virtio_ccw_synchronize_cbs() assumes the device uses adapter interrupts
when vcdev->airq_info is not NULL. If registering adapter indicators
fails, virtio_ccw_find_vqs() falls back to classic interrupts but can
leave airq_info set.
With VIRTIO_HARDEN_NOTIFICATION enabled,
virtio_ccw_int_handler() invokes callbacks under vcdev->irq_lock.
synchronize_cbs() instead takes the indicator area lock, so it does
not synchronize with those callbacks.
Use vcdev->is_thinint, which the fallback clears, to select the lock.
Keep the airq_info check because is_thinint can be set before the
first find_vqs() call, when airq_info is still NULL.
Fixes: 3a232277c1ac ("virtio-ccw: implement synchronize_cbs()")
Assisted-by: LLM
Signed-off-by: Karl Mehltretter <[email protected]>
---
drivers/s390/virtio/virtio_ccw.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
index bab6cad3fd5c..b90299205698 100644
--- a/drivers/s390/virtio/virtio_ccw.c
+++ b/drivers/s390/virtio/virtio_ccw.c
@@ -1062,7 +1062,7 @@ static void virtio_ccw_synchronize_cbs(struct
virtio_device *vdev)
struct virtio_ccw_device *vcdev = to_vc_device(vdev);
struct airq_info *info = vcdev->airq_info;
- if (info) {
+ if (vcdev->is_thinint && info) {
/*
* This device uses adapter interrupts: synchronize with
* vring_interrupt() called by virtio_airq_handler()
--
2.39.5 (Apple Git-154)
