Re: bcache kernel panic

[Stefan Boehringer <me@s-boehringer.org>]

Dear Mathias,

thank you for the update. I look forward to the update. For me, it is a 
hard crash as the screen goes green and I cannot input anything anymore. 
I still hear hard-drive activity, so the system seems to be still up 
(maybe usable via ssh, but haven't tried). I have to perform a hard reset.

I have not experienced any data loss.

Thank you, best,

     Stefan

On 2/16/23 19:00, Matthias Ferdinand wrote:
> Hi,
>
> there has been a thread referencing "field-spanning writes" recently:
>
>      https://www.spinics.net/lists/linux-bcache/msg11631.html
>
> I understood this to be some kind of false positive, to be fixed in some
> later relase of 6.1.x kernels.
>
> Does the system become unusable or is this green-screen just a warning?
>
> Regards
> Matthias Ferdinand
>
>
> On Thu, Feb 16, 2023 at 05:58:15PM +0100, Stefan Boehringer wrote:
>> Dear bache maintainer,
>>
>> I would like to report a kernel panic for bcache that is unfortunately not
>> reproducible. I get this error roughly once a week, resulting in a green
>> screen on my system. Please let me know, if I can provide further
>> information to fix the bug. Below dmesg output copy-pasted as instructed.
>>
>> Thank you, best,
>>
>>      Stefan
>>
>>
>> Feb 15 08:44:49.840548 myhost kernel: ------------[ cut here ]------------
>>
>> Feb 15 08:44:49.840614 myhost kernel: memcpy: detected field-spanning write
>> (size 264) of single field "&i
>> ->j" at drivers/md/bcache/journal.c:152 (size 240)
>> Feb 15 08:44:49.840633 myhost kernel: WARNING: CPU: 7 PID: 755 at
>> drivers/md/bcache/journal.c:152 journal_
>> read_bucket+0x3df/0x490 [bcache]
>> Feb 15 08:44:49.840649 myhost kernel: Modules linked in: snd_hwdep(+) kvm(+)
>> snd_pcm videobuf2_vmalloc(+)
>> videobuf2_memops snd_timer videobuf2_v4l2 sr_mod(+) snd real
>> tek cdrom pcspkr efi_pstore k10temp videobuf2_common i2c_piix4
>> hid_plantronics(+) irqbypass pcc_cpufreq(-) mdio_devres joydev soundcore
>> cfg80211 libphy bcache tiny_power_button acpi_cpufreq button fuse configfs
>> dmi_sysfs ip_tables x_tables btusb btrtl btbcm btintel btmtk bluetooth
>> hid_generic uas ecdh_generic usbhid usb_storage rfkill amdgpu
>> crct10dif_pclmul crc32_pclmul polyval_clmulni polyval_generic gf128mul
>> drm_ttm_helper ttm ghash_clmulni_intel iommu_v2 xhci_pci gpu_sched
>> sha512_ssse3 xhci_pci_renesas xhci_hcd drm_buddy aesni_intel
>> drm_display_helper nvme crypto_simd usbcore cryptd cec ccp nvme_core
>> sp5100_tco rc_core amd_sfh video wmi btrfs blake2b_generic libcrc32c
>> crc32c_intel xor raid6_pq v4l2loopback(O) videodev mc sg dm_multipath dm_mod
>> scsi_dh_rdac scsi_dh_emc scsi_dh_alua msr efivarfs
>> Feb 15 08:44:49.840786 myhost kernel: CPU: 7 PID: 755 Comm: kworker/7:2
>> Tainted: G           O       6.1.10-1-default #1 openSUSE Tumbleweed
>> 22576c8b47239465c1855ce27337697dac36c24c
>> Feb 15 08:44:49.840809 myhost kernel: Hardware name: GIGABYTE
>> GB-BRR7H-4800/GB-BRR7H-4800, BIOS F5 05/05/2021
>> Feb 15 08:44:49.840827 myhost kernel: Workqueue: events
>> register_cache_worker [bcache]
>> Feb 15 08:44:49.840844 myhost kernel: RIP:
>> 0010:journal_read_bucket+0x3df/0x490 [bcache]
>> Feb 15 08:44:49.840860 myhost kernel: Code: 00 00 00 48 89 ee 48 c7 c2 70 c4
>> cb c0 48 c7 c7 a8 c4 cb c0 4c 89 5c 24 48 48 89 44 24 20 c6 05 21 c8 02 00
>> 01 e8 3e f5 65 f1 <0f> 0b 4c 8b 5c 24 48 48 8b 44 24 20 e9 6b ff ff ff 44 8b
>> 74 24 54
>> Feb 15 08:44:49.840884 myhost kernel: RSP: 0018:ffffb6fe01893c98 EFLAGS:
>> 00010282
>> Feb 15 08:44:49.840900 myhost kernel: RAX: 0000000000000000 RBX:
>> ffff95ebc2a3c000 RCX: 0000000000000027
>> Feb 15 08:44:49.840915 myhost kernel: RDX: ffff95f2af7e24e8 RSI:
>> 0000000000000001 RDI: ffff95f2af7e24e0
>> Feb 15 08:44:49.840932 myhost kernel: RBP: 0000000000000108 R08:
>> 0000000000000000 R09: ffffb6fe01893b40
>> Feb 15 08:44:49.840948 myhost kernel: R10: 0000000000000003 R11:
>> ffff95f2cf2ff228 R12: dead000000000122
>> Feb 15 08:44:49.840965 myhost kernel: R13: dead000000000100 R14:
>> ffff95ebc46a8400 R15: ffffb6fe01893e08
>> Feb 15 08:44:49.840981 myhost kernel: FS:  0000000000000000(0000)
>> GS:ffff95f2af7c0000(0000) knlGS:0000000000000000
>> Feb 15 08:44:49.840998 myhost kernel: CS:  0010 DS: 0000 ES: 0000 CR0:
>> 0000000080050033
>> Feb 15 08:44:49.841014 myhost kernel: CR2: 00007f166249afe0 CR3:
>> 000000010323e000 CR4: 0000000000350ee0
>> Feb 15 08:44:49.841030 myhost kernel: Call Trace:
>> Feb 15 08:44:49.841047 myhost kernel:  <TASK>
>> Feb 15 08:44:49.841067 myhost kernel:  ? bch_btree_exit+0x20/0x20 [bcache
>> f7676faef63111511583961fa9b18ec07deb88c4]
>> Feb 15 08:44:49.841090 myhost kernel:  bch_journal_read+0x79/0x320 [bcache
>> f7676faef63111511583961fa9b18ec07deb88c4]
>> Feb 15 08:44:49.841108 myhost kernel: register_cache_worker+0x99f/0x11c0
>> [bcache f7676faef63111511583961fa9b18ec07deb88c4]
>> Feb 15 08:44:49.841125 myhost kernel:  ?
>> finish_task_switch.isra.0+0x90/0x2d0
>> Feb 15 08:44:49.841141 myhost kernel:  process_one_work+0x20c/0x3d0
>> Feb 15 08:44:49.841157 myhost kernel:  worker_thread+0x4a/0x3b0
>> Feb 15 08:44:49.841173 myhost kernel:  ? process_one_work+0x3d0/0x3d0
>> Feb 15 08:44:49.841188 myhost kernel:  kthread+0xd7/0x100
>> Feb 15 08:44:49.841203 myhost kernel:  ? kthread_complete_and_exit+0x20/0x20
>> Feb 15 08:44:49.841219 myhost kernel:  ret_from_fork+0x1f/0x30
>> Feb 15 08:44:49.841236 myhost kernel:  </TASK>
>> Feb 15 08:44:49.841251 myhost kernel: ---[ end trace 0000000000000000 ]---
>> Feb 15 08:44:49.848553 myhost kernel: sr 1:0:0:0: [sr0] scsi3-mmc drive:
>> 24x/24x writer dvd-ram cd/rw xa/form2 cdda tray
>> Feb 15 08:44:49.848843 myhost kernel: cdrom: Uniform CD-ROM driver Revision:
>> 3.20
>> Feb 15 08:44:49.872544 myhost kernel: plantronics 0003:047F:1200.0004:
>> input,hiddev96,hidraw3: USB HID v1.11 Device [Plantronics Plantronics
>> Calisto 7200] on usb-0000:04:00.0-2.4/input3
>> Feb 15 08:44:49.876547 myhost kernel: sr 1:0:0:0: Attached scsi CD-ROM sr0
>> Feb 15 08:44:49.880540 myhost kernel: ------------[ cut here ]------------