GFS2: don't hold s_umount over blkdev_put

This is a GFS2 version of Tejun's patch:
4f331f01b9
vfs: don't hold s_umount over close_bdev_exclusive() call

In this case its blkdev_put itself that is the issue and this
patch uses the same solution of dropping and retaking s_umount.

Reported-by: Tejun Heo <tj@kernel.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This commit is contained in:
Steven Whitehouse 2013-12-06 11:52:34 +00:00
Родитель 7e3528c366
Коммит dfe5b9ad83
1 изменённых файлов: 11 добавлений и 1 удалений

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@ -1366,8 +1366,18 @@ static struct dentry *gfs2_mount(struct file_system_type *fs_type, int flags,
if (IS_ERR(s))
goto error_bdev;
if (s->s_root)
if (s->s_root) {
/*
* s_umount nests inside bd_mutex during
* __invalidate_device(). blkdev_put() acquires
* bd_mutex and can't be called under s_umount. Drop
* s_umount temporarily. This is safe as we're
* holding an active reference.
*/
up_write(&s->s_umount);
blkdev_put(bdev, mode);
down_write(&s->s_umount);
}
memset(&args, 0, sizeof(args));
args.ar_quota = GFS2_QUOTA_DEFAULT;