linux-kernel - [PATCH v2 11/13] KVM: nSVM: Simplify nested_svm

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251110222922.613224-12-yosry.ahmed@linux.dev>
Date: Mon, 10 Nov 2025 22:29:20 +0000
From: Yosry Ahmed <yosry.ahmed@...ux.dev>
To: Sean Christopherson <seanjc@...gle.com>
Cc: Paolo Bonzini <pbonzini@...hat.com>,
	Jim Mattson <jmattson@...gle.com>,
	kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Yosry Ahmed <yosry.ahmed@...ux.dev>
Subject: [PATCH v2 11/13] KVM: nSVM: Simplify nested_svm_vmrun()

Call nested_svm_merge_msrpm() from enter_svm_guest_mode() if called from
the VMRUN path, instead of making the call in nested_svm_vmrun(). This
simplifies the flow of nested_svm_vmrun() and removes all jumps to
cleanup labels.

Signed-off-by: Yosry Ahmed <yosry.ahmed@...ux.dev>
---
 arch/x86/kvm/svm/nested.c | 28 +++++++++++++---------------
 1 file changed, 13 insertions(+), 15 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index a48668c36a191..89830380cebc5 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1020,6 +1020,9 @@ int enter_svm_guest_mode(struct kvm_vcpu *vcpu, u64 vmcb12_gpa, bool from_vmrun)
 
 	nested_svm_hv_update_vm_vp_ids(vcpu);
 
+	if (from_vmrun && !nested_svm_merge_msrpm(vcpu))
+		return -1;
+
 	return 0;
 }
 
@@ -1105,23 +1108,18 @@ int nested_svm_vmrun(struct kvm_vcpu *vcpu)
 
 	svm->nested.nested_run_pending = 1;
 
-	if (enter_svm_guest_mode(vcpu, vmcb12_gpa, true))
-		goto out_exit_err;
-
-	if (nested_svm_merge_msrpm(vcpu))
-		return ret;
-
-out_exit_err:
-	svm->nested.nested_run_pending = 0;
-	svm->nmi_l1_to_l2 = false;
-	svm->soft_int_injected = false;
+	if (enter_svm_guest_mode(vcpu, vmcb12_gpa, true)) {
+		svm->nested.nested_run_pending = 0;
+		svm->nmi_l1_to_l2 = false;
+		svm->soft_int_injected = false;
 
-	svm->vmcb->control.exit_code    = SVM_EXIT_ERR;
-	svm->vmcb->control.exit_code_hi = 0;
-	svm->vmcb->control.exit_info_1  = 0;
-	svm->vmcb->control.exit_info_2  = 0;
+		svm->vmcb->control.exit_code    = SVM_EXIT_ERR;
+		svm->vmcb->control.exit_code_hi = 0;
+		svm->vmcb->control.exit_info_1  = 0;
+		svm->vmcb->control.exit_info_2  = 0;
 
-	nested_svm_vmexit(svm);
+		nested_svm_vmexit(svm);
+	}
 	return ret;
 }
 
-- 
2.51.2.1041.gc1ab5b90ca-goog