This is a note to let you know that I've just added the patch titled
ext4: annotate data race in jbd2_journal_dirty_metadata()
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ext4-annotate-data-race-in-jbd2_journal_dirty_metadata.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 83fe6b18b8d04c6c849379005e1679bac9752466 Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@xxxxxxx>
Date: Tue, 6 Apr 2021 18:18:00 +0200
Subject: ext4: annotate data race in jbd2_journal_dirty_metadata()
From: Jan Kara <jack@xxxxxxx>
commit 83fe6b18b8d04c6c849379005e1679bac9752466 upstream.
Assertion checks in jbd2_journal_dirty_metadata() are known to be racy
but we don't want to be grabbing locks just for them. We thus recheck
them under b_state_lock only if it looks like they would fail. Annotate
the checks with data_race().
Cc: stable@xxxxxxxxxx
Reported-by: Hao Sun <sunhao.th@xxxxxxxxx>
Signed-off-by: Jan Kara <jack@xxxxxxx>
Link: https://lore.kernel.org/r/20210406161804.20150-2-jack@xxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/jbd2/transaction.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -1479,8 +1479,8 @@ int jbd2_journal_dirty_metadata(handle_t
* crucial to catch bugs so let's do a reliable check until the
* lockless handling is fully proven.
*/
- if (jh->b_transaction != transaction &&
- jh->b_next_transaction != transaction) {
+ if (data_race(jh->b_transaction != transaction &&
+ jh->b_next_transaction != transaction)) {
spin_lock(&jh->b_state_lock);
J_ASSERT_JH(jh, jh->b_transaction == transaction ||
jh->b_next_transaction == transaction);
@@ -1488,8 +1488,8 @@ int jbd2_journal_dirty_metadata(handle_t
}
if (jh->b_modified == 1) {
/* If it's in our transaction it must be in BJ_Metadata list. */
- if (jh->b_transaction == transaction &&
- jh->b_jlist != BJ_Metadata) {
+ if (data_race(jh->b_transaction == transaction &&
+ jh->b_jlist != BJ_Metadata)) {
spin_lock(&jh->b_state_lock);
if (jh->b_transaction == transaction &&
jh->b_jlist != BJ_Metadata)
Patches currently in stable-queue which might be from jack@xxxxxxx are
queue-5.10/ext4-fix-occasional-generic-418-failure.patch
queue-5.10/ext4-do-not-set-sb_active-in-ext4_orphan_cleanup.patch
queue-5.10/ext4-annotate-data-race-in-start_this_handle.patch
queue-5.10/ext4-fix-check-to-prevent-false-positive-report-of-incorrect-used-inodes.patch
queue-5.10/ext4-annotate-data-race-in-jbd2_journal_dirty_metadata.patch
