kernel.git/fs/jbd2/journal.c, branch linux-rolling-stable

jbd2: fix the inconsistency between checksum and data in memory for journal sb

2025-11-26T22:05:47Z

Copying the file system while it is mounted as read-only results in a mount failure: [~]# mkfs.ext4 -F /dev/sdc [~]# mount /dev/sdc -o ro /mnt/test [~]# dd if=/dev/sdc of=/dev/sda bs=1M [~]# mount /dev/sda /mnt/test1 [ 1094.849826] JBD2: journal checksum error [ 1094.850927] EXT4-fs (sda): Could not load journal inode mount: mount /dev/sda on /mnt/test1 failed: Bad message The process described above is just an abstracted way I came up with to reproduce the issue. In the actual scenario, the file system was mounted read-only and then copied while it was still mounted. It was found that the mount operation failed. The user intended to verify the data or use it as a backup, and this action was performed during a version upgrade. Above issue may happen as follows: ext4_fill_super set_journal_csum_feature_set(sb) if (ext4_has_metadata_csum(sb)) incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3; if (test_opt(sb, JOURNAL_CHECKSUM) jbd2_journal_set_features(sbi->s_journal, compat, 0, incompat); lock_buffer(journal->j_sb_buffer); sb->s_feature_incompat |= cpu_to_be32(incompat); //The data in the journal sb was modified, but the checksum was not updated, so the data remaining in memory has a mismatch between the data and the checksum. unlock_buffer(journal->j_sb_buffer); In this case, the journal sb copied over is in a state where the checksum and data are inconsistent, so mounting fails. To solve the above issue, update the checksum in memory after modifying the journal sb. Fixes: 4fd5ea43bc11 ("jbd2: checksum journal superblock") Signed-off-by: Ye Bin Reviewed-by: Baokun Li Reviewed-by: Darrick J. Wong Reviewed-by: Jan Kara Message-ID: <20251103010123.3753631-1-yebin@huaweicloud.com> Signed-off-by: Theodore Ts'o Cc: stable@kernel.org

jbd2: store more accurate errno in superblock when possible

2025-11-26T22:05:39Z

When jbd2_journal_abort() is called, the provided error code is stored in the journal superblock. Some existing calls hard-code -EIO even when the actual failure is not I/O related. This patch updates those calls to pass more accurate error codes, allowing the superblock to record the true cause of failure. This helps improve diagnostics and debugging clarity when analyzing journal aborts. Signed-off-by: Wengang Wang Reviewed-by: Zhang Yi Message-ID: <20251031210501.7337-1-wen.gang.wang@oracle.com> Signed-off-by: Theodore Ts'o

jbd2: use a per-journal lock_class_key for jbd2_trans_commit_key

2025-11-13T13:34:39Z

syzbot is reporting possibility of deadlock due to sharing lock_class_key for jbd2_handle across ext4 and ocfs2. But this is a false positive, for one disk partition can't have two filesystems at the same time. Reported-by: syzbot+6e493c165d26d6fcbf72@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=6e493c165d26d6fcbf72 Signed-off-by: Tetsuo Handa Tested-by: syzbot+6e493c165d26d6fcbf72@syzkaller.appspotmail.com Reviewed-by: Jan Kara Message-ID: <987110fc-5470-457a-a218-d286a09dd82f@I-love.SAKURA.ne.jp> Signed-off-by: Theodore Ts'o Cc: stable@kernel.org

treewide, timers: Rename from_timer() to timer_container_of()

2025-06-08T07:07:37Z

Move this API to the canonical timer_*() namespace. [ tglx: Redone against pre rc1 ] Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com

jbd2: remove journal_t argument from jbd2_superblock_csum()

2025-05-20T14:31:12Z

Since jbd2_superblock_csum() no longer uses its journal_t argument, remove it. Signed-off-by: Eric Biggers Reviewed-by: Baokun Li Link: https://patch.msgid.link/20250513053809.699974-5-ebiggers@kernel.org Signed-off-by: Theodore Ts'o

jbd2: remove journal_t argument from jbd2_chksum()

2025-05-20T14:31:12Z

Since jbd2_chksum() no longer uses its journal_t argument, remove it. Signed-off-by: Eric Biggers Reviewed-by: Baokun Li Link: https://patch.msgid.link/20250513053809.699974-4-ebiggers@kernel.org Signed-off-by: Theodore Ts'o

ext4/jbd2: convert jbd2_journal_blocks_per_page() to support large folio

2025-05-20T14:31:12Z

jbd2_journal_blocks_per_page() returns the number of blocks in a single page. Rename it to jbd2_journal_blocks_per_folio() and make it returns the number of blocks in the largest folio, preparing for the calculation of journal credits blocks when allocating blocks within a large folio in the writeback path. Signed-off-by: Zhang Yi Link: https://patch.msgid.link/20250512063319.3539411-5-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o

ext4: rework fast commit commit path

2025-05-09T01:56:17Z

This patch reworks fast commit's commit path to remove locking the journal for the entire duration of a fast commit. Instead, we only lock the journal while marking all the eligible inodes as "committing". This allows handles to make progress in parallel with the fast commit. Signed-off-by: Harshad Shirwadkar Link: https://patch.msgid.link/20250508175908.1004880-5-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o

treewide: Switch/rename to timer_delete[_sync]()

2025-04-05T08:30:12Z

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar

jbd2: add a missing data flush during file and fs synchronization

2025-03-21T04:59:28Z

When the filesystem performs file or filesystem synchronization (e.g., ext4_sync_file()), it queries the journal to determine whether to flush the file device through jbd2_trans_will_send_data_barrier(). If the target transaction has not started committing, it assumes that the journal will submit the flush command, allowing the filesystem to bypass a redundant flush command. However, this assumption is not always valid. If the journal is not located on the filesystem device, the journal commit thread will not submit the flush command unless the variable ->t_need_data_flush is set to 1. Consequently, the flush may be missed, and data may be lost following a power failure or system crash, even if the synchronization appears to succeed. Unfortunately, we cannot determine with certainty whether the target transaction will flush to the filesystem device before it commits. However, if it has not started committing, it must be the running transaction. Therefore, fix it by always set its t_need_data_flush to 1, ensuring that the committing thread will flush the filesystem device. Fixes: bbd2be369107 ("jbd2: Add function jbd2_trans_will_send_data_barrier()") Signed-off-by: Zhang Yi Reviewed-by: Jan Kara Link: https://patch.msgid.link/20241206111327.4171337-1-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o