For a fifo read pattern, we only have one running aio (possible other cases that has less number than num_children in the future), so we need to check if .acb is NULL against bdrv_aio_cancel() to avoid segfault.
Cc: Eric Blake <ebl...@redhat.com> Cc: Benoit Canet <ben...@irqsave.net> Cc: Kevin Wolf <kw...@redhat.com> Cc: Stefan Hajnoczi <stefa...@redhat.com> Signed-off-by: Liu Yuan <namei.u...@gmail.com> --- block/quorum.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/block/quorum.c b/block/quorum.c index 9e056d6..b9eeda3 100644 --- a/block/quorum.c +++ b/block/quorum.c @@ -144,7 +144,9 @@ static void quorum_aio_cancel(BlockDriverAIOCB *blockacb) /* cancel all callbacks */ for (i = 0; i < s->num_children; i++) { - bdrv_aio_cancel(acb->qcrs[i].aiocb); + if (acb->qcrs[i].aiocb) { + bdrv_aio_cancel(acb->qcrs[i].aiocb); + } } quorum_aio_release(acb); -- 1.9.1