From d4da6c9ccf648f3f1cb5bf9d981a62c253d30e28 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 2 Nov 2009 10:15:27 -0800 Subject: Revert "ext4: Remove journal_checksum mount option and enable it by default" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This reverts commit d0646f7b636d067d715fab52a2ba9c6f0f46b0d7, as requested by Eric Sandeen. It can basically cause an ext4 filesystem to miss recovery (and thus get mounted with errors) if the journal checksum does not match. Quoth Eric: "My hand-wavy hunch about what is happening is that we're finding a bad checksum on the last partially-written transaction, which is not surprising, but if we have a wrapped log and we're doing the initial scan for head/tail, and we abort scanning on that bad checksum, then we are essentially running an unrecovered filesystem. But that's hand-wavy and I need to go look at the code. We lived without journal checksums on by default until now, and at this point they're doing more harm than good, so we should revert the default-changing commit until we can fix it and do some good power-fail testing with the fixes in place." See http://bugzilla.kernel.org/show_bug.cgi?id=14354 for all the gory details. Requested-by: Eric Sandeen Cc: Theodore Tso Cc: Alexey Fisher Cc: Maxim Levitsky Cc: Aneesh Kumar K.V Cc: Mathias Burén Signed-off-by: Linus Torvalds --- fs/ext4/super.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 312211ee05a..d4ca92aab51 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1300,9 +1300,11 @@ static int parse_options(char *options, struct super_block *sb, *journal_devnum = option; break; case Opt_journal_checksum: - break; /* Kept for backwards compatibility */ + set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM); + break; case Opt_journal_async_commit: set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT); + set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM); break; case Opt_noload: set_opt(sbi->s_mount_opt, NOLOAD); @@ -2759,14 +2761,20 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto failed_mount4; } - jbd2_journal_set_features(sbi->s_journal, - JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0); - if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) - jbd2_journal_set_features(sbi->s_journal, 0, 0, + if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) { + jbd2_journal_set_features(sbi->s_journal, + JBD2_FEATURE_COMPAT_CHECKSUM, 0, JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT); - else + } else if (test_opt(sb, JOURNAL_CHECKSUM)) { + jbd2_journal_set_features(sbi->s_journal, + JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0); jbd2_journal_clear_features(sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT); + } else { + jbd2_journal_clear_features(sbi->s_journal, + JBD2_FEATURE_COMPAT_CHECKSUM, 0, + JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT); + } /* We have now updated the journal if required, so we can * validate the data journaling mode. */ -- cgit v1.2.3