[PATCH 6.1.y 2/2] virtio_mmio: disable IRQ wake before free_irq

[Sasha Levin <sashal@kernel.org>]

From: Xiong Weimin <xiongweimin@kylinos.cn>

[ Upstream commit d14d693adb055e98ca705822ba6daebc18602d9a ]

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: stable@vger.kernel.org
Signed-off-by: Xiong Weimin <xiongweimin@kylinos.cn>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-ID: <20260805032937.1606737-1-xiongweimin@kylinos.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/virtio/virtio_mmio.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index 7909d4aec8a6e..6395b8fba0050 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -86,6 +86,9 @@ 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 */
@@ -318,11 +321,17 @@ 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)
@@ -445,8 +454,9 @@ 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]) {
-- 
2.53.0