This is a note to let you know that I've just added the patch titled
virtio_net: suppress cpu stall when free_unused_bufs
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
virtio_net-suppress-cpu-stall-when-free_unused_bufs.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a9ecd751d7d90f41c56621af0d76aa35a25950ef
Author: Wenliang Wang <wangwenliang.1995@xxxxxxxxxxxxx>
Date: Thu May 4 10:27:06 2023 +0800
virtio_net: suppress cpu stall when free_unused_bufs
[ Upstream commit f8bb5104394560e29017c25bcade4c6b7aabd108 ]
For multi-queue and large ring-size use case, the following error
occurred when free_unused_bufs:
rcu: INFO: rcu_sched self-detected stall on CPU.
Fixes: 986a4f4d452d ("virtio_net: multiqueue support")
Signed-off-by: Wenliang Wang <wangwenliang.1995@xxxxxxxxxxxxx>
Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 9b72b3f0b5bf9..d45e8de79f286 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -2685,12 +2685,14 @@ static void free_unused_bufs(struct virtnet_info *vi)
struct virtqueue *vq = vi->sq[i].vq;
while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
virtnet_sq_free_unused_buf(vq, buf);
+ cond_resched();
}
for (i = 0; i < vi->max_queue_pairs; i++) {
struct virtqueue *vq = vi->rq[i].vq;
while ((buf = virtqueue_detach_unused_buf(vq)) != NULL)
virtnet_rq_free_unused_buf(vq, buf);
+ cond_resched();
}
}
