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[Bug 1526692] Re: Ubuntu 15.10 - btrfs - Kernel Panic on btrfs balance

To: kernel-packages@xxxxxxxxxxxxxxxxxxx
From: David Miller <1526692@xxxxxxxxxxxxxxxxxx>
Date: Thu, 24 Dec 2015 02:27:56 -0000
Reply-to: Bug 1526692 <1526692@xxxxxxxxxxxxxxxxxx>
Sender: bounces@xxxxxxxxxxxxx
I've run into a similar issue running balance on a 3 disk btrfs
filesystem with data and metadata set to raid 1.   I can't confirm that
I'm seeing this same exact error as I don't have any of the log output
as my entire system is running on this btrfs volume.  Only was able to
see the output over the IPMI KVM Console.

Upgrading to kernel 4.3.3 seems to address my  issue.   I'll reboot back
onto the default 15.10 kernel and try to reproduce again to see if I can
verify that the issue I was seeing is the same.

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https://bugs.launchpad.net/bugs/1526692

Title:
  Ubuntu 15.10 - btrfs - Kernel Panic on btrfs balance

Status in linux package in Ubuntu:
  Incomplete

Bug description:

  
  [  360.220144] INFO: task btrfs:2938 blocked for more than 120 seconds.
  [  360.220152]       Tainted: G           OE   4.2.0-19-generic #23-Ubuntu
  [  360.220153] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [  360.220155] btrfs           D ffff88087fc16640     0  2938   2937 0x00000000
  [  360.220161]  ffff880833b87c78 0000000000000086 ffffffff81c13500 ffff880835525940
  [  360.220163]  0000000000000246 ffff880833b88000 ffff88085b9c0c70 ffff88085b9c0cb0
  [  360.220165]  ffff880855758980 ffff8807f2c97300 ffff880833b87c98 ffffffff817ec197
  [  360.220167] Call Trace:
  [  360.220179]  [<ffffffff817ec197>] schedule+0x37/0x80
  [  360.220221]  [<ffffffffc03fc197>] btrfs_cancel_balance+0x127/0x180 [btrfs]
  [  360.220225]  [<ffffffff810bd110>] ? wake_atomic_t_function+0x60/0x60
  [  360.220238]  [<ffffffffc040bd25>] btrfs_ioctl+0xd55/0x2760 [btrfs]
  [  360.220243]  [<ffffffff81192b7b>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
  [  360.220247]  [<ffffffff811b5127>] ? handle_mm_fault+0xc77/0x17e0
  [  360.220249]  [<ffffffff811b8acd>] ? __vma_link_rb+0xfd/0x110
  [  360.220251]  [<ffffffff811b8b99>] ? vma_link+0xb9/0xc0
  [  360.220254]  [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480
  [  360.220256]  [<ffffffff81210c89>] SyS_ioctl+0x79/0x90
  [  360.220259]  [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75
  [  360.220264] INFO: task btrfs:3002 blocked for more than 120 seconds.
  [  360.220266]       Tainted: G           OE   4.2.0-19-generic #23-Ubuntu
  [  360.220266] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [  360.220267] btrfs           D ffff88087fd56640     0  3002   3001 0x00000000
  [  360.220270]  ffff8807e340bc78 0000000000000086 ffff88085bf1cc80 ffff880857fa9980
  [  360.220272]  0000000000000246 ffff8807e340c000 ffff88085b9c0c70 ffff88085b9c0cb0
  [  360.220274]  ffff880855758980 ffff88085a181700 ffff8807e340bc98 ffffffff817ec197
  [  360.220276] Call Trace:
  [  360.220278]  [<ffffffff817ec197>] schedule+0x37/0x80
  [  360.220289]  [<ffffffffc03fbfe2>] btrfs_pause_balance+0x92/0x120 [btrfs]
  [  360.220291]  [<ffffffff810bd110>] ? wake_atomic_t_function+0x60/0x60
  [  360.220303]  [<ffffffffc040ca0e>] btrfs_ioctl+0x1a3e/0x2760 [btrfs]
  [  360.220306]  [<ffffffff81192b7b>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
  [  360.220308]  [<ffffffff811b5127>] ? handle_mm_fault+0xc77/0x17e0
  [  360.220310]  [<ffffffff811b8acd>] ? __vma_link_rb+0xfd/0x110
  [  360.220311]  [<ffffffff811b8b99>] ? vma_link+0xb9/0xc0
  [  360.220313]  [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480
  [  360.220315]  [<ffffffff81210c89>] SyS_ioctl+0x79/0x90
  [  360.220317]  [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75
  [  480.220139] INFO: task btrfs:2938 blocked for more than 120 seconds.
  [  480.220148]       Tainted: G           OE   4.2.0-19-generic #23-Ubuntu
  [  480.220149] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [  480.220152] btrfs           D ffff88087fc16640     0  2938   2937 0x00000000
  [  480.220159]  ffff880833b87c78 0000000000000086 ffffffff81c13500 ffff880835525940
  [  480.220162]  0000000000000246 ffff880833b88000 ffff88085b9c0c70 ffff88085b9c0cb0
  [  480.220166]  ffff880855758980 ffff8807f2c97300 ffff880833b87c98 ffffffff817ec197
  [  480.220169] Call Trace:
  [  480.220180]  [<ffffffff817ec197>] schedule+0x37/0x80
  [  480.220217]  [<ffffffffc03fc197>] btrfs_cancel_balance+0x127/0x180 [btrfs]
  [  480.220222]  [<ffffffff810bd110>] ? wake_atomic_t_function+0x60/0x60
  [  480.220234]  [<ffffffffc040bd25>] btrfs_ioctl+0xd55/0x2760 [btrfs]
  [  480.220238]  [<ffffffff81192b7b>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
  [  480.220241]  [<ffffffff811b5127>] ? handle_mm_fault+0xc77/0x17e0
  [  480.220243]  [<ffffffff811b8acd>] ? __vma_link_rb+0xfd/0x110
  [  480.220245]  [<ffffffff811b8b99>] ? vma_link+0xb9/0xc0
  [  480.220248]  [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480
  [  480.220250]  [<ffffffff81210c89>] SyS_ioctl+0x79/0x90
  [  480.220253]  [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75
  [  480.220257] INFO: task btrfs:3002 blocked for more than 120 seconds.
  [  480.220258]       Tainted: G           OE   4.2.0-19-generic #23-Ubuntu
  [  480.220259] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [  480.220260] btrfs           D ffff88087fd56640     0  3002   3001 0x00000000
  [  480.220263]  ffff8807e340bc78 0000000000000086 ffff88085bf1cc80 ffff880857fa9980
  [  480.220265]  0000000000000246 ffff8807e340c000 ffff88085b9c0c70 ffff88085b9c0cb0
  [  480.220266]  ffff880855758980 ffff88085a181700 ffff8807e340bc98 ffffffff817ec197
  [  480.220268] Call Trace:
  [  480.220270]  [<ffffffff817ec197>] schedule+0x37/0x80
  [  480.220282]  [<ffffffffc03fbfe2>] btrfs_pause_balance+0x92/0x120 [btrfs]
  [  480.220283]  [<ffffffff810bd110>] ? wake_atomic_t_function+0x60/0x60
  [  480.220294]  [<ffffffffc040ca0e>] btrfs_ioctl+0x1a3e/0x2760 [btrfs]
  [  480.220297]  [<ffffffff81192b7b>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
  [  480.220299]  [<ffffffff811b5127>] ? handle_mm_fault+0xc77/0x17e0
  [  480.220301]  [<ffffffff811b8acd>] ? __vma_link_rb+0xfd/0x110
  [  480.220302]  [<ffffffff811b8b99>] ? vma_link+0xb9/0xc0
  [  480.220304]  [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480
  [  480.220306]  [<ffffffff81210c89>] SyS_ioctl+0x79/0x90
  [  480.220308]  [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75
  [  568.995645] audit: type=1400 audit(1450161017.458:22): apparmor="STATUS" operation="profile_load" profile="unconfined" name="libvirt-313c039d-5b69-4fa1-ac3c-c2599868e26b" pid=3495 comm="apparmor_parser"
  [  568.995912] audit: type=1400 audit(1450161017.458:23): apparmor="STATUS" operation="profile_load" profile="unconfined" name="qemu_bridge_helper" pid=3495 comm="apparmor_parser"
  [  569.072231] device vnet2 entered promiscuous mode
  [  569.096185] br0: port 4(vnet2) entered listening state
  [  569.096209] br0: port 4(vnet2) entered listening state
  [  569.400115] audit: type=1400 audit(1450161017.866:24): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="libvirt-313c039d-5b69-4fa1-ac3c-c2599868e26b" pid=3520 comm="apparmor_parser"
  [  569.412287] audit: type=1400 audit(1450161017.878:25): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="qemu_bridge_helper" pid=3520 comm="apparmor_parser"
  [  572.783905] kvm: zapping shadow pages for mmio generation wraparound
  [  584.124014] br0: port 4(vnet2) entered learning state
  [  596.400977] kvm [3522]: vcpu0 unhandled rdmsr: 0x570
  [  599.132011] br0: topology change detected, propagating
  [  599.132024] br0: port 4(vnet2) entered forwarding state
  [  600.220107] INFO: task btrfs:2938 blocked for more than 120 seconds.
  [  600.220121]       Tainted: G           OE   4.2.0-19-generic #23-Ubuntu
  [  600.220126] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [  600.220129] btrfs           D ffff88087fc16640     0  2938   2937 0x00000000
  [  600.220139]  ffff880833b87c78 0000000000000086 ffffffff81c13500 ffff880835525940
  [  600.220141]  0000000000000246 ffff880833b88000 ffff88085b9c0c70 ffff88085b9c0cb0
  [  600.220143]  ffff880855758980 ffff8807f2c97300 ffff880833b87c98 ffffffff817ec197
  [  600.220146] Call Trace:
  [  600.220155]  [<ffffffff817ec197>] schedule+0x37/0x80
  [  600.220196]  [<ffffffffc03fc197>] btrfs_cancel_balance+0x127/0x180 [btrfs]
  [  600.220199]  [<ffffffff810bd110>] ? wake_atomic_t_function+0x60/0x60
  [  600.220211]  [<ffffffffc040bd25>] btrfs_ioctl+0xd55/0x2760 [btrfs]
  [  600.220216]  [<ffffffff81192b7b>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
  [  600.220219]  [<ffffffff811b5127>] ? handle_mm_fault+0xc77/0x17e0
  [  600.220221]  [<ffffffff811b8acd>] ? __vma_link_rb+0xfd/0x110
  [  600.220223]  [<ffffffff811b8b99>] ? vma_link+0xb9/0xc0
  [  600.220226]  [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480
  [  600.220228]  [<ffffffff81210c89>] SyS_ioctl+0x79/0x90
  [  600.220231]  [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75
  [  600.220234] INFO: task btrfs:3002 blocked for more than 120 seconds.
  [  600.220236]       Tainted: G           OE   4.2.0-19-generic #23-Ubuntu
  [  600.220237] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [  600.220237] btrfs           D ffff88087fd56640     0  3002   3001 0x00000004
  [  600.220240]  ffff8807e340bc78 0000000000000086 ffff88085bf1cc80 ffff880857fa9980
  [  600.220242]  0000000000000246 ffff8807e340c000 ffff88085b9c0c70 ffff88085b9c0cb0
  [  600.220244]  ffff880855758980 ffff88085a181700 ffff8807e340bc98 ffffffff817ec197
  [  600.220246] Call Trace:
  [  600.220248]  [<ffffffff817ec197>] schedule+0x37/0x80
  [  600.220259]  [<ffffffffc03fbfe2>] btrfs_pause_balance+0x92/0x120 [btrfs]
  [  600.220261]  [<ffffffff810bd110>] ? wake_atomic_t_function+0x60/0x60
  [  600.220272]  [<ffffffffc040ca0e>] btrfs_ioctl+0x1a3e/0x2760 [btrfs]
  [  600.220274]  [<ffffffff81192b7b>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
  [  600.220276]  [<ffffffff811b5127>] ? handle_mm_fault+0xc77/0x17e0
  [  600.220278]  [<ffffffff811b8acd>] ? __vma_link_rb+0xfd/0x110
  [  600.220280]  [<ffffffff811b8b99>] ? vma_link+0xb9/0xc0
  [  600.220282]  [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480
  [  600.220283]  [<ffffffff81210c89>] SyS_ioctl+0x79/0x90
  [  600.220286]  [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75
  [  720.220100] INFO: task btrfs:2938 blocked for more than 120 seconds.
  [  720.220108]       Tainted: G           OE   4.2.0-19-generic #23-Ubuntu
  [  720.220110] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [  720.220113] btrfs           D ffff88087fc16640     0  2938   2937 0x00000000
  [  720.220119]  ffff880833b87c78 0000000000000086 ffffffff81c13500 ffff880835525940
  [  720.220123]  0000000000000246 ffff880833b88000 ffff88085b9c0c70 ffff88085b9c0cb0
  [  720.220126]  ffff880855758980 ffff8807f2c97300 ffff880833b87c98 ffffffff817ec197
  [  720.220129] Call Trace:
  [  720.220140]  [<ffffffff817ec197>] schedule+0x37/0x80
  [  720.220182]  [<ffffffffc03fc197>] btrfs_cancel_balance+0x127/0x180 [btrfs]
  [  720.220186]  [<ffffffff810bd110>] ? wake_atomic_t_function+0x60/0x60
  [  720.220198]  [<ffffffffc040bd25>] btrfs_ioctl+0xd55/0x2760 [btrfs]
  [  720.220203]  [<ffffffff81192b7b>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
  [  720.220206]  [<ffffffff811b5127>] ? handle_mm_fault+0xc77/0x17e0
  [  720.220208]  [<ffffffff811b8acd>] ? __vma_link_rb+0xfd/0x110
  [  720.220210]  [<ffffffff811b8b99>] ? vma_link+0xb9/0xc0
  [  720.220213]  [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480
  [  720.220215]  [<ffffffff81210c89>] SyS_ioctl+0x79/0x90
  [  720.220218]  [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75
  [  720.220221] INFO: task btrfs:3002 blocked for more than 120 seconds.
  [  720.220223]       Tainted: G           OE   4.2.0-19-generic #23-Ubuntu
  [  720.220223] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [  720.220224] btrfs           D ffff88087fd56640     0  3002   3001 0x00000004
  [  720.220227]  ffff8807e340bc78 0000000000000086 ffff88085bf1cc80 ffff880857fa9980
  [  720.220229]  0000000000000246 ffff8807e340c000 ffff88085b9c0c70 ffff88085b9c0cb0
  [  720.220231]  ffff880855758980 ffff88085a181700 ffff8807e340bc98 ffffffff817ec197
  [  720.220233] Call Trace:
  [  720.220234]  [<ffffffff817ec197>] schedule+0x37/0x80
  [  720.220246]  [<ffffffffc03fbfe2>] btrfs_pause_balance+0x92/0x120 [btrfs]
  [  720.220247]  [<ffffffff810bd110>] ? wake_atomic_t_function+0x60/0x60
  [  720.220259]  [<ffffffffc040ca0e>] btrfs_ioctl+0x1a3e/0x2760 [btrfs]
  [  720.220261]  [<ffffffff81192b7b>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
  [  720.220263]  [<ffffffff811b5127>] ? handle_mm_fault+0xc77/0x17e0
  [  720.220265]  [<ffffffff811b8acd>] ? __vma_link_rb+0xfd/0x110
  [  720.220266]  [<ffffffff811b8b99>] ? vma_link+0xb9/0xc0
  [  720.220268]  [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480
  [  720.220270]  [<ffffffff81210c89>] SyS_ioctl+0x79/0x90
  [  720.220272]  [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75
  [  840.220097] INFO: task btrfs:2938 blocked for more than 120 seconds.
  [  840.220104]       Tainted: G           OE   4.2.0-19-generic #23-Ubuntu
  [  840.220105] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [  840.220107] btrfs           D ffff88087fc16640     0  2938   2937 0x00000000
  [  840.220112]  ffff880833b87c78 0000000000000086 ffffffff81c13500 ffff880835525940
  [  840.220114]  0000000000000246 ffff880833b88000 ffff88085b9c0c70 ffff88085b9c0cb0
  [  840.220116]  ffff880855758980 ffff8807f2c97300 ffff880833b87c98 ffffffff817ec197
  [  840.220118] Call Trace:
  [  840.220128]  [<ffffffff817ec197>] schedule+0x37/0x80
  [  840.220159]  [<ffffffffc03fc197>] btrfs_cancel_balance+0x127/0x180 [btrfs]
  [  840.220163]  [<ffffffff810bd110>] ? wake_atomic_t_function+0x60/0x60
  [  840.220175]  [<ffffffffc040bd25>] btrfs_ioctl+0xd55/0x2760 [btrfs]
  [  840.220180]  [<ffffffff81192b7b>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
  [  840.220183]  [<ffffffff811b5127>] ? handle_mm_fault+0xc77/0x17e0
  [  840.220185]  [<ffffffff811b8acd>] ? __vma_link_rb+0xfd/0x110
  [  840.220187]  [<ffffffff811b8b99>] ? vma_link+0xb9/0xc0
  [  840.220190]  [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480
  [  840.220192]  [<ffffffff81210c89>] SyS_ioctl+0x79/0x90
  [  840.220195]  [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75
  [  840.220198] INFO: task btrfs:3002 blocked for more than 120 seconds.
  [  840.220200]       Tainted: G           OE   4.2.0-19-generic #23-Ubuntu
  [  840.220201] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [  840.220202] btrfs           D ffff88087fd56640     0  3002   3001 0x00000004
  [  840.220204]  ffff8807e340bc78 0000000000000086 ffff88085bf1cc80 ffff880857fa9980
  [  840.220206]  0000000000000246 ffff8807e340c000 ffff88085b9c0c70 ffff88085b9c0cb0
  [  840.220208]  ffff880855758980 ffff88085a181700 ffff8807e340bc98 ffffffff817ec197
  [  840.220210] Call Trace:
  [  840.220212]  [<ffffffff817ec197>] schedule+0x37/0x80
  [  840.220223]  [<ffffffffc03fbfe2>] btrfs_pause_balance+0x92/0x120 [btrfs]
  [  840.220225]  [<ffffffff810bd110>] ? wake_atomic_t_function+0x60/0x60
  [  840.220236]  [<ffffffffc040ca0e>] btrfs_ioctl+0x1a3e/0x2760 [btrfs]
  [  840.220239]  [<ffffffff81192b7b>] ? lru_cache_add_active_or_unevictable+0x2b/0xa0
  [  840.220241]  [<ffffffff811b5127>] ? handle_mm_fault+0xc77/0x17e0
  [  840.220242]  [<ffffffff811b8acd>] ? __vma_link_rb+0xfd/0x110
  [  840.220244]  [<ffffffff811b8b99>] ? vma_link+0xb9/0xc0
  [  840.220246]  [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480
  [  840.220248]  [<ffffffff81210c89>] SyS_ioctl+0x79/0x90
  [  840.220250]  [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75
  --- 
  ApportVersion: 2.19.1-0ubuntu5
  Architecture: amd64
  AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
  DistroRelease: Ubuntu 15.10
  HibernationDevice: RESUME=UUID=980993fc-6c0b-4081-b7db-803bf1c95cb9
  InstallationDate: Installed on 2015-09-10 (96 days ago)
  InstallationMedia: Ubuntu-Server 15.04 "Vivid Vervet" - Release amd64 (20150422)
  MachineType: Dell Inc. PowerEdge 2950
  Package: linux-image-generic 4.2.0.19.21
  PackageArchitecture: amd64
  ProcEnviron:
   TERM=xterm
   PATH=(custom, no user)
   LANG=de_DE.UTF-8
   SHELL=/bin/bash
  ProcFB: 0 radeondrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.2.0-19-generic root=UUID=5fc5358f-103a-409e-9d07-2489c35ddf66 ro rootflags=subvol=@
  ProcVersionSignature: Ubuntu 4.2.0-19.23-generic 4.2.6
  PulseList:
   Error: command ['pacmd', 'list'] failed with exit code 1: Home directory not accessible: Permission denied
   No PulseAudio daemon running, or not running as session daemon.
  RelatedPackageVersions:
   linux-restricted-modules-4.2.0-19-generic N/A
   linux-backports-modules-4.2.0-19-generic  N/A
   linux-firmware                            1.149.3
  RfKill:
   
  Tags:  wily
  UdevLog: Error: [Errno 2] Datei oder Verzeichnis nicht gefunden: '/var/log/udev'
  Uname: Linux 4.2.0-19-generic x86_64
  UpgradeStatus: Upgraded to wily on 2015-11-04 (41 days ago)
  UserGroups:
   
  _MarkForUpload: True
  dmi.bios.date: 10/30/2010
  dmi.bios.vendor: Dell Inc.
  dmi.bios.version: 2.7.0
  dmi.board.name: 0H603H
  dmi.board.vendor: Dell Inc.
  dmi.board.version: A06
  dmi.chassis.type: 23
  dmi.chassis.vendor: Dell Inc.
  dmi.modalias: dmi:bvnDellInc.:bvr2.7.0:bd10/30/2010:svnDellInc.:pnPowerEdge2950:pvr:rvnDellInc.:rn0H603H:rvrA06:cvnDellInc.:ct23:cvr:
  dmi.product.name: PowerEdge 2950
  dmi.sys.vendor: Dell Inc.

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References

[Bug 1526692] [NEW] Ubuntu 15.10 - btrfs - Kernel Panic on btrfs balance
From: S. W., 2015-12-16