On 2025/2/6 17:46, Jan Kara wrote:
> If a journal is wiped, we will set journal->j_tail to 0. However if
> 'write' argument is not set (as it happens for read-only device or for
> ocfs2), the on-disk superblock is not updated accordingly and thus
> jbd2_journal_recover() cat try to recover the wiped journal. Fix the
> check in jbd2_journal_recover() to use journal->j_tail for checking
> empty journal instead.
>
> Signed-off-by: Jan Kara <jack@xxxxxxx>
Ha, right, it looks good to me.
Reviewed-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
> ---
> fs/jbd2/recovery.c | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c
> index 9192be7c19d8..23502f1a67c1 100644
> --- a/fs/jbd2/recovery.c
> +++ b/fs/jbd2/recovery.c
> @@ -287,19 +287,20 @@ static int fc_do_one_pass(journal_t *journal,
> int jbd2_journal_recover(journal_t *journal)
> {
> int err, err2;
> - journal_superblock_t * sb;
> -
> struct recovery_info info;
>
> memset(&info, 0, sizeof(info));
> - sb = journal->j_superblock;
>
> /*
> * The journal superblock's s_start field (the current log head)
> * is always zero if, and only if, the journal was cleanly
> - * unmounted.
> + * unmounted. We use its in-memory version j_tail here because
> + * jbd2_journal_wipe() could have updated it without updating journal
> + * superblock.
> */
> - if (!sb->s_start) {
> + if (!journal->j_tail) {
> + journal_superblock_t *sb = journal->j_superblock;
> +
> jbd2_debug(1, "No recovery required, last transaction %d, head block %u\n",
> be32_to_cpu(sb->s_sequence), be32_to_cpu(sb->s_head));
> journal->j_transaction_sequence = be32_to_cpu(sb->s_sequence) + 1;
