From: Heinz Mauelshagen <heinzm@xxxxxxxxxx> Because we don't support any feature flags in the dm-raid ondisk metadata yet (see struct dm_raid_superblock, 'features' member), this patch adds a check to ensure no flags are actually set or reject the activation of the RAID mapping. This is to prevent possible data corruption in case of a kernel downgrade when there'll potentially be feature flags set by a future dm-raid target. Signed-off-by: Heinz Mauelshagen <heinzm@xxxxxxxxxx> --- drivers/md/dm-raid.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index a090121..5f05ba0 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -1037,6 +1037,10 @@ static int super_validate(struct raid_set *rs, struct md_rdev *rdev) if (!mddev->events && super_init_validation(mddev, rdev)) return -EINVAL; + rs->ti->error = "Unable to assemble array: No feature flags supported yet"; + if (le32_to_cpu(sb->features)) /* No features supported yet */ + return -EINVAL; + /* Enable bitmap creation for RAID levels != 0 */ mddev->bitmap_info.offset = (rs->raid_type->level) ? to_sector(4096) : 0; rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset; -- 2.5.5 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel