From: Stefan Hajnoczi <stefa...@redhat.com> Calling aio_poll() directly may have been fine previously, but this is the future, man! The difference between an aio_poll() loop and BDRV_POLL_WHILE() is that BDRV_POLL_WHILE() releases the AioContext around aio_poll().
This allows the IOThread to run fd handlers or BHs to complete the request. Failure to release the AioContext causes deadlocks. Using BDRV_POLL_WHILE() partially fixes a 'savevm' hang with -object iothread. Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com> Reviewed-by: Eric Blake <ebl...@redhat.com> Reviewed-by: Paolo Bonzini <pbonz...@redhat.com> Signed-off-by: Kevin Wolf <kw...@redhat.com> --- block/io.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/block/io.c b/block/io.c index 684ea46..e158ae0 100644 --- a/block/io.c +++ b/block/io.c @@ -2023,9 +2023,7 @@ bdrv_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos, Coroutine *co = qemu_coroutine_create(bdrv_co_rw_vmstate_entry, &data); bdrv_coroutine_enter(bs, co); - while (data.ret == -EINPROGRESS) { - aio_poll(bdrv_get_aio_context(bs), true); - } + BDRV_POLL_WHILE(bs, data.ret == -EINPROGRESS); return data.ret; } } -- 1.8.3.1