Andrei Volt
2014-May-25 18:26 UTC
mount fails with "double free or corruption" after failed
resize operation Reply-To: Hello all, Someone on #archlinux suggested I post this problem I'm having on this mailing list. Apologies if this is off-topic, although I believe it's not. After a failed resize operation (shrink of 30 GB, waited 8 hours, iotop reporting 50 M/s writes, no reads), my btrfs partition wouldn't mount, complaining about "double free or corruption". I finally managed to mount the filesystem after a btrfs-zero-log and reboot. I've run an additional backup, a bit more up to date then my previous one, but obviously the error message worries me a bit. How can I make sure the data is intact? What kind of corruption could occur? (what's the worse that could happen? so far I'm not seeing anything unusual). I didn't do anything else apart from the resize operation, a few btrfsck(s) which failed immediately, and the btrfs-zero-log operation. I should mention that on the second to last reboot the mount failed again, and it only mounted again correctly after zero-log + reboot. (same error, "double free or corruption", after a bunch of output that got cleared from the scrollback buffer. I've made a backup via rsync but when I try to du -sc the backup and the original, the original reports "infinity" (although this is not new), and the backup errors out on some files (which is why I'd rather not go from the restore from backup option, until I'm sure the backup is correct) What should I do to: 1. (ideally) repair the FS. Right now it _seems_ to be failing on every other boot, and I have to run btrfs-zero-log to mount, and even then it only mounts successfully on reboot. 2. check for data integrity 3. check that my backup is correct? Here's the output of the commands suggested on the wiki: Linux 3.13.9-1-ck #1 SMP PREEMPT Fri Apr 18 23:21:44 CEST 2014 x86_64 GNU/Linux Btrfs v3.14.1 Data, single: total=188.99GiB, used=143.17GiB Label: 'root' uuid: 0c2bfb0a-a549-4170-92a5-c4f218c023eb Total devices 1 FS bytes used 25.20GiB devid 1 size 37.97GiB used 37.97GiB path /dev/sda3 Label: 'home' uuid: ea64435d-b24f-453b-8f0a-af7e18726c86 Total devices 1 FS bytes used 145.96GiB devid 1 size 200.00GiB used 193.00GiB path /dev/sda2 System, single: total=4.00MiB, used=28.00KiB Metadata, single: total=4.01GiB, used=2.79GiB I've also ran a btrfs scrub which reported 4 uncorrectable errors. Cheers, Andrei -- Andrei Volt