On Wed, May 13, 2026, Paolo Bonzini wrote:
> From: "Chang S. Bae" <chang.seok.bae@intel.com>
> 
> Convert the repeated register save/restore sequences into macros to
> simplify the VM entry code. 

This is not simpler.  Maybe it ends up being less verbose, but I don't see how
anyone can claim this is simpler.  E.g. for people like me that aren't already
familiar with the .ifc directive, the R32_NUM macro is inscrutable.  I can at
least suss out what e.g. LOAD_REGS and friends are doing, but claiming the code
is "simpler" is rather ridiculous.

> This can also make it easier to extend for additional registers.

For me, this needs to be the focal point of the changelog, and it needs to be
written with --verbose, because the impact of APX on the VM-Entry/VM-Exit code
isn't so obvious that a one-line "this makes future life easier" sufficiently
justifies the macro magic.  And that's coming from someone that generally loves
macro magic :-)
 
> diff --git a/arch/x86/include/asm/kvm_vcpu_regs.h b/arch/x86/include/asm/kvm_vcpu_regs.h
> index 1af2cb59233b..7c12a1fd1ffc 100644
> --- a/arch/x86/include/asm/kvm_vcpu_regs.h
> +++ b/arch/x86/include/asm/kvm_vcpu_regs.h
> @@ -22,4 +22,126 @@
>  #define __VCPU_REGS_R15 15
>  #endif
>  
> +#ifdef __ASSEMBLER__
> +
> +#define REG_NUM_INVALID		100
> +
> +	.macro R32_NUM opd r32
> +	\opd = REG_NUM_INVALID
> +	.ifc \r32,%eax
> +	\opd = __VCPU_REGS_EAX
> +	.endif
> +	.ifc \r32,%ecx
> +	\opd = __VCPU_REGS_ECX
> +	.endif
> +	.ifc \r32,%edx
> +	\opd = __VCPU_REGS_EDX
> +	.endif
> +	.ifc \r32,%ebx
> +	\opd = __VCPU_REGS_EBX
> +	.endif
> +	.ifc \r32,%esp
> +	\opd = __VCPU_REGS_ESP
> +	.endif
> +	.ifc \r32,%ebp
> +	\opd = __VCPU_REGS_EBP
> +	.endif
> +	.ifc \r32,%esi
> +	\opd = __VCPU_REGS_ESI
> +	.endif
> +	.ifc \r32,%edi
> +	\opd = __VCPU_REGS_EDI
> +	.endif
> +#ifdef CONFIG_X86_64
> +	.ifc \r32,%r8d
> +	\opd = 8
> +	.endif
> +	.ifc \r32,%r9d
> +	\opd = 9
> +	.endif
> +	.ifc \r32,%r10d
> +	\opd = 10
> +	.endif
> +	.ifc \r32,%r11d
> +	\opd = 11
> +	.endif
> +	.ifc \r32,%r12d
> +	\opd = 12
> +	.endif
> +	.ifc \r32,%r13d
> +	\opd = 13
> +	.endif
> +	.ifc \r32,%r14d
> +	\opd = 14
> +	.endif
> +	.ifc \r32,%r15d
> +	\opd = 15
> +	.endif
> +#endif
> +	.endm
> +
> +	.macro R64_NUM opd r64
> +	\opd = REG_NUM_INVALID
> +#ifdef CONFIG_X86_64
> +	.ifc \r64,%rax
> +	\opd = __VCPU_REGS_RAX
> +	.endif
> +	.ifc \r64,%rcx
> +	\opd = __VCPU_REGS_RCX
> +	.endif
> +	.ifc \r64,%rdx
> +	\opd = __VCPU_REGS_RDX
> +	.endif
> +	.ifc \r64,%rbx
> +	\opd = __VCPU_REGS_RBX
> +	.endif
> +	.ifc \r64,%rsp
> +	\opd = __VCPU_REGS_RSP
> +	.endif
> +	.ifc \r64,%rbp
> +	\opd = __VCPU_REGS_RBP
> +	.endif
> +	.ifc \r64,%rsi
> +	\opd = __VCPU_REGS_RSI
> +	.endif
> +	.ifc \r64,%rdi
> +	\opd = __VCPU_REGS_RDI
> +	.endif
> +	.ifc \r64,%r8
> +	\opd = 8
> +	.endif
> +	.ifc \r64,%r9
> +	\opd = 9
> +	.endif
> +	.ifc \r64,%r10
> +	\opd = 10
> +	.endif
> +	.ifc \r64,%r11
> +	\opd = 11
> +	.endif
> +	.ifc \r64,%r12
> +	\opd = 12
> +	.endif
> +	.ifc \r64,%r13
> +	\opd = 13
> +	.endif
> +	.ifc \r64,%r14
> +	\opd = 14
> +	.endif
> +	.ifc \r64,%r15
> +	\opd = 15
> +	.endif
> +#endif
> +	.endm
> +
> +.macro REG_NUM reg_num reg
> +#ifdef CONFIG_X86_64
> +	R64_NUM \reg_num \reg
> +#else
> +	R32_NUM \reg_num \reg
> +#endif
> +.endm
> +
> +#endif
> +
>  #endif /* _ASM_X86_KVM_VCPU_REGS_H */
> diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S
> index f523d9e49839..6a91e1383e8f 100644
> --- a/arch/x86/kvm/svm/vmenter.S
> +++ b/arch/x86/kvm/svm/vmenter.S
> @@ -4,13 +4,10 @@
>  #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"
>  #include "vmenter.h"
>  
> -#define WORD_SIZE (BITS_PER_LONG / 8)
> -
>  /* Intentionally omit RAX as it's context switched by hardware */
>  #define VCPU_RCX	(SVM_vcpu_arch_regs + __VCPU_REGS_RCX * WORD_SIZE)
>  #define VCPU_RDX	(SVM_vcpu_arch_regs + __VCPU_REGS_RDX * WORD_SIZE)
> diff --git a/arch/x86/kvm/vmenter.h b/arch/x86/kvm/vmenter.h
> index ba3f71449c62..44574806cb02 100644
> --- a/arch/x86/kvm/vmenter.h
> +++ b/arch/x86/kvm/vmenter.h
> @@ -2,6 +2,8 @@
>  #ifndef __KVM_X86_VMENTER_H
>  #define __KVM_X86_VMENTER_H
>  
> +#include <asm/kvm_vcpu_regs.h>
> +
>  #define KVM_ENTER_VMRESUME			BIT(0)
>  #define KVM_ENTER_SAVE_SPEC_CTRL		BIT(1)
>  #define KVM_ENTER_CLEAR_CPU_BUFFERS_FOR_MMIO	BIT(2)
> @@ -76,5 +78,46 @@
>  	wrmsr
>  .endm
>  
> +#define WORD_SIZE (BITS_PER_LONG / 8)
> +
> +.macro LOAD_REGS src:req, regs_ofs:req, regs:vararg
> +.irp reg, \regs
> +	REG_NUM reg_num \reg
> +	.if reg_num <> REG_NUM_INVALID
> +	mov (\regs_ofs + reg_num * WORD_SIZE)(\src), \reg
> +	.else
> +	.err invalid register \reg
> +	.endif
> +.endr
> +.endm
> +
> +.macro STORE_REGS dst:req, regs_ofs:req, regs:vararg
> +.irp reg, \regs
> +	REG_NUM reg_num \reg
> +	.if reg_num <> REG_NUM_INVALID
> +	mov \reg, (\regs_ofs + reg_num * WORD_SIZE)(\dst)
> +	.else
> +	.err invalid register \reg
> +	.endif
> +.endr
> +.endm
> +
> +.macro POP_REGS dst:req, regs_ofs:req, regs:vararg
> +.irp reg, \regs
> +	REG_NUM reg_num \reg
> +	.if reg_num <> REG_NUM_INVALID
> +	pop (\regs_ofs + reg_num * WORD_SIZE)(\dst)
> +	.else
> +	.err invalid register \reg
> +	.endif
> +.endr
> +.endm
> +
> +.macro CLEAR_REGS regs:vararg
> +.irp reg, \regs
> +	xorl \reg, \reg
> +.endr
> +.endm
> +
>  #endif /* __ASSEMBLER__ */
>  #endif /* __KVM_X86_VMENTER_H */
> diff --git a/arch/x86/kvm/vmx/vmenter.S b/arch/x86/kvm/vmx/vmenter.S
> index 7e4dc17fc0b8..4b7aaa7430fb 100644
> --- a/arch/x86/kvm/vmx/vmenter.S
> +++ b/arch/x86/kvm/vmx/vmenter.S
> @@ -2,35 +2,12 @@
>  #include <linux/linkage.h>
>  #include <asm/asm.h>
>  #include <asm/bitsperlong.h>
> -#include <asm/kvm_vcpu_regs.h>
>  #include <asm/nospec-branch.h>
>  #include <asm/percpu.h>
>  #include <asm/segment.h>
>  #include "kvm-asm-offsets.h"
>  #include "vmenter.h"
>  
> -#define WORD_SIZE (BITS_PER_LONG / 8)
> -
> -#define VCPU_RAX	(VMX_vcpu_arch_regs + __VCPU_REGS_RAX * WORD_SIZE)
> -#define VCPU_RCX	(VMX_vcpu_arch_regs + __VCPU_REGS_RCX * WORD_SIZE)
> -#define VCPU_RDX	(VMX_vcpu_arch_regs + __VCPU_REGS_RDX * WORD_SIZE)
> -#define VCPU_RBX	(VMX_vcpu_arch_regs + __VCPU_REGS_RBX * WORD_SIZE)
> -/* Intentionally omit RSP as it's context switched by hardware */
> -#define VCPU_RBP	(VMX_vcpu_arch_regs + __VCPU_REGS_RBP * WORD_SIZE)
> -#define VCPU_RSI	(VMX_vcpu_arch_regs + __VCPU_REGS_RSI * WORD_SIZE)
> -#define VCPU_RDI	(VMX_vcpu_arch_regs + __VCPU_REGS_RDI * WORD_SIZE)
> -
> -#ifdef CONFIG_X86_64
> -#define VCPU_R8		(VMX_vcpu_arch_regs + __VCPU_REGS_R8  * WORD_SIZE)
> -#define VCPU_R9		(VMX_vcpu_arch_regs + __VCPU_REGS_R9  * WORD_SIZE)
> -#define VCPU_R10	(VMX_vcpu_arch_regs + __VCPU_REGS_R10 * WORD_SIZE)
> -#define VCPU_R11	(VMX_vcpu_arch_regs + __VCPU_REGS_R11 * WORD_SIZE)
> -#define VCPU_R12	(VMX_vcpu_arch_regs + __VCPU_REGS_R12 * WORD_SIZE)
> -#define VCPU_R13	(VMX_vcpu_arch_regs + __VCPU_REGS_R13 * WORD_SIZE)
> -#define VCPU_R14	(VMX_vcpu_arch_regs + __VCPU_REGS_R14 * WORD_SIZE)
> -#define VCPU_R15	(VMX_vcpu_arch_regs + __VCPU_REGS_R15 * WORD_SIZE)
> -#endif
> -
>  .macro VMX_DO_EVENT_IRQOFF call_insn call_target
>  	/*
>  	 * Unconditionally create a stack frame, getting the correct RSP on the
> @@ -114,25 +91,18 @@ SYM_FUNC_START(__vmx_vcpu_run)
>  	 * an LFENCE to stop speculation from skipping the wrmsr.
>  	 */
>  
> -	/* Load guest registers.  Don't clobber flags. */
> -	mov VCPU_RAX(%_ASM_DI), %_ASM_AX
> -	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
> +	/*
> +	 * Load guest registers.  Don't clobber flags. Intentionally omit
> +	 * %_ASM_SP as it's context switched by hardware
> +	 */
> +	LOAD_REGS %_ASM_DI, VMX_vcpu_arch_regs, \
> +		  %_ASM_AX, %_ASM_CX, %_ASM_DX, %_ASM_BX, %_ASM_BP, %_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
> +	LOAD_REGS %_ASM_DI, VMX_vcpu_arch_regs, \
> +		  %r8, %r9, %r10, %r11, %r12, %r13, %r14, %r15
>  #endif
>  	/* Load guest RDI.  This kills the @vmx pointer! */
> -	mov VCPU_RDI(%_ASM_DI), %_ASM_DI
> +	LOAD_REGS %_ASM_DI, VMX_vcpu_arch_regs, %_ASM_DI
>  
>  	/*
>  	 * Note, ALTERNATIVE_2 works in reverse order.  If CLEAR_CPU_BUF_VM is
> @@ -187,23 +157,16 @@ SYM_INNER_LABEL_ALIGN(vmx_vmexit, SYM_L_GLOBAL)
>  	/* Reload @vmx to RDI. */
>  	mov 2*WORD_SIZE(%_ASM_SP), %_ASM_DI
>  
> -	/* Save all guest registers, including RDI from the stack */
> -	mov %_ASM_AX, VCPU_RAX(%_ASM_DI)
> -	mov %_ASM_CX, VCPU_RCX(%_ASM_DI)
> -	mov %_ASM_DX, VCPU_RDX(%_ASM_DI)
> -	mov %_ASM_BX, VCPU_RBX(%_ASM_DI)
> -	mov %_ASM_BP, VCPU_RBP(%_ASM_DI)
> -	mov %_ASM_SI, VCPU_RSI(%_ASM_DI)
> -	pop           VCPU_RDI(%_ASM_DI)
> +	/*
> +	 * Save all guest registers, including RDI from the stack. Intentionally
> +	 * omit %_ASM_SP as it's context switched by hardware
> +	 */
> +	STORE_REGS %_ASM_DI, VMX_vcpu_arch_regs, \
> +		   %_ASM_AX, %_ASM_CX, %_ASM_DX, %_ASM_BX, %_ASM_BP, %_ASM_SI
> +	POP_REGS   %_ASM_DI, VMX_vcpu_arch_regs, %_ASM_DI
>  #ifdef CONFIG_X86_64
> -	mov %r8,  VCPU_R8 (%_ASM_DI)
> -	mov %r9,  VCPU_R9 (%_ASM_DI)
> -	mov %r10, VCPU_R10(%_ASM_DI)
> -	mov %r11, VCPU_R11(%_ASM_DI)
> -	mov %r12, VCPU_R12(%_ASM_DI)
> -	mov %r13, VCPU_R13(%_ASM_DI)
> -	mov %r14, VCPU_R14(%_ASM_DI)
> -	mov %r15, VCPU_R15(%_ASM_DI)
> +	STORE_REGS %_ASM_DI, VMX_vcpu_arch_regs, \
> +		   %r8, %r9, %r10, %r11, %r12, %r13, %r14, %r15
>  #endif
>  
>  	/* Clear return value to indicate VM-Exit (as opposed to VM-Fail). */
> @@ -220,21 +183,9 @@ SYM_INNER_LABEL_ALIGN(vmx_vmexit, SYM_L_GLOBAL)
>  	 * VM-Exit and RBX is explicitly loaded with 0 or 1 to hold the return
>  	 * value.
>  	 */
> -	xor %eax, %eax
> -	xor %ecx, %ecx
> -	xor %edx, %edx
> -	xor %ebp, %ebp
> -	xor %esi, %esi
> -	xor %edi, %edi
> +	CLEAR_REGS %eax, %ecx, %edx, %ebp, %esi, %edi
>  #ifdef CONFIG_X86_64
> -	xor %r8d,  %r8d
> -	xor %r9d,  %r9d
> -	xor %r10d, %r10d
> -	xor %r11d, %r11d
> -	xor %r12d, %r12d
> -	xor %r13d, %r13d
> -	xor %r14d, %r14d
> -	xor %r15d, %r15d
> +	CLEAR_REGS %r8d, %r9d, %r10d, %r11d, %r12d, %r13d, %r14d, %r15d
>  #endif
>  
>  	/*
> -- 
> 2.52.0
> 
> 

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2026-05-14 19:30 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
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2026-05-13 17:49 [PATCH 0/3] KVM: Macrofy GPR swapping in assembly code Paolo Bonzini
2026-05-13 17:49 ` [PATCH 1/3] KVM: VMX: Macrofy GPR swapping in __vmx_vcpu_run() Paolo Bonzini
2026-05-14 19:30   ` Sean Christopherson
2026-05-13 17:49 ` [PATCH 2/3] KVM: SVM: Macrofy GPR swapping in __svm_vcpu_run() Paolo Bonzini
2026-05-13 17:49 ` [PATCH 3/3] KVM: SEV: Macrofy GPR swapping in __svm_sev_es_vcpu_run() Paolo Bonzini

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