FAILED: patch "[PATCH] KVM: arm64: vgic-its: Fix MOVALL handling of source" failed to apply to 6.12-stable tree

PATCH New [email protected] 2 participants 2 messages Oct 5 – Oct 6

Subsystems (3)

Stable branch arm64 KVM arm64

lore

Share & tools

lore

[email protected]

author maintainer

2026-10-05 14:36 UTC #0 lore raw

The patch below does not apply to the 6.12-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 <[email protected]>.

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-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 751f4641560be8568dcc5af400c0e55a283abf51
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026100519-line-generous-1624@gregkh' --subject-prefix 'PATCH 6.12.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

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

From 751f4641560be8568dcc5af400c0e55a283abf51 Mon Sep 17 00:00:00 2001
From: Marc Zyngier <[email protected]>
Date: Tue, 29 Sep 2026 10:35:47 +0100
Subject: [PATCH] KVM: arm64: vgic-its: Fix MOVALL handling of source
redistributor

The MOVALL command moves the pending state of all LPIs targeting a given redistributor to another one. However, we seem to have lost the filtering on the source RD, which means we move all LPIs to the target.

Not quite what the spec mandates.

Hack update_affinity() to take an optional source vcpu that is used as a filter when non-NULL, restoring the filtering that was performed by vgic_copy_lpi_list() back in the days.

Fixes 11f4f8f3e6e06 ("KVM: arm64: vgic-its: Walk LPI xarray in vgic_its_cmd_handle_movall()")

Signed-off-by Marc Zyngier <[email protected]>

Cc [email protected]

Link https://patch.msgid.link/[email protected] open here

Signed-off-by Oliver Upton <[email protected]>

arch/arm64/kvm/vgic/vgic-its.c +8 -4

index 0904ae850c35..c10a11373e10 100644
@@ -319,12 +319,16 @@ static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
 	return ret;
 }
 
-static int update_affinity(struct vgic_irq *irq, struct kvm_vcpu *vcpu)
+static int update_affinity(struct vgic_irq *irq,
+			   struct kvm_vcpu *from_vcpu, struct kvm_vcpu *vcpu)
 {
 	struct its_vlpi_map map;
 	int ret;
 
 	guard(raw_spinlock_irqsave)(&irq->irq_lock);
+	if (from_vcpu && irq->target_vcpu != from_vcpu)
+		return 0;
+
 	irq->target_vcpu = vcpu;
 
 	if (!irq->hw)

@@ -362,7 +366,7 @@ static void update_affinity_ite(struct kvm *kvm, struct its_ite *ite)
 		return;
 
 	vcpu = collection_to_vcpu(kvm, ite->collection);
-	update_affinity(ite->irq, vcpu);
+	update_affinity(ite->irq, NULL, vcpu);
 }
 
 /*

@@ -856,7 +860,7 @@ static int vgic_its_cmd_handle_movi(struct kvm *kvm, struct vgic_its *its,
 
 	vgic_its_invalidate_cache(its);
 
-	return update_affinity(ite->irq, vcpu);
+	return update_affinity(ite->irq, NULL, vcpu);
 }
 
 static bool __is_visible_gfn_locked(struct vgic_its *its, gpa_t gpa)

@@ -1383,7 +1387,7 @@ static int vgic_its_cmd_handle_movall(struct kvm *kvm, struct vgic_its *its,
 		if (!irq)
 			continue;
 
-		update_affinity(irq, vcpu2);
+		update_affinity(irq, vcpu1, vcpu2);
 
 		vgic_put_irq(kvm, irq);
 	}

Marc Zyngier

maintainer

2026-10-06 10:45 UTC #1 lore raw

PATCH 1/1 KVM: arm64: vgic-its: Fix MOVALL handling of source redistributor

Not quite what the spec mandates.

Hack update_affinity() to take an optional source vcpu that is used as a filter when non-NULL, restoring the filtering that was performed by vgic_copy_lpi_list() back in the days.

Fixes 11f4f8f3e6e06 ("KVM: arm64: vgic-its: Walk LPI xarray in vgic_its_cmd_handle_movall()")

Signed-off-by Marc Zyngier <[email protected]>

Cc [email protected]

Link https://patch.msgid.link/[email protected] open here

Signed-off-by Oliver Upton <[email protected]>

(cherry picked from commit 751f4641560be8568dcc5af400c0e55a283abf51)

Signed-off-by Marc Zyngier <[email protected]>

---
 arch/arm64/kvm/vgic/vgic-its.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

arch/arm64/kvm/vgic/vgic-its.c +10 -4

index 4b56de3352053..5ba833a288813 100644
@@ -344,12 +344,18 @@ static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
 	return 0;
 }
 
-static int update_affinity(struct vgic_irq *irq, struct kvm_vcpu *vcpu)
+static int update_affinity(struct vgic_irq *irq,
+			   struct kvm_vcpu *from_vcpu, struct kvm_vcpu *vcpu)
 {
 	int ret = 0;
 	unsigned long flags;
 
 	raw_spin_lock_irqsave(&irq->irq_lock, flags);
+	if (from_vcpu && irq->target_vcpu != from_vcpu) {
+		raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
+		return 0;
+	}
+
 	irq->target_vcpu = vcpu;
 	raw_spin_unlock_irqrestore(&irq->irq_lock, flags);

@@ -391,7 +397,7 @@ static void update_affinity_ite(struct kvm *kvm, struct its_ite *ite)
 		return;
 
 	vcpu = collection_to_vcpu(kvm, ite->collection);
-	update_affinity(ite->irq, vcpu);
+	update_affinity(ite->irq, NULL, vcpu);
 }
 
 /*

@@ -869,7 +875,7 @@ static int vgic_its_cmd_handle_movi(struct kvm *kvm, struct vgic_its *its,
 
 	vgic_its_invalidate_cache(its);
 
-	return update_affinity(ite->irq, vcpu);
+	return update_affinity(ite->irq, NULL, vcpu);
 }
 
 static bool __is_visible_gfn_locked(struct vgic_its *its, gpa_t gpa)

@@ -1396,7 +1402,7 @@ static int vgic_its_cmd_handle_movall(struct kvm *kvm, struct vgic_its *its,
 		if (!irq)
 			continue;
 
-		update_affinity(irq, vcpu2);
+		update_affinity(irq, vcpu1, vcpu2);
 
 		vgic_put_irq(kvm, irq);
 	}

Signature · 1 line

2.47.3