aboutsummaryrefslogtreecommitdiffstats
path: root/fs/jbd
diff options
context:
space:
mode:
authorJan Kara <jack@suse.cz>2012-11-23 14:03:04 +0100
committerJan Kara <jack@suse.cz>2012-11-23 15:17:18 +0100
commit25389bb207987b5774182f763b9fb65ff08761c8 (patch)
tree84700b2e4697a4d51265e90b8b0ccac9e2ef485d /fs/jbd
parentext3: Avoid underflow of in ext3_trim_fs() (diff)
downloadlinux-dev-25389bb207987b5774182f763b9fb65ff08761c8.tar.xz
linux-dev-25389bb207987b5774182f763b9fb65ff08761c8.zip
jbd: Fix lock ordering bug in journal_unmap_buffer()
Commit 09e05d48 introduced a wait for transaction commit into journal_unmap_buffer() in the case we are truncating a buffer undergoing commit in the page stradding i_size on a filesystem with blocksize < pagesize. Sadly we forgot to drop buffer lock before waiting for transaction commit and thus deadlock is possible when kjournald wants to lock the buffer. Fix the problem by dropping the buffer lock before waiting for transaction commit. Since we are still holding page lock (and that is OK), buffer cannot disappear under us. CC: stable@vger.kernel.org # Wherever commit 09e05d48 was taken Signed-off-by: Jan Kara <jack@suse.cz>
Diffstat (limited to 'fs/jbd')
-rw-r--r--fs/jbd/transaction.c2
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
index 78b7f84241d4..7f5120bf0ec2 100644
--- a/fs/jbd/transaction.c
+++ b/fs/jbd/transaction.c
@@ -1961,7 +1961,9 @@ retry:
spin_unlock(&journal->j_list_lock);
jbd_unlock_bh_state(bh);
spin_unlock(&journal->j_state_lock);
+ unlock_buffer(bh);
log_wait_commit(journal, tid);
+ lock_buffer(bh);
goto retry;
}
/*