From: Kevin Wolf <kwolf@redhat.com>
Date: Thu, 25 May 2023 12:47:06 +0000 (+0200)
Subject: mirror: Hold main AioContext lock for calling bdrv_open_backing_file()
X-Git-Tag: v8.1.0-rc0~87^2~27
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=2626d27f50f3c993936db04bc6e92d553e1dc914;p=thirdparty%2Fqemu.git

mirror: Hold main AioContext lock for calling bdrv_open_backing_file()

bdrv_open_backing_file() calls bdrv_open_inherit(), so all callers must
hold the main AioContext lock.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230525124713.401149-6-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---

diff --git a/block.c b/block.c
index 79bc9c01de0..be9ae364fbe 100644
--- a/block.c
+++ b/block.c
@@ -3478,6 +3478,8 @@ int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd,
  * itself, all options starting with "${bdref_key}." are considered part of the
  * BlockdevRef.
  *
+ * The caller must hold the main AioContext lock.
+ *
  * TODO Can this be unified with bdrv_open_image()?
  */
 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options,
diff --git a/block/mirror.c b/block/mirror.c
index b7d92d13786..d3cacd17086 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -662,11 +662,15 @@ static int mirror_exit_common(Job *job)
     bool abort = job->ret < 0;
     int ret = 0;
 
+    GLOBAL_STATE_CODE();
+
     if (s->prepared) {
         return 0;
     }
     s->prepared = true;
 
+    aio_context_acquire(qemu_get_aio_context());
+
     mirror_top_bs = s->mirror_top_bs;
     bs_opaque = mirror_top_bs->opaque;
     src = mirror_top_bs->backing->bs;
@@ -789,6 +793,8 @@ static int mirror_exit_common(Job *job)
     bdrv_unref(mirror_top_bs);
     bdrv_unref(src);
 
+    aio_context_release(qemu_get_aio_context());
+
     return ret;
 }