FAILED: patch "[PATCH] KVM: VMX: Make handle_bus_lock_vmexit() a shared helper" failed to apply to 6.6-stable tree

[Sasha Levin <sashal@kernel.org>]

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 326fa2c9b4d3e6cab58c139eb55aaabd7179192e
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '20261107052950-failed-6.6-326fa2c9b4d3@kernel.org' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From 326fa2c9b4d3e6cab58c139eb55aaabd7179192e Mon Sep 17 00:00:00 2001
From: Xiaoyao Li <xiaoyao.li@intel.com>
Date: Wed, 19 Aug 2026 17:49:01 +0800
Subject: [PATCH] KVM: VMX: Make handle_bus_lock_vmexit() a shared helper

Move handle_bus_lock_vmexit() from vmx.c to main.c to make it a shared
helper so that TDX can use it for Bus Lock VM exit handling as well.
Rename it to add vt_ prefix to reflect that it is a helper for both VMX
and TDX.

Cc: stable@vger.kernel.org
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
Link: https://patch.msgid.link/20260819094903.3060020-8-xiaoyao.li@intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/vmx/common.h |  1 +
 arch/x86/kvm/vmx/main.c   | 11 +++++++++++
 arch/x86/kvm/vmx/vmx.c    | 13 +------------
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kvm/vmx/common.h b/arch/x86/kvm/vmx/common.h
index 7fce1bbabc78c..bbeec197a507a 100644
--- a/arch/x86/kvm/vmx/common.h
+++ b/arch/x86/kvm/vmx/common.h
@@ -203,5 +203,6 @@ static inline int __vt_handle_notify(struct kvm_vcpu *vcpu,
 }
 
 noinstr void vmx_handle_nmi(struct kvm_vcpu *vcpu);
+int vt_handle_bus_lock_vmexit(struct kvm_vcpu *vcpu);
 
 #endif /* __KVM_X86_VMX_COMMON_H */
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index ea0d825e556d2..835de375e8c8c 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -878,6 +878,17 @@ static int vt_gmem_max_mapping_level(struct kvm *kvm, kvm_pfn_t pfn,
 #define vt_op_tdx_only(name) NULL
 #endif /* CONFIG_KVM_INTEL_TDX */
 
+int vt_handle_bus_lock_vmexit(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * Hardware may or may not set the BUS_LOCK_DETECTED flag on BUS_LOCK
+	 * VM-Exits. Unconditionally set the flag here and leave the handling
+	 * to .handle_exit() callback.
+	 */
+	to_vt(vcpu)->exit_reason.bus_lock_detected = true;
+	return 1;
+}
+
 #define VMX_REQUIRED_APICV_INHIBITS				\
 	(BIT(APICV_INHIBIT_REASON_DISABLED) |			\
 	 BIT(APICV_INHIBIT_REASON_ABSENT) |			\
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 6df390ae8708f..3ba1e762e7e75 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6267,17 +6267,6 @@ static int handle_encls(struct kvm_vcpu *vcpu)
 }
 #endif /* CONFIG_X86_SGX_KVM */
 
-static int handle_bus_lock_vmexit(struct kvm_vcpu *vcpu)
-{
-	/*
-	 * Hardware may or may not set the BUS_LOCK_DETECTED flag on BUS_LOCK
-	 * VM-Exits. Unconditionally set the flag here and leave the handling to
-	 * vmx_handle_exit().
-	 */
-	to_vt(vcpu)->exit_reason.bus_lock_detected = true;
-	return 1;
-}
-
 static int handle_notify(struct kvm_vcpu *vcpu)
 {
 	unsigned long exit_qual = vmx_get_exit_qual(vcpu);
@@ -6366,7 +6355,7 @@ static int (*kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = {
 	[EXIT_REASON_VMFUNC]		      = handle_vmx_instruction,
 	[EXIT_REASON_PREEMPTION_TIMER]	      = handle_preemption_timer,
 	[EXIT_REASON_ENCLS]		      = handle_encls,
-	[EXIT_REASON_BUS_LOCK]                = handle_bus_lock_vmexit,
+	[EXIT_REASON_BUS_LOCK]                = vt_handle_bus_lock_vmexit,
 	[EXIT_REASON_NOTIFY]		      = handle_notify,
 	[EXIT_REASON_SEAMCALL]		      = handle_tdx_instruction,
 	[EXIT_REASON_TDCALL]		      = handle_tdx_instruction,
-- 
2.53.0