Re: [PATCH] virtio-pmem: ignore empty queue notifications

[Michael Tokarev]

On 1/6/26 11:38, Li Chen wrote:

From: Li Chen <chenl...@chinatelecom.cn>

virtio_pmem_flush() treats a NULL return from virtqueue_pop() as a fatal
error and calls virtio_error(), which puts the device into NEEDS_RESET.

However, virtqueue handlers can be invoked when no element is available,
so an empty queue should be handled as a benign no-op.

With a Linux guest this avoids spurious NEEDS_RESET and the resulting
-EIO propagation (e.g. EXT4 journal abort and remount-ro).

This feels like a qemu-stable material.

Please let me know if it isn't.

Thanks,

/mjt

Signed-off-by: Li Chen <me@linux.beauty>
---
  hw/virtio/virtio-pmem.c | 1 -
  1 file changed, 1 deletion(-)

diff --git a/hw/virtio/virtio-pmem.c b/hw/virtio/virtio-pmem.c
index 3416ea1827..cec1072f78 100644
--- a/hw/virtio/virtio-pmem.c
+++ b/hw/virtio/virtio-pmem.c
@@ -74,7 +74,6 @@ static void virtio_pmem_flush(VirtIODevice *vdev, VirtQueue 
*vq)
      trace_virtio_pmem_flush_request();
      req_data = virtqueue_pop(vq, sizeof(VirtIODeviceRequest));
      if (!req_data) {
-        virtio_error(vdev, "virtio-pmem missing request data");
          return;
      }