I had a cronjob that mistakenly created and deleted snapshots in the same place at the same time. Interesting output I got: /var/local/scr/btrfs_snaps: line 23: 26017 Segmentation fault (core dumped) /sbin/btrfs subvolume delete "$sub" On ubuntu precise (i.e. super ancient), but I upgraded userland: polgara:~$ btrfs --version Btrfs v0.20-rc1 Kernel 3.2.5. Sorry, aptport stole my crashes and apparently didn''t give a backtrace, but that''s what I have if this helps: ProblemType: Crash Architecture: amd64 Date: Thu Sep 26 22:00:03 2013 DistroRelease: Ubuntu 12.04 ExecutablePath: /sbin/btrfs ExecutableTimestamp: 1380251279 ProcCmdline: /sbin/btrfs subvolume delete google_hourly_20130926_19:00:01 ProcCwd: /mnt/btrfs_pool1 ProcEnviron: SHELL=/bin/sh PATH=(custom, no user) ProcMaps: 00400000-00442000 r-xp 00000000 fc:00 399893 /sbin/btrfs 00641000-00643000 r--p 00041000 fc:00 399893 /sbin/btrfs 00643000-00644000 rw-p 00043000 fc:00 399893 /sbin/btrfs 00644000-00646000 rw-p 00000000 00:00 0 01b05000-01b26000 rw-p 00000000 00:00 0 [heap] 7fb153b8e000-7fb153d43000 r-xp 00000000 fc:00 2232563 /lib/x86_64-linux-gnu/libc-2.15.so 7fb153d43000-7fb153f42000 ---p 001b5000 fc:00 2232563 /lib/x86_64-linux-gnu/libc-2.15.so 7fb153f42000-7fb153f46000 r--p 001b4000 fc:00 2232563 /lib/x86_64-linux-gnu/libc-2.15.so 7fb153f46000-7fb153f48000 rw-p 001b8000 fc:00 2232563 /lib/x86_64-linux-gnu/libc-2.15.so 7fb153f48000-7fb153f4d000 rw-p 00000000 00:00 0 7fb153f4d000-7fb153f65000 r-xp 00000000 fc:00 2233530 /lib/x86_64-linux-gnu/libpthread-2.15.so 7fb153f65000-7fb154164000 ---p 00018000 fc:00 2233530 /lib/x86_64-linux-gnu/libpthread-2.15.so 7fb154164000-7fb154165000 r--p 00017000 fc:00 2233530 /lib/x86_64-linux-gnu/libpthread-2.15.so 7fb154165000-7fb154166000 rw-p 00018000 fc:00 2233530 /lib/x86_64-linux-gnu/libpthread-2.15.so 7fb154166000-7fb15416a000 rw-p 00000000 00:00 0 7fb15416a000-7fb15416d000 r-xp 00000000 fc:00 2228482 /lib/x86_64-linux-gnu/libcom_err.so.2.1 7fb15416d000-7fb15436c000 ---p 00003000 fc:00 2228482 /lib/x86_64-linux-gnu/libcom_err.so.2.1 7fb15436c000-7fb15436d000 r--p 00002000 fc:00 2228482 /lib/x86_64-linux-gnu/libcom_err.so.2.1 7fb15436d000-7fb15436e000 rw-p 00003000 fc:00 2228482 /lib/x86_64-linux-gnu/libcom_err.so.2.1 7fb15436e000-7fb15438e000 r-xp 00000000 fc:00 2232137 /lib/liblzo2.so.2 7fb15438e000-7fb15458d000 ---p 00020000 fc:00 2232137 /lib/liblzo2.so.2 7fb15458d000-7fb15458e000 rw-p 0001f000 fc:00 2232137 /lib/liblzo2.so.2 7fb15458e000-7fb1545a4000 r-xp 00000000 fc:00 2228617 /lib/x86_64-linux-gnu/libz.so.1.2.3.4 7fb1545a4000-7fb1547a3000 ---p 00016000 fc:00 2228617 /lib/x86_64-linux-gnu/libz.so.1.2.3.4 7fb1547a3000-7fb1547a4000 r--p 00015000 fc:00 2228617 /lib/x86_64-linux-gnu/libz.so.1.2.3.4 7fb1547a4000-7fb1547a5000 rw-p 00016000 fc:00 2228617 /lib/x86_64-linux-gnu/libz.so.1.2.3.4 7fb1547a5000-7fb1548a0000 r-xp 00000000 fc:00 2256906 /lib/x86_64-linux-gnu/libm-2.15.so 7fb1548a0000-7fb154a9f000 ---p 000fb000 fc:00 2256906 /lib/x86_64-linux-gnu/libm-2.15.so 7fb154a9f000-7fb154aa0000 r--p 000fa000 fc:00 2256906 /lib/x86_64-linux-gnu/libm-2.15.so 7fb154aa0000-7fb154aa1000 rw-p 000fb000 fc:00 2256906 /lib/x86_64-linux-gnu/libm-2.15.so 7fb154aa1000-7fb154ac3000 r-xp 00000000 fc:00 2228442 /lib/x86_64-linux-gnu/libblkid.so.1.1.0 7fb154ac3000-7fb154cc3000 ---p 00022000 fc:00 2228442 /lib/x86_64-linux-gnu/libblkid.so.1.1.0 7fb154cc3000-7fb154cc6000 r--p 00022000 fc:00 2228442 /lib/x86_64-linux-gnu/libblkid.so.1.1.0 7fb154cc6000-7fb154cc7000 rw-p 00025000 fc:00 2228442 /lib/x86_64-linux-gnu/libblkid.so.1.1.0 7fb154cc7000-7fb154ccb000 r-xp 00000000 fc:00 2228602 /lib/x86_64-linux-gnu/libuuid.so.1.3.0 7fb154ccb000-7fb154eca000 ---p 00004000 fc:00 2228602 /lib/x86_64-linux-gnu/libuuid.so.1.3.0 7fb154eca000-7fb154ecb000 r--p 00003000 fc:00 2228602 /lib/x86_64-linux-gnu/libuuid.so.1.3.0 7fb154ecb000-7fb154ecc000 rw-p 00004000 fc:00 2228602 /lib/x86_64-linux-gnu/libuuid.so.1.3.0 7fb154ecc000-7fb154eee000 r-xp 00000000 fc:00 2256912 /lib/x86_64-linux-gnu/ld-2.15.so 7fb1550c6000-7fb1550cb000 rw-p 00000000 00:00 0 7fb1550ec000-7fb1550ee000 rw-p 00000000 00:00 0 7fb1550ee000-7fb1550ef000 r--p 00022000 fc:00 2256912 /lib/x86_64-linux-gnu/ld-2.15.so 7fb1550ef000-7fb1550f1000 rw-p 00023000 fc:00 2256912 /lib/x86_64-linux-gnu/ld-2.15.so 7fffe703f000-7fffe7060000 rw-p 00000000 00:00 0 [stack] 7fffe70df000-7fffe70e0000 r-xp 00000000 00:00 0 [vdso] ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall] ProcStatus: Name: btrfs State: S (sleeping) Tgid: 31926 Pid: 31926 PPid: 31856 TracerPid: 0 Uid: 0 0 0 0 Gid: 0 0 0 0 FDSize: 256 Groups: 0 128 71252 VmPeak: 20440 kB VmSize: 20436 kB VmLck: 0 kB VmPin: 0 kB VmHWM: 824 kB VmRSS: 824 kB VmData: 208 kB VmStk: 136 kB VmExe: 264 kB VmLib: 3364 kB VmPTE: 64 kB VmSwap: 0 kB Threads: 1 SigQ: 8/514713 SigPnd: 0000000000000000 ShdPnd: 0000000000000000 SigBlk: 0000000000000000 SigIgn: 0000000000000000 SigCgt: 0000000180000000 CapInh: 0000000000000000 CapPrm: ffffffffffffffff CapEff: ffffffffffffffff CapBnd: ffffffffffffffff Cpus_allowed: ffffffff Cpus_allowed_list: 0-31 Mems_allowed: 00000000,00000003 Mems_allowed_list: 0-1 voluntary_ctxt_switches: 3 nonvoluntary_ctxt_switches: 1 Signal: 11 Uname: Linux 3.2.5-gg1336 x86_64 UserGroups: pkcs11 root root -- "A mouse is a device used to point at the xterm you want to type in" - A.S.R. Microsoft is to operating systems .... .... what McDonalds is to gourmet cooking Home page: http://marc.merlins.org/ -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html