Zach Fuller posted on Thu, 24 Dec 2015 13:15:22 -0600 as excerpted: > I am currently running btrfs on a 2TB GPT drive. The drive is working > fine, still mounts correctly, and I have experienced no data corruption. > Whenever I run "btrfs check" on the drive, it returns 100,000+ messages > stating "bad extent [###, ###), type mismatch with chunk". Whenever I > try to run "btrfs check --repair" it says that it has fixed the errors, > but whenever I run "btrfs check" again, the errors return. Should I be > worried about data/filesystem corruption, > or are these errors meaningless?
> I have my data backed up on 2 different drives, so I can afford to lose > the entire btrfs drive temporarily. > > Here is some info about my system: > > $ uname -[r] > 4.2.5-1-ARCH > > > $ btrfs --version > btrfs-progs v4.3.1 While Chris's reply mentioning a patch is correct, that's not the whole story and I suspect you have a problem, as the patch is in the userspace 4.3.1 you're running. How long have you had the filesystem? Was it likely created with the mkfs.btrfs from btrfs-progs v4.1.1 (July, 2015) as I suspect? If so, you have a problem, as that mkfs.btrfs was buggy and created invalid filesystems. As you have two separate backups and you're not experiencing corruption or the like so far, you should be fine, but if the filesystem was created with that buggy mkfs.btrfs, you need to wipe and recreate it as soon as possible, because it's unstable in its current state and could fail, with massive corruption, at any point. Unfortunately, the bug created filesystems so broken that (last I knew anyway, and your experience agrees) there's no way btrfs check --repair can fix them. The only way to fix it is to blow away the filesystem and recreate it with a mkfs.btrfs that doesn't have the bug that 4.1.1 did. Your 4.3.1 should be fine. (The patch Chris mentioned was to btrfs check, as the first set of patches to it to allow it to detect the problem triggered all sorts of false-positives and pretty much everybody was flagged as having the problem. I believe that was patched in the 4.2 series, however, and you're running 4.3.1, so you should have that patch and the reports shouldn't be false positives. Tho if you didn't create the filesystem with the buggy mkfs.btrfs from v4.1.1, there's likely some other problem to root out, but I'm guessing you did, and thus have the bad filesystem the patched btrfs check is designed to report, and that report is indeed valid.) -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
