From: Xin Li <xin@zytor.com>

Rename the WRMSR fastpath API to drop "irqoff", as that information is
redundant (the fastpath always runs with IRQs disabled), and to prepare
for adding a fastpath for the immediate variant of WRMSRNS.

No functional change intended.

Signed-off-by: Xin Li (Intel) <xin@zytor.com>
[sean: split to separate patch, write changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/svm/svm.c | 2 +-
 arch/x86/kvm/vmx/vmx.c | 2 +-
 arch/x86/kvm/x86.c     | 4 ++--
 arch/x86/kvm/x86.h     | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index f7e1e665a826..ca550c4fa174 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4197,7 +4197,7 @@ static fastpath_t svm_exit_handlers_fastpath(struct kvm_vcpu *vcpu)
 	case SVM_EXIT_MSR:
 		if (!control->exit_info_1)
 			break;
-		return handle_fastpath_set_msr_irqoff(vcpu);
+		return handle_fastpath_wrmsr(vcpu);
 	case SVM_EXIT_HLT:
 		return handle_fastpath_hlt(vcpu);
 	case SVM_EXIT_INVD:
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 95765db52992..ae2c8c10e5d2 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7170,7 +7170,7 @@ static fastpath_t vmx_exit_handlers_fastpath(struct kvm_vcpu *vcpu,
 
 	switch (vmx_get_exit_reason(vcpu).basic) {
 	case EXIT_REASON_MSR_WRITE:
-		return handle_fastpath_set_msr_irqoff(vcpu);
+		return handle_fastpath_wrmsr(vcpu);
 	case EXIT_REASON_PREEMPTION_TIMER:
 		return handle_fastpath_preemption_timer(vcpu, force_immediate_exit);
 	case EXIT_REASON_HLT:
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d3afb875133e..6470f0ab2060 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2142,7 +2142,7 @@ static inline bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu)
 	       kvm_request_pending(vcpu) || xfer_to_guest_mode_work_pending();
 }
 
-fastpath_t handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu)
+fastpath_t handle_fastpath_wrmsr(struct kvm_vcpu *vcpu)
 {
 	u64 data = kvm_read_edx_eax(vcpu);
 	u32 msr = kvm_rcx_read(vcpu);
@@ -2167,7 +2167,7 @@ fastpath_t handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu)
 
 	return EXIT_FASTPATH_REENTER_GUEST;
 }
-EXPORT_SYMBOL_GPL(handle_fastpath_set_msr_irqoff);
+EXPORT_SYMBOL_GPL(handle_fastpath_wrmsr);
 
 /*
  * Adapt set_msr() to msr_io()'s calling convention
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 46220b04cdf2..2dab9c9d6199 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -437,7 +437,7 @@ int x86_decode_emulated_instruction(struct kvm_vcpu *vcpu, int emulation_type,
 				    void *insn, int insn_len);
 int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
 			    int emulation_type, void *insn, int insn_len);
-fastpath_t handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu);
+fastpath_t handle_fastpath_wrmsr(struct kvm_vcpu *vcpu);
 fastpath_t handle_fastpath_hlt(struct kvm_vcpu *vcpu);
 fastpath_t handle_fastpath_invd(struct kvm_vcpu *vcpu);
 
-- 
2.50.1.565.gc32cd1483b-goog

On 8/5/2025 1:22 PM, Sean Christopherson wrote:
> From: Xin Li <xin@zytor.com>
> 
> Rename the WRMSR fastpath API to drop "irqoff", as that information is
> redundant (the fastpath always runs with IRQs disabled), and to prepare
> for adding a fastpath for the immediate variant of WRMSRNS.
> 
> No functional change intended.
> 

I think it makes sense to add:

Suggested-by: Sean Christopherson <seanjc@google.com>

I didn't add it in v2 because the changes are part of a patch that
handles the immediate form MSR instructions.

> Signed-off-by: Xin Li (Intel) <xin@zytor.com>
> [sean: split to separate patch, write changelog]
> Signed-off-by: Sean Christopherson <seanjc@google.com>