virtio_ring: Fix error reporting in virtqueue_resize

The virtqueue_resize() function was not correctly propagating error codes
from its internal resize helper functions, specifically
virtqueue_resize_packet() and virtqueue_resize_split(). If these helpers
returned an error, but the subsequent call to virtqueue_enable_after_reset()
succeeded, the original error from the resize operation would be masked.
Consequently, virtqueue_resize() could incorrectly report success to its
caller despite an underlying resize failure.

This change restores the original code behavior:

       if (vdev->config->enable_vq_after_reset(_vq))
               return -EBUSY;

       return err;

Fix: commit ad48d53 ("virtio_ring: separate the logic of reset/enable from virtqueue_resize")
Cc: [email protected]
Signed-off-by: Laurent Vivier <[email protected]>
Acked-by: Jason Wang <[email protected]>
Link: https://patch.msgid.link/[email protected]
Tested-by: Lei Yang <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]>
Signed-off-by: Paolo Abeni <[email protected]>

Author: vivier

drivers/virtio/virtio_ring.c

@@ -2797,7 +2797,7 @@ int virtqueue_resize(struct virtqueue *_vq, u32 num,
 		     void (*recycle_done)(struct virtqueue *vq))
 {
 	struct vring_virtqueue *vq = to_vvq(_vq);
-	int err;
+	int err, err_reset;
 
 	if (num > vq->vq.num_max)
 		return -E2BIG;
@@ -2819,7 +2819,11 @@ int virtqueue_resize(struct virtqueue *_vq, u32 num,
 	else
 		err = virtqueue_resize_split(_vq, num);
 
-	return virtqueue_enable_after_reset(_vq);
+	err_reset = virtqueue_enable_after_reset(_vq);
+	if (err_reset)
+		return err_reset;
+
+	return err;
 }
 EXPORT_SYMBOL_GPL(virtqueue_resize);