From 004d500df234e5a093c16f36fc084b093a4d9744 Mon Sep 17 00:00:00 2001 From: Mark Johnston Date: Fri, 25 Oct 2024 17:52:22 +0000 Subject: [PATCH] virtio_p9fs: Check for completions after enabling interrupts Otherwise we can end up with a lost interrupt, causing lost request completion wakeups and hangs in the filesystem layer. Continue processing until we enable interrupts and then observe an empty queue, like other virtio drivers do. Sponsored by: Klara, Inc. --- sys/dev/virtio/p9fs/virtio_p9fs.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/sys/dev/virtio/p9fs/virtio_p9fs.c b/sys/dev/virtio/p9fs/virtio_p9fs.c index 67426a88bce..24d4542e4e4 100644 --- a/sys/dev/virtio/p9fs/virtio_p9fs.c +++ b/sys/dev/virtio/p9fs/virtio_p9fs.c @@ -222,11 +222,15 @@ vt9p_intr_complete(void *xsc) P9_DEBUG(TRANS, "%s: completing\n", __func__); VT9P_LOCK(chan); +again: while ((curreq = virtqueue_dequeue(vq, NULL)) != NULL) { curreq->rc->tag = curreq->tc->tag; wakeup_one(curreq); } - virtqueue_enable_intr(vq); + if (virtqueue_enable_intr(vq) != 0) { + virtqueue_disable_intr(vq); + goto again; + } cv_signal(&chan->submit_cv); VT9P_UNLOCK(chan); }