ext4 does not permit changing the metadata or journal checksum feature flag while mounted. Until we decide to support that, don't allow a remount to change the journal_csum flag (right now we silently fail to change anything). Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- fs/ext4/super.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 5c11e21..96059e0 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4845,6 +4845,14 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) goto restore_opts; } + if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^ + test_opt(sb, JOURNAL_CHECKSUM)) { + ext4_msg(sb, KERN_ERR, "changing journal_checksum " + "during remount not supported"); + err = -EINVAL; + goto restore_opts; + } + if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) { if (test_opt2(sb, EXPLICIT_DELALLOC)) { ext4_msg(sb, KERN_ERR, "can't mount with " -- 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