From: Halil Pasic <pasic@xxxxxxxxxxxxx>
commit f7728002c1c7bfa787b276a31c3ef458739b8e7c upstream.
Commit 780bc7903a32 ("virtio_ring: Support DMA APIs") makes
virtqueue_add() return -EIO when we fail to map our I/O buffers. This is
a very realistic scenario for guests with encrypted memory, as swiotlb
may run out of space, depending on it's size and the I/O load.
The virtio-blk driver interprets -EIO form virtqueue_add() as an IO
error, despite the fact that swiotlb full is in absence of bugs a
recoverable condition.
Let us change the return code to -ENOMEM, and make the block layer
recover form these failures when virtio-blk encounters the condition
described above.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 780bc7903a32 ("virtio_ring: Support DMA APIs")
Signed-off-by: Halil Pasic <pasic@xxxxxxxxxxxxx>
Tested-by: Michael Mueller <mimu@xxxxxxxxxxxxx>
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/virtio/virtio_ring.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -583,7 +583,7 @@ unmap_release:
kfree(desc);
END_USE(vq);
- return -EIO;
+ return -ENOMEM;
}
static bool virtqueue_kick_prepare_split(struct virtqueue *_vq)
@@ -1085,7 +1085,7 @@ unmap_release:
kfree(desc);
END_USE(vq);
- return -EIO;
+ return -ENOMEM;
}
static inline int virtqueue_add_packed(struct virtqueue *_vq,
