From: Jan Kara Date: Wed, 5 Dec 2012 13:40:14 +0000 (+0100) Subject: fs: Fix imbalance in freeze protection in mark_files_ro() X-Git-Tag: firefly_0821_release~3680^2~1354^2~52 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=72651cac884b1e285fa8e8314b10e9f1b8458802;p=firefly-linux-kernel-4.4.55.git fs: Fix imbalance in freeze protection in mark_files_ro() File descriptors (even those for writing) do not hold freeze protection. Thus mark_files_ro() must call __mnt_drop_write() to only drop protection against remount read-only. Calling mnt_drop_write_file() as we do now results in: [ BUG: bad unlock balance detected! ] 3.7.0-rc6-00028-g88e75b6 #101 Not tainted ------------------------------------- kworker/1:2/79 is trying to release lock (sb_writers) at: [] mnt_drop_write+0x24/0x30 but there are no more locks to release! Reported-by: Zdenek Kabelac CC: stable@vger.kernel.org Signed-off-by: Jan Kara Signed-off-by: Al Viro --- diff --git a/fs/file_table.c b/fs/file_table.c index a72bf9ddd0d2..de9e9653d611 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -458,8 +458,8 @@ void mark_files_ro(struct super_block *sb) spin_unlock(&f->f_lock); if (file_check_writeable(f) != 0) continue; + __mnt_drop_write(f->f_path.mnt); file_release_write(f); - mnt_drop_write_file(f); } while_file_list_for_each_entry; lg_global_unlock(&files_lglock); }