Delete snapshot make filesystem read-only

Tags:

Answer: 1

19 hours ago

I am using Btrfs 3.12 and each time i delete a snapshot, the entire btrfs volume become "Read only". So i umount it and try a

btrfsck --repair

But every time it failed on this line:

Extent back ref already exists for 4788162379776 parent 0 root 258
Extent back ref already exists for 4788162789376 parent 0 root 258
Abandon (core dumped)

Here is the result dsmeg (last lines because there are tons)

 scsi 6:0:0:0: Direct-Access     EQLOGIC  100E-00          7.0  PQ: 0 ANSI: 5     
 sd 5:0:0:0: Attached scsi generic sg9 type 0     
 sd 6:0:0:0: Attached scsi generic sg10 type 0     
 sd 5:0:0:0: [sde] 2684355840 4096-byte logical blocks: (10.9 TB/10.0 TiB)     
 sd 6:0:0:0: [sdf] 2684355840 4096-byte logical blocks: (10.9 TB/10.0 TiB)     
 sd 10:0:0:0: [sdd] Write Protect is off     
 sd 10:0:0:0: [sdd] Mode Sense: 81 00 00 00     
 sd 9:0:0:0: [sdc] Write Protect is off     
 sd 9:0:0:0: [sdc] Mode Sense: 81 00 00 00     
 sd 10:0:0:0: [sdd] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA     
 sd 9:0:0:0: [sdc] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA     
 sd 6:0:0:0: [sdf] Write Protect is off     
 sd 6:0:0:0: [sdf] Mode Sense: 81 00 00 00     
 sd 5:0:0:0: [sde] Write Protect is off     
 sd 5:0:0:0: [sde] Mode Sense: 81 00 00 00     
 sd 6:0:0:0: [sdf] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA     
 sd 9:0:0:0: [sdc] 2684355840 4096-byte logical blocks: (10.9 TB/10.0 TiB)     
 sd 5:0:0:0: [sde] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA     
 sd 10:0:0:0: [sdd] 2684355840 4096-byte logical blocks: (10.9 TB/10.0 TiB)     
 sd 5:0:0:0: [sde] 2684355840 4096-byte logical blocks: (10.9 TB/10.0 TiB)     
 sd 6:0:0:0: [sdf] 2684355840 4096-byte logical blocks: (10.9 TB/10.0 TiB)     
 scsi 7:0:0:0: Direct-Access     EQLOGIC  100E-00          7.0  PQ: 0 ANSI: 5     
 sd 7:0:0:0: Attached scsi generic sg11 type 0     
 sd 7:0:0:0: [sdg] 348967680 4096-byte logical blocks: (1.42 TB/1.29 TiB)     
 scsi 8:0:0:0: Direct-Access     EQLOGIC  100E-00          7.0  PQ: 0 ANSI: 5     
 sd 8:0:0:0: Attached scsi generic sg12 type 0     
 sd 7:0:0:0: [sdg] Write Protect is off     
 sd 7:0:0:0: [sdg] Mode Sense: 81 00 00 00     
 sd 7:0:0:0: [sdg] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA     
 sd 8:0:0:0: [sdh] 348967680 4096-byte logical blocks: (1.42 TB/1.29 TiB)     
 sd 7:0:0:0: [sdg] 348967680 4096-byte logical blocks: (1.42 TB/1.29 TiB)     
 sd 8:0:0:0: [sdh] Write Protect is off     
 sd 8:0:0:0: [sdh] Mode Sense: 81 00 00 00     
 sd 8:0:0:0: [sdh] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA     
 sd 8:0:0:0: [sdh] 348967680 4096-byte logical blocks: (1.42 TB/1.29 TiB)     
  sdg: sdg1     
  sdh: sdh1     
 sd 8:0:0:0: [sdh] 348967680 4096-byte logical blocks: (1.42 TB/1.29 TiB)     
 sd 7:0:0:0: [sdg] 348967680 4096-byte logical blocks: (1.42 TB/1.29 TiB)     
 sd 8:0:0:0: [sdh] Attached SCSI disk     
 sd 7:0:0:0: [sdg] Attached SCSI disk     
  sde: unknown partition table     
  sdf: unknown partition table     
 sd 5:0:0:0: [sde] 2684355840 4096-byte logical blocks: (10.9 TB/10.0 TiB)     
 sd 6:0:0:0: [sdf] 2684355840 4096-byte logical blocks: (10.9 TB/10.0 TiB)     
 sd 5:0:0:0: [sde] Attached SCSI disk     
 sd 6:0:0:0: [sdf] Attached SCSI disk     
  sdd: unknown partition table     
  sdc: unknown partition table     
 sd 9:0:0:0: [sdc] 2684355840 4096-byte logical blocks: (10.9 TB/10.0 TiB)     
 sd 10:0:0:0: [sdd] 2684355840 4096-byte logical blocks: (10.9 TB/10.0 TiB)     
 sd 9:0:0:0: [sdc] Attached SCSI disk     
 sd 10:0:0:0: [sdd] Attached SCSI disk     
 device-mapper: multipath round-robin: version 1.0.0 loaded     
 bio: create slab <bio-2> at 2     
 bio: create slab <bio-3> at 3     
 btrfs: device fsid dd26758b-a689-46a8-b4da-b5ecc07d73b6 devid 1 transid 135638 /dev/dm-0     
 btrfs: device fsid dd26758b-a689-46a8-b4da-b5ecc07d73b6 devid 2 transid 135638 /dev/dm-1     
 btrfs: device fsid dd26758b-a689-46a8-b4da-b5ecc07d73b6 devid 2 transid 135638 /dev/dm-1     
 btrfs: device fsid dd26758b-a689-46a8-b4da-b5ecc07d73b6 devid 1 transid 135638 /dev/dm-0     
 btrfs: device fsid dd26758b-a689-46a8-b4da-b5ecc07d73b6 devid 2 transid 135638 /dev/dm-1     
 perf samples too long (2511 > 2500), lowering kernel.perf_event_max_sample_rate to 50000     
 show_signal_msg: 81 callbacks suppressed     
 btrfsck[2604]: segfault at 0 ip 000000000041243a sp 00007fffe6793e40 error 6 in btrfsck[400000+53000]  

I also found a file: /var/crash/_sbin_btrfsck.0.crash Here is the end of lines:

  7f127eb34000-7f127eb36000 rw-p 00000000 00:00 0          
  7f127eb36000-7f127eb37000 r--p 00022000 08:11 5374145                    /lib/x86_64-linux-gnu/ld-2.15.so          
  7f127eb37000-7f127eb39000 rw-p 00023000 08:11 5374145                    /lib/x86_64-linux-gnu/ld-2.15.so          
  7fffd36b4000-7fffd36d5000 rw-p 00000000 00:00 0                          [stack]          
  7fffd378c000-7fffd378e000 r-xp 00000000 00:00 0                          [vdso]          
  ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]          
 ProcStatus:          
  Name:  btrfsck          
  State: S (sleeping)          
  Tgid:  9512          
  Ngid:  0          
  Pid:   9512          
  PPid:  5436          
  TracerPid:     0          
  Uid:   0       0       0       0          
  Gid:   0       0       0       0          
  FDSize:        256          
  Groups:        0          
  VmPeak:         8855944 kB          
  VmSize:         8855944 kB          
  VmLck:        0 kB          
  VmPin:        0 kB          
  VmHWM:  7644076 kB          
  VmRSS:  7432256 kB          
  VmData:         8835640 kB          
  VmStk:      136 kB          
  VmExe:      332 kB          
  VmLib:     3364 kB          
  VmPTE:    17324 kB          
  VmSwap:         1404244 kB          
  Threads:       1          
  SigQ:  1/63594          
  SigPnd:        0000000000000000          
  ShdPnd:        0000000000000000          
  SigBlk:        0000000000000000          
  SigIgn:        0000000000000000          
  SigCgt:        0000000180000000          
  CapInh:        0000000000000000          
  CapPrm:        0000001fffffffff          
  CapEff:        0000001fffffffff          
  CapBnd:        0000001fffffffff          
  Seccomp:       0          
  Cpus_allowed:  ffffffff          
  Cpus_allowed_list:     0-31          
  Mems_allowed:  00000000,00000001          
  Mems_allowed_list:     0          
  voluntary_ctxt_switches:       77639          
  nonvoluntary_ctxt_switches:    377681          
 Signal: 6          
 Uname: Linux 3.13.0-031300-generic x86_64          

Regards,

Added by: Felipe Cremin

Answer: 2

10 hours ago

You have encountered two problems, which do not have to be related to each other.

  • Each time i delete a snapshot, the entire btrfs volume become "Read only".

dmesg does not give any clue about that.

  • btrfsck --repair crashes with signal 6 (as mentioned in the .crash file)

This is a bug.

Added by: Scot Marks

Popular Search

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 1 2 3 4 5 6 7 8 9