If scheduling fails, the number of outstanding I/Os must be correct, or there will be a hang when waiting for everything to be flushed. Reported-by: Stefan Hajnoczi <stefanha@xxxxxxxxx> Signed-off-by: Josh Durgin <josh.durgin@xxxxxxxxxxxxx> --- block/rbd.c | 24 ++++++++++++++++++++---- 1 files changed, 20 insertions(+), 4 deletions(-) diff --git a/block/rbd.c b/block/rbd.c index ff74e8b..c9f32e4 100644 --- a/block/rbd.c +++ b/block/rbd.c @@ -580,10 +580,14 @@ static BlockDriverAIOCB *rbd_aio_rw_vector(BlockDriverState *bs, rbd_completion_t c; int64_t off, size; char *buf; + int r; BDRVRBDState *s = bs->opaque; acb = qemu_aio_get(&rbd_aio_pool, bs, cb, opaque); + if (!acb) { + return NULL; + } acb->write = write; acb->qiov = qiov; acb->bounce = qemu_blockalign(bs, qiov->size); @@ -610,16 +614,28 @@ static BlockDriverAIOCB *rbd_aio_rw_vector(BlockDriverState *bs, rcb->buf = buf; rcb->s = acb->s; rcb->size = size; + r = rbd_aio_create_completion(rcb, (rbd_callback_t) rbd_finish_aiocb, &c); + if (r < 0) { + goto failed; + } if (write) { - rbd_aio_create_completion(rcb, (rbd_callback_t) rbd_finish_aiocb, &c); - rbd_aio_write(s->image, off, size, buf, c); + r = rbd_aio_write(s->image, off, size, buf, c); } else { - rbd_aio_create_completion(rcb, (rbd_callback_t) rbd_finish_aiocb, &c); - rbd_aio_read(s->image, off, size, buf, c); + r = rbd_aio_read(s->image, off, size, buf, c); + } + + if (r < 0) { + goto failed; } return &acb->common; + +failed: + qemu_free(rcb); + s->qemu_aio_count--; + qemu_aio_release(acb); + return NULL; } static BlockDriverAIOCB *qemu_rbd_aio_readv(BlockDriverState *bs, -- 1.7.2.3 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html