Re: LVM snapshot broke between 4.14 and 4.16

From: WGH
Date: Sat Aug 04 2018 - 16:32:00 EST


On 08/04/2018 08:04 PM, Linus Torvalds wrote:
> Anyway, just out of curiosity, what was the traceback?
>
> I'm not entirely happy with that patch either (even after the obvious
> fix to add the "1" argument), but it does seem like the minimal
> temporary workaround for now.

Here it is.

[ 68.313024] ------------[ cut here ]------------
[ 68.313030] dm-3
[ 68.313049] WARNING: CPU: 1 PID: 77 at block/blk-core.c:2180 generic_make_request_checks+0x4ac/0x600
[ 68.313054] Modules linked in: nf_tables xt_cgroup xt_owner kvm_intel iwlmvm kvm irqbypass iwlwifi
[ 68.313068] CPU: 1 PID: 77 Comm: kworker/1:1 Not tainted 4.17.9-gentoo #3
[ 68.313071] Hardware name: LENOVO 20B6A019RT/20B6A019RT, BIOS GJET91WW (2.41 ) 09/21/2016
[ 68.313077] Workqueue: ksnaphd do_metadata
[ 68.313083] RIP: 0010:generic_make_request_checks+0x4ac/0x600
[ 68.313087] RSP: 0018:ffffc900002e7ba8 EFLAGS: 00010282
[ 68.313091] RAX: 0000000000000000 RBX: ffff8801ef6da300 RCX: ffffffff82636218
[ 68.313094] RDX: 0000000000000001 RSI: 0000000000000086 RDI: ffffffff82cf57cc
[ 68.313097] RBP: ffff880211c2b150 R08: 0000000000000004 R09: 0000000000000307
[ 68.313100] R10: ffffc900002e7c80 R11: ffffffff82cf780d R12: 0000000000000000
[ 68.313103] R13: 0000000000000001 R14: 0000000000001000 R15: ffff8801ef6da300
[ 68.313107] FS: 0000000000000000(0000) GS:ffff88021f240000(0000) knlGS:0000000000000000
[ 68.313111] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 68.313114] CR2: 000056166d9e8520 CR3: 0000000003a0a006 CR4: 00000000001606e0
[ 68.313117] Call Trace:
[ 68.313126] ? scsi_init_sgtable+0x42/0x80
[ 68.313134] ? kmem_cache_alloc+0x170/0x1a0
[ 68.313140] generic_make_request+0x64/0x400
[ 68.313146] ? submit_bio+0x6c/0x140
[ 68.313150] ? bio_alloc_bioset+0xa9/0x1f0
[ 68.313155] submit_bio+0x6c/0x140
[ 68.313160] ? vm_get_page+0x20/0x50
[ 68.313165] dispatch_io+0x287/0x430
[ 68.313171] ? bio_next_page+0xb0/0xb0
[ 68.313175] ? bio_get_page+0x40/0x40
[ 68.313180] ? cpumask_next+0x16/0x20
[ 68.313185] sync_io+0xc3/0x120
[ 68.313191] dm_io+0x1f8/0x220
[ 68.313196] ? bio_next_page+0xb0/0xb0
[ 68.313200] ? bio_get_page+0x40/0x40
[ 68.313204] ? cpumask_next+0x16/0x20
[ 68.313209] do_metadata+0x1d/0x30
[ 68.313216] process_one_work+0x1b9/0x3e0
[ 68.313222] worker_thread+0x2b/0x3c0
[ 68.313227] ? wq_update_unbound_numa+0x10/0x10
[ 68.313232] kthread+0x113/0x130
[ 68.313237] ? kthread_create_worker_on_cpu+0x70/0x70
[ 68.313242] ret_from_fork+0x35/0x40
[ 68.313246] Code: 3e fc ff ff 45 8b a4 24 4c 03 00 00 48 8d 74 24 08 48 89 df c6 05 3a 49 35 01 01 e8 df 68 01 00 48 89 c7 44 89 e6 e8 c4 a0 cd ff <0f> 0b 4c 8b 63 08 e9 0c fc ff ff 80 3d 18 49 35 01 00 0f 85 29
[ 68.313300] ---[ end trace 2a4da4181ebee969 ]---