linux-kernel - [PATCH] KVM: SVM: Don't set GIF when clearing EFER.SVME

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Message-ID: <20251007224405.1914008-1-jmattson@google.com>
Date: Tue,  7 Oct 2025 15:44:00 -0700
From: Jim Mattson <jmattson@...gle.com>
To: Yosry Ahmed <yosry.ahmed@...ux.dev>, Sean Christopherson <seanjc@...gle.com>, 
	Paolo Bonzini <pbonzini@...hat.com>, Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>, 
	Borislav Petkov <bp@...en8.de>, Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org, 
	"H. Peter Anvin" <hpa@...or.com>, kvm@...r.kernel.org, linux-kernel@...r.kernel.org
Cc: Jim Mattson <jmattson@...gle.com>
Subject: [PATCH] KVM: SVM: Don't set GIF when clearing EFER.SVME

Clearing EFER.SVME is not architected to set GIF. Don't set GIF when
emulating a change to EFER that clears EFER.SVME.

This is covered in the discussion at
https://lore.kernel.org/all/5b8787b8-16e9-13dc-7fca-0dc441d673f9@citrix.com/.

Fixes: c513f484c558 ("KVM: nSVM: leave guest mode when clearing EFER.SVME")
Signed-off-by: Jim Mattson <jmattson@...gle.com>
---
 arch/x86/kvm/svm/svm.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 3a9fe0a8b78c..5387851a96da 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -223,7 +223,6 @@ int svm_set_efer(struct kvm_vcpu *vcpu, u64 efer)
 	if ((old_efer & EFER_SVME) != (efer & EFER_SVME)) {
 		if (!(efer & EFER_SVME)) {
 			svm_leave_nested(vcpu);
-			svm_set_gif(svm, true);
 			/* #GP intercept is still needed for vmware backdoor */
 			if (!enable_vmware_backdoor)
 				clr_exception_intercept(svm, GP_VECTOR);
-- 
2.51.0.710.ga91ca5db03-goog