On Thu, Jan 30, 2025 at 02:17:44AM +0900, Jeongjun Park wrote:
> In the previous commit b3d82c2f2761, code was added to prevent journal
> sequence
> overflow. Among them, the code added to journal_entry_open() uses the
> bch2_fs_fatal_err_on() function to handle errors.
>
> However, __journal_res_get() , which calls journal_entry_open() , calls
> journal_entry_open() while holding journal->lock , but bch2_fs_fatal_err_on()
> internally tries to acquire journal->lock , which results in a deadlock.
>
> Therefore, we need to use bch_err() instead of bch2_fs_fatal_err_on() to
> prevent deadlock.
We do the emergency shutdown though...
Perhaps add a bch2_journal_halt_locked() helper?
> Fixes: b3d82c2f2761 ("bcachefs: Guard against journal seq overflow")
> Signed-off-by: Jeongjun Park <[email protected]>
> ---
> fs/bcachefs/journal.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/fs/bcachefs/journal.c b/fs/bcachefs/journal.c
> index 2cd20114b74b..38ba5ab785c3 100644
> --- a/fs/bcachefs/journal.c
> +++ b/fs/bcachefs/journal.c
> @@ -382,9 +382,10 @@ static int journal_entry_open(struct journal *j)
> if (nr_unwritten_journal_entries(j) == ARRAY_SIZE(j->buf))
> return JOURNAL_ERR_max_in_flight;
>
> - if (bch2_fs_fatal_err_on(journal_cur_seq(j) >= JOURNAL_SEQ_MAX,
> - c, "cannot start: journal seq overflow"))
> + if (journal_cur_seq(j) >= JOURNAL_SEQ_MAX) {
> + bch_err(c, "cannot start: journal seq overflow");
> return JOURNAL_ERR_insufficient_devices; /* -EROFS */
> + }
>
> BUG_ON(!j->cur_entry_sectors);
>
> --
