FAILED: patch "[PATCH] virtio_mmio: disable IRQ wake before free_irq" failed to apply to 6.6-stable tree

PATCH New [email protected] 2 participants 3 messages Sep 16

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Stable branch virtio core

lore

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lore

[email protected]

author maintainer

2026-09-16 14:16 UTC #0 lore raw

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 <[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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x d14d693adb055e98ca705822ba6daebc18602d9a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026091637-greeting-apple-1005@gregkh' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

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

From d14d693adb055e98ca705822ba6daebc18602d9a Mon Sep 17 00:00:00 2001
From: Xiong Weimin <[email protected]>
Date: Wed, 5 Aug 2026 11:29:37 +0800
Subject: [PATCH] virtio_mmio: disable IRQ wake before free_irq

When the DT node has "wakeup-source", vm_find_vqs() calls enable_irq_wake() on the shared IRQ, but vm_del_vqs() freed that IRQ without a matching disable_irq_wake(). That leaves a wake reference behind and can warn on later free_irq()/request_irq() cycles.

Record whether enable_irq_wake() succeeded, and disable it in vm_del_vqs() before free_irq().

Fixes 02213273f72a ("virtio_mmio: add support to set IRQ of a virtio device as wakeup source")

Cc [email protected]

Signed-off-by Xiong Weimin <[email protected]>

Signed-off-by Michael S. Tsirkin <[email protected]>

Message-ID: <[email protected]>

drivers/virtio/virtio_mmio.c +13 -3

index 316f03b97356..faae58e3401a 100644
@@ -88,6 +88,9 @@ struct virtio_mmio_device {
 
 	void __iomem *base;
 	unsigned long version;
+
+	/* True if enable_irq_wake() succeeded for the shared IRQ. */
+	bool wake_irq_enabled;
 };
 
 /* Configuration interface */

@@ -336,11 +339,17 @@ static void vm_del_vqs(struct virtio_device *vdev)
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
 	struct virtqueue *vq, *n;
+	int irq = platform_get_irq(vm_dev->pdev, 0);
 
 	list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 		vm_del_vq(vq);
 
-	free_irq(platform_get_irq(vm_dev->pdev, 0), vm_dev);
+	if (vm_dev->wake_irq_enabled) {
+		disable_irq_wake(irq);
+		vm_dev->wake_irq_enabled = false;
+	}
+
+	free_irq(irq, vm_dev);
 }
 
 static void vm_synchronize_cbs(struct virtio_device *vdev)

@@ -467,8 +476,9 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 	if (err)
 		return err;
 
-	if (of_property_read_bool(vm_dev->pdev->dev.of_node, "wakeup-source"))
-		enable_irq_wake(irq);
+	if (of_property_read_bool(vm_dev->pdev->dev.of_node, "wakeup-source") &&
+	    !enable_irq_wake(irq))
+		vm_dev->wake_irq_enabled = true;
 
 	for (i = 0; i < nvqs; ++i) {
 		struct virtqueue_info *vqi = &vqs_info[i];

Sasha Levin

maintainer

2026-09-16 16:48 UTC #1 lore raw

PATCH 1/2 virtio-mmio: Remove virtqueue list from mmio device

From: Viresh Kumar <[email protected]>

[ Upstream commit 564a69ad90d15c782176e1a8c9e1c95661e1aed0 ]

The MMIO transport implementation creates a list of virtqueues for a virtio device, while the same is already available in the struct virtio_device.

Don't create a duplicate list, and use the other one instead.

While at it, fix the virtio_device_for_each_vq() macro to accept an argument like "&vm_dev->vdev" (which currently fails to build).

Signed-off-by Viresh Kumar <[email protected]>

Message-Id: <3e56c6f74002987e22f364d883cbad177cd9ad9c.1747827066.git.viresh.kumar@linaro.org>

Signed-off-by Michael S. Tsirkin <[email protected]>

Acked-by Jason Wang <[email protected]>

Stable-dep-of: d14d693adb05 ("virtio_mmio: disable IRQ wake before free_irq")

Signed-off-by Sasha Levin <[email protected]>

---
 drivers/virtio/virtio_mmio.c | 52 +++---------------------------------
 include/linux/virtio.h       |  2 +-
 2 files changed, 4 insertions(+), 50 deletions(-)

drivers/virtio/virtio_mmio.c +3 ~~-49~~

index 049c4f4ee56fa..33da642ea962a 100644
@@ -65,7 +65,6 @@
 #include <linux/platform_device.h>
 #include <linux/pm.h>
 #include <linux/slab.h>
-#include <linux/spinlock.h>
 #include <linux/virtio.h>
 #include <linux/virtio_config.h>
 #include <uapi/linux/virtio_mmio.h>

@@ -88,22 +87,8 @@ struct virtio_mmio_device {
 
 	void __iomem *base;
 	unsigned long version;
-
-	/* a list of queues so we can dispatch IRQs */
-	spinlock_t lock;
-	struct list_head virtqueues;
-};
-
-struct virtio_mmio_vq_info {
-	/* the actual virtqueue */
-	struct virtqueue *vq;
-
-	/* the list node for the virtqueues list */
-	struct list_head node;
 };
 
-
-
 /* Configuration interface */
 
 static u64 vm_get_features(struct virtio_device *vdev)

@@ -300,9 +285,8 @@ static bool vm_notify_with_data(struct virtqueue *vq)
 static irqreturn_t vm_interrupt(int irq, void *opaque)
 {
 	struct virtio_mmio_device *vm_dev = opaque;
-	struct virtio_mmio_vq_info *info;
+	struct virtqueue *vq;
 	unsigned long status;
-	unsigned long flags;
 	irqreturn_t ret = IRQ_NONE;
 
 	/* Read and acknowledge interrupts */

@@ -315,10 +299,8 @@ static irqreturn_t vm_interrupt(int irq, void *opaque)
 	}
 
 	if (likely(status & VIRTIO_MMIO_INT_VRING)) {
-		spin_lock_irqsave(&vm_dev->lock, flags);
-		list_for_each_entry(info, &vm_dev->virtqueues, node)
-			ret |= vring_interrupt(irq, info->vq);
-		spin_unlock_irqrestore(&vm_dev->lock, flags);
+		virtio_device_for_each_vq(&vm_dev->vdev, vq)
+			ret |= vring_interrupt(irq, vq);
 	}
 
 	return ret;

@@ -329,14 +311,8 @@ static irqreturn_t vm_interrupt(int irq, void *opaque)
 static void vm_del_vq(struct virtqueue *vq)
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
-	struct virtio_mmio_vq_info *info = vq->priv;
-	unsigned long flags;
 	unsigned int index = vq->index;
 
-	spin_lock_irqsave(&vm_dev->lock, flags);
-	list_del(&info->node);
-	spin_unlock_irqrestore(&vm_dev->lock, flags);
-
 	/* Select and deactivate the queue */
 	writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL);
 	if (vm_dev->version == 1) {

@@ -347,8 +323,6 @@ static void vm_del_vq(struct virtqueue *vq)
 	}
 
 	vring_del_virtqueue(vq);
-
-	kfree(info);
 }
 
 static void vm_del_vqs(struct virtio_device *vdev)

@@ -375,9 +349,7 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int in
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
 	bool (*notify)(struct virtqueue *vq);
-	struct virtio_mmio_vq_info *info;
 	struct virtqueue *vq;
-	unsigned long flags;
 	unsigned int num;
 	int err;

@@ -399,13 +371,6 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int in
 		goto error_available;
 	}
 
-	/* Allocate and fill out our active queue description */
-	info = kmalloc(sizeof(*info), GFP_KERNEL);
-	if (!info) {
-		err = -ENOMEM;
-		goto error_kmalloc;
-	}
-
 	num = readl(vm_dev->base + VIRTIO_MMIO_QUEUE_NUM_MAX);
 	if (num == 0) {
 		err = -ENOENT;

@@ -463,13 +428,6 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int in
 		writel(1, vm_dev->base + VIRTIO_MMIO_QUEUE_READY);
 	}
 
-	vq->priv = info;
-	info->vq = vq;
-
-	spin_lock_irqsave(&vm_dev->lock, flags);
-	list_add(&info->node, &vm_dev->virtqueues);
-	spin_unlock_irqrestore(&vm_dev->lock, flags);
-
 	return vq;
 
 error_bad_pfn:

@@ -481,8 +439,6 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int in
 		writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_READY);
 		WARN_ON(readl(vm_dev->base + VIRTIO_MMIO_QUEUE_READY));
 	}
-	kfree(info);
-error_kmalloc:
 error_available:
 	return ERR_PTR(err);
 }

@@ -627,8 +583,6 @@ static int virtio_mmio_probe(struct platform_device *pdev)
 	vm_dev->vdev.dev.release = virtio_mmio_release_dev;
 	vm_dev->vdev.config = &virtio_mmio_config_ops;
 	vm_dev->pdev = pdev;
-	INIT_LIST_HEAD(&vm_dev->virtqueues);
-	spin_lock_init(&vm_dev->lock);
 
 	vm_dev->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(vm_dev->base)) {

include/linux/virtio.h +1 -1

index 4cc614a383765..73b95651fe57f 100644
@@ -158,7 +158,7 @@ void virtio_reset_device(struct virtio_device *dev);
 size_t virtio_max_dma_size(const struct virtio_device *vdev);
 
 #define virtio_device_for_each_vq(vdev, vq) \
-	list_for_each_entry(vq, &vdev->vqs, list)
+	list_for_each_entry(vq, &(vdev)->vqs, list)
 
 /**
  * struct virtio_driver - operations for a virtio I/O driver

Signature · 1 line

2.53.0

Sasha Levin

maintainer

2026-09-16 16:48 UTC #2 lore raw

PATCH 2/2 virtio_mmio: disable IRQ wake before free_irq

From: Xiong Weimin <[email protected]>

[ Upstream commit d14d693adb055e98ca705822ba6daebc18602d9a ]

Record whether enable_irq_wake() succeeded, and disable it in vm_del_vqs() before free_irq().

Fixes 02213273f72a ("virtio_mmio: add support to set IRQ of a virtio device as wakeup source")

Cc [email protected]

Signed-off-by Xiong Weimin <[email protected]>

Signed-off-by Michael S. Tsirkin <[email protected]>

Message-ID: <[email protected]>

Signed-off-by Sasha Levin <[email protected]>

---
 drivers/virtio/virtio_mmio.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

drivers/virtio/virtio_mmio.c +13 -3

index 33da642ea962a..649e9d5aa1329 100644
@@ -87,6 +87,9 @@ struct virtio_mmio_device {
 
 	void __iomem *base;
 	unsigned long version;
+
+	/* True if enable_irq_wake() succeeded for the shared IRQ. */
+	bool wake_irq_enabled;
 };
 
 /* Configuration interface */

@@ -329,11 +332,17 @@ static void vm_del_vqs(struct virtio_device *vdev)
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
 	struct virtqueue *vq, *n;
+	int irq = platform_get_irq(vm_dev->pdev, 0);
 
 	list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 		vm_del_vq(vq);
 
-	free_irq(platform_get_irq(vm_dev->pdev, 0), vm_dev);
+	if (vm_dev->wake_irq_enabled) {
+		disable_irq_wake(irq);
+		vm_dev->wake_irq_enabled = false;
+	}
+
+	free_irq(irq, vm_dev);
 }
 
 static void vm_synchronize_cbs(struct virtio_device *vdev)

@@ -462,8 +471,9 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 	if (err)
 		return err;
 
-	if (of_property_read_bool(vm_dev->pdev->dev.of_node, "wakeup-source"))
-		enable_irq_wake(irq);
+	if (of_property_read_bool(vm_dev->pdev->dev.of_node, "wakeup-source") &&
+	    !enable_irq_wake(irq))
+		vm_dev->wake_irq_enabled = true;
 
 	for (i = 0; i < nvqs; ++i) {
 		if (!names[i]) {

Signature · 1 line

2.53.0