From: Sean Christopherson <seanjc@google.com>
Date: Wed, 18 Feb 2026 23:09:57 +0000 (-0800)
Subject: KVM: nSVM: Move vmcb_ctrl_area_cached.bus_lock_rip to svm_nested_state
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=af75470944f4c978956001cd6034f67469957c1b;p=thirdparty%2Fkernel%2Flinux.git

KVM: nSVM: Move vmcb_ctrl_area_cached.bus_lock_rip to svm_nested_state

Move "bus_lock_rip" from "vmcb_ctrl_area_cached" to "svm_nested_state" as
"last_bus_lock_rip" to more accurately reflect what it tracks, and because
it is NOT a cached vmcb12 control field.  The misplaced field isn't all
that apparent in the current code base, as KVM uses "svm->nested.ctl"
broadly, but the bad placement becomes glaringly obvious if
"svm->nested.ctl" is captured as a local "vmcb12_ctrl" variable.

No functional change intended.

Reviewed-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Link: https://patch.msgid.link/20260218230958.2877682-8-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
---

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index c965d10f31875..dc4cca7df47ec 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -850,7 +850,7 @@ static void nested_vmcb02_prepare_control(struct vcpu_svm *svm)
 	 * L1 re-enters L2, the same instruction will trigger a VM-Exit and the
 	 * entire cycle start over.
 	 */
-	if (vmcb02->save.rip && (svm->nested.ctl.bus_lock_rip == vmcb02->save.rip))
+	if (vmcb02->save.rip && (svm->nested.last_bus_lock_rip == vmcb02->save.rip))
 		vmcb02->control.bus_lock_counter = 1;
 	else
 		vmcb02->control.bus_lock_counter = 0;
@@ -1255,11 +1255,11 @@ void nested_svm_vmexit(struct vcpu_svm *svm)
 	}
 
 	/*
-	 * Invalidate bus_lock_rip unless KVM is still waiting for the guest
-	 * to make forward progress before re-enabling bus lock detection.
+	 * Invalidate last_bus_lock_rip unless KVM is still waiting for the
+	 * guest to make forward progress before re-enabling bus lock detection.
 	 */
 	if (!vmcb02->control.bus_lock_counter)
-		svm->nested.ctl.bus_lock_rip = INVALID_GPA;
+		svm->nested.last_bus_lock_rip = INVALID_GPA;
 
 	nested_svm_copy_common_state(svm->nested.vmcb02.ptr, svm->vmcb01.ptr);
 
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 1901e9feff51a..62501c1201124 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3271,7 +3271,7 @@ static int bus_lock_exit(struct kvm_vcpu *vcpu)
 	vcpu->arch.complete_userspace_io = complete_userspace_buslock;
 
 	if (is_guest_mode(vcpu))
-		svm->nested.ctl.bus_lock_rip = vcpu->arch.cui_linear_rip;
+		svm->nested.last_bus_lock_rip = vcpu->arch.cui_linear_rip;
 
 	return 0;
 }
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 267ef8a3359b4..6c3b3fae91ec1 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -174,7 +174,6 @@ struct vmcb_ctrl_area_cached {
 	u64 nested_cr3;
 	u64 virt_ext;
 	u32 clean;
-	u64 bus_lock_rip;
 	union {
 #if IS_ENABLED(CONFIG_HYPERV) || IS_ENABLED(CONFIG_KVM_HYPERV)
 		struct hv_vmcb_enlightenments hv_enlightenments;
@@ -189,6 +188,7 @@ struct svm_nested_state {
 	u64 vm_cr_msr;
 	u64 vmcb12_gpa;
 	u64 last_vmcb12_gpa;
+	u64 last_bus_lock_rip;
 
 	/*
 	 * The MSR permissions map used for vmcb02, which is the merge result