diff options
| author | Stefan Hajnoczi <stefanha@redhat.com> | 2017-12-06 14:45:42 +0000 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2017-12-19 10:25:08 +0000 |
| commit | b9464ba19f821ea6b29969104dc48dcdb26243dd (patch) | |
| tree | 1b22c15c586163144df54fce1f81199a62f33fae /blockdev.c | |
| parent | a12aef24fa3e3312fac024ac22809ee9deb4d98a (diff) | |
| download | qemu-b9464ba19f821ea6b29969104dc48dcdb26243dd.tar.gz | |
blockdev: hold AioContext for bdrv_unref() in external_snapshot_clean()
bdrv_unref() requires the AioContext lock because bdrv_flush() uses
BDRV_POLL_WHILE(), which assumes the AioContext is currently held. If
BDRV_POLL_WHILE() runs without AioContext held the
pthread_mutex_unlock() call in aio_context_release() fails.
This patch moves bdrv_unref() into the AioContext locked region to solve
the following pthread_mutex_unlock() failure:
#0 0x00007f566181969b in raise () at /lib64/libc.so.6
#1 0x00007f566181b3b1 in abort () at /lib64/libc.so.6
#2 0x00005592cd590458 in error_exit (err=<optimized out>, msg=msg@entry=0x5592cdaf6d60 <__func__.23977> "qemu_mutex_unlock") at util/qemu-thread-posix.c:36
#3 0x00005592cd96e738 in qemu_mutex_unlock (mutex=mutex@entry=0x5592ce9505e0) at util/qemu-thread-posix.c:96
#4 0x00005592cd969b69 in aio_context_release (ctx=ctx@entry=0x5592ce950580) at util/async.c:507
#5 0x00005592cd8ead78 in bdrv_flush (bs=bs@entry=0x5592cfa87210) at block/io.c:2478
#6 0x00005592cd89df30 in bdrv_close (bs=0x5592cfa87210) at block.c:3207
#7 0x00005592cd89df30 in bdrv_delete (bs=0x5592cfa87210) at block.c:3395
#8 0x00005592cd89df30 in bdrv_unref (bs=0x5592cfa87210) at block.c:4418
#9 0x00005592cd6b7f86 in qmp_transaction (dev_list=<optimized out>, has_props=<optimized out>, props=<optimized out>, errp=errp@entry=0x7ffe4a1fc9d8) at blockdev.c:2308
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171206144550.22295-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'blockdev.c')
| -rw-r--r-- | blockdev.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/blockdev.c b/blockdev.c index 56a6b24a0b..3c8d994ced 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1812,8 +1812,8 @@ static void external_snapshot_clean(BlkActionState *common) DO_UPCAST(ExternalSnapshotState, common, common); if (state->aio_context) { bdrv_drained_end(state->old_bs); - aio_context_release(state->aio_context); bdrv_unref(state->new_bs); + aio_context_release(state->aio_context); } } |