sysfs: Take sysfs_mutex when fetching the root inode.

sysfs_get_inode ultimately calls sysfs_count_nlink when the a
directory inode is fectched.  sysfs_count_nlink needs to be
called under the sysfs_mutex to guard against the unlikely
but possible scenario that the root directory is changing
as we are counting the number entries in it, and just in
general to be consistent.

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Eric W. Biederman 2009-01-21 11:55:11 -08:00 committed by Greg Kroah-Hartman
parent 8231f2f99a
commit 4a67a1bc0b

View File

@ -52,7 +52,9 @@ static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
sysfs_sb = sb;
/* get root inode, initialize and unlock it */
mutex_lock(&sysfs_mutex);
inode = sysfs_get_inode(&sysfs_root);
mutex_unlock(&sysfs_mutex);
if (!inode) {
pr_debug("sysfs: could not get root inode\n");
return -ENOMEM;