From 6db3c1575a750fd417a70e0178bdf6efa0dd5037 Mon Sep 17 00:00:00 2001 From: "Luis Henriques (SUSE)" Date: Wed, 17 Jul 2024 18:22:20 +0100 Subject: ext4: fix fast commit inode enqueueing during a full journal commit When a full journal commit is on-going, any fast commit has to be enqueued into a different queue: FC_Q_STAGING instead of FC_Q_MAIN. This enqueueing is done only once, i.e. if an inode is already queued in a previous fast commit entry it won't be enqueued again. However, if a full commit starts _after_ the inode is enqueued into FC_Q_MAIN, the next fast commit needs to be done into FC_Q_STAGING. And this is not being done in function ext4_fc_track_template(). This patch fixes the issue by re-enqueuing an inode into the STAGING queue during the fast commit clean-up callback when doing a full commit. However, to prevent a race with a fast-commit, the clean-up callback has to be called with the journal locked. This bug was found using fstest generic/047. This test creates several 32k bytes files, sync'ing each of them after it's creation, and then shutting down the filesystem. Some data may be loss in this operation; for example a file may have it's size truncated to zero. Suggested-by: Jan Kara Signed-off-by: Luis Henriques (SUSE) Reviewed-by: Jan Kara Link: https://patch.msgid.link/20240717172220.14201-1-luis.henriques@linux.dev Signed-off-by: Theodore Ts'o Cc: stable@kernel.org --- fs/jbd2/journal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/jbd2') diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 1ebf2393bfb7..291a431f8aaf 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -740,9 +740,9 @@ EXPORT_SYMBOL(jbd2_fc_begin_commit); */ static int __jbd2_fc_end_commit(journal_t *journal, tid_t tid, bool fallback) { - jbd2_journal_unlock_updates(journal); if (journal->j_fc_cleanup_callback) journal->j_fc_cleanup_callback(journal, 0, tid); + jbd2_journal_unlock_updates(journal); write_lock(&journal->j_state_lock); journal->j_flags &= ~JBD2_FAST_COMMIT_ONGOING; if (fallback) -- cgit v1.2.3