When we're enabling journal features, we cannot use the predicate jbd2_journal_has_csum_v2or3() because we haven't yet set the sb feature flag fields! Moreover, we just finished loading the shash driver, so the test is unnecessary; calculate the seed always. Without this patch, we fail to initialize the checksum seed the first time we turn on journal_checksum, which means that all journal blocks written during that first mount are corrupt. Transactions written after the second mount will be fine, since the feature flag will be set in the journal superblock. xfstests generic/{034,321,322} are the regression tests. (This is important for 3.18.) Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Reported-by: Eric Whitney <enwlinux@xxxxxxxxx> --- fs/jbd2/journal.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index e4dc747..1df94fa 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -1853,13 +1853,12 @@ int jbd2_journal_set_features (journal_t *journal, unsigned long compat, journal->j_chksum_driver = NULL; return 0; } - } - /* Precompute checksum seed for all metadata */ - if (jbd2_journal_has_csum_v2or3(journal)) + /* Precompute checksum seed for all metadata */ journal->j_csum_seed = jbd2_chksum(journal, ~0, sb->s_uuid, sizeof(sb->s_uuid)); + } } /* If enabling v1 checksums, downgrade superblock */ -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html