The patch below does not apply to the 3.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 2e84f2641ea91a730642ead558a4ee3bd52310c9 Mon Sep 17 00:00:00 2001 From: Jan Kara <[email protected]> Date: Wed, 15 Aug 2012 13:50:27 +0200 Subject: [PATCH] jbd: don't write superblock when unmounting an ro filesystem This sequence: results in an IO error when unmounting the RO filesystem. The bug was introduced by: commit 9754e39c7bc51328f145e933bfb0df47cd67b6e9 Author: Jan Kara <[email protected]> Date: Sat Apr 7 12:33:03 2012 +0200 jbd: Split updating of journal superblock and marking journal empty which lost some of the magic in journal_update_superblock() which used to test for a journal with no outstanding transactions. This is a port of a jbd2 fix by Eric Sandeen. CC: <[email protected]> # 3.4.x Signed-off-by: Jan Kara <[email protected]> diff --git a/fs/jbd/journal.c b/fs/jbd/journal.c index 0935750..a286233 100644 --- a/fs/jbd/journal.c +++ b/fs/jbd/journal.c @@ -1113,6 +1113,11 @@ static void mark_journal_empty(journal_t *journal) BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); spin_lock(&journal->j_state_lock); + /* Is it already empty? */ + if (sb->s_start == 0) { + spin_unlock(&journal->j_state_lock); + return; + } jbd_debug(1, "JBD: Marking journal as empty (seq %d)\n", journal->j_tail_sequence); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
