block: Fix locking in media change monitor commands

blk_insert_bs() requires that the caller holds the AioContext lock for
the node to be inserted. Since commit c066e808e1, neglecting to do so
causes a crash when the child has to be moved to a different AioContext
to attach it to the BlockBackend.

This fixes qmp_blockdev_insert_anon_medium(), which is called for the
QMP commands 'blockdev-insert-medium' and 'blockdev-change-medium', to
correctly take the lock.

Cc: qemu-stable@nongnu.org
Fixes: https://issues.redhat.com/browse/RHEL-3922
Fixes: c066e808e1
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231013153302.39234-2-kwolf@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit fed8245015)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This commit is contained in:
Kevin Wolf 2023-10-13 17:33:01 +02:00 committed by Michael Tokarev
parent b938418f0d
commit 3a2d501916

View File

@ -232,6 +232,7 @@ static void qmp_blockdev_insert_anon_medium(BlockBackend *blk,
BlockDriverState *bs, Error **errp)
{
Error *local_err = NULL;
AioContext *ctx;
bool has_device;
int ret;
@ -253,7 +254,11 @@ static void qmp_blockdev_insert_anon_medium(BlockBackend *blk,
return;
}
ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
ret = blk_insert_bs(blk, bs, errp);
aio_context_release(ctx);
if (ret < 0) {
return;
}