summaryrefslogtreecommitdiffstats
path: root/block
diff options
context:
space:
mode:
authorHanna Reitz2022-11-07 16:13:20 +0100
committerKevin Wolf2022-11-10 14:58:38 +0100
commitaf5b6ebe5b887cb650434f9f7294af597a66314c (patch)
tree5c468bf31fc9e7fd418d03cf8b2b46e8cb084940 /block
parentblock: Make bdrv_child_get_parent_aio_context I/O (diff)
downloadqemu-af5b6ebe5b887cb650434f9f7294af597a66314c.tar.gz
qemu-af5b6ebe5b887cb650434f9f7294af597a66314c.tar.xz
qemu-af5b6ebe5b887cb650434f9f7294af597a66314c.zip
block-backend: Update ctx immediately after root
blk_get_aio_context() asserts that blk->ctx is always equal to the root BDS's context (if there is a root BDS). Therefore, blk_do_set_aio_context() must update blk->ctx immediately after the root BDS's context has changed. Without this patch, the next patch would break iotest 238, because bdrv_drained_begin() (called by blk_do_set_aio_context()) may then invoke bdrv_child_get_parent_aio_context() on the root child, i.e. blk_get_aio_context(). However, by this point, blk->ctx would not have been updated and thus differ from the root node's context. This patch fixes that. Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221107151321.211175-3-hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block')
-rw-r--r--block/block-backend.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/block/block-backend.c b/block/block-backend.c
index ed2f4b67a2..b48c91f4e1 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -2158,6 +2158,11 @@ static int blk_do_set_aio_context(BlockBackend *blk, AioContext *new_context,
return ret;
}
}
+ /*
+ * Make blk->ctx consistent with the root node before we invoke any
+ * other operations like drain that might inquire blk->ctx
+ */
+ blk->ctx = new_context;
if (tgm->throttle_state) {
bdrv_drained_begin(bs);
throttle_group_detach_aio_context(tgm);
@@ -2166,9 +2171,10 @@ static int blk_do_set_aio_context(BlockBackend *blk, AioContext *new_context,
}
bdrv_unref(bs);
+ } else {
+ blk->ctx = new_context;
}
- blk->ctx = new_context;
return 0;
}