[dm-devel] [PATCH] block: Fix a WRITE SAME BUG_ON

[zhangxiaoxu (A)]

ping.

On 1/24/2019 8:25 PM, John Dorminy wrote:
> Resending as plain text, apologies.
> 
> On Thu, Jan 24, 2019 at 1:23 PM John Dorminy <jdorminy at redhat.com> wrote:
>>
>> Adding dm-devel since it involves LVM.
>>
>> On Thu, Jan 24, 2019 at 1:14 PM Zhang Xiaoxu <zhangxiaoxu5 at huawei.com> wrote:
>>>
>>> If the lvm is stacked by different logical_block_size disks,
>>> when WRITE SAME on it, will bug_on:
>>>
>>> kernel BUG at drivers/scsi/sd.c:968!
>>> invalid opcode: 0000 [#1] SMP PTI
>>> CPU: 11 PID: 525 Comm: kworker/11:1H Tainted: G           O      5.0.0-rc3+ #2
>>> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014
>>> Workqueue: kblockd blk_mq_run_work_fn
>>> RIP: 0010:sd_init_command+0x7aa/0xdb0
>>> Code: 30 75 00 00 c7 85 44 01 00 00 18 00 00 00 0f 85 fa 04 00 00 48 83 c4 40 48
>>>        89 df 5b 5d 41 5c 41 5d 41 5e 41 5f e9 b6 ca fe ff <0f> 0b 41 bc 09
>>> RSP: 0018:ffffb55f80ddbca0 EFLAGS: 00010206
>>> RAX: 0000000000001000 RBX: ffff9ed23fb927a0 RCX: 000000000000f000
>>> RDX: ffff9ed23f0a8400 RSI: ffff9ed27bc79800 RDI: 0000000000000000
>>> RBP: ffff9ed23fb92680 R08: ffff9ed27c8c0000 R09: ffff9ed23fb927d8
>>> R10: 0000000000000000 R11: fefefefefefefeff R12: ffff9ed27bc79800
>>> R13: ffff9ed2787a0000 R14: ffff9ed27bdf3400 R15: ffff9ed23fb927a0
>>> FS:  0000000000000000(0000) GS:ffff9ed27c8c0000(0000) knlGS:0000000000000000
>>> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>>> CR2: 00007f6b14cf9341 CR3: 0000000069058000 CR4: 00000000000006e0
>>> Call Trace:
>>>   ? vp_notify+0x12/0x20
>>>   scsi_queue_rq+0x525/0xa30
>>>   blk_mq_dispatch_rq_list+0x8d/0x580
>>>   ? syscall_return_via_sysret+0x10/0x7f
>>>   ? elv_rb_del+0x1f/0x30
>>>   ? deadline_remove_request+0x55/0xc0
>>>   blk_mq_do_dispatch_sched+0x76/0x110
>>>   blk_mq_sched_dispatch_requests+0xf9/0x170
>>>   __blk_mq_run_hw_queue+0x51/0xd0
>>>   process_one_work+0x195/0x380
>>>   worker_thread+0x30/0x390
>>>   ? process_one_work+0x380/0x380
>>>   kthread+0x113/0x130
>>>   ? kthread_park+0x90/0x90
>>>   ret_from_fork+0x35/0x40
>>> Modules linked in: alloc(O+)
>>> ---[ end trace dc92ddeb2e6d1fe5 ]---
>>>
>>> The logical_block_size of the LVM is the max value of the sub disks,
>>> it maybe different with one of the sub disk. when WRITE SAME on the
>>> disk, it will BUG_ON when setup WRITE SAME cmd.
>>>
>>> Close WRITE_SAME feature on the LVM if it was stacked by different
>>> logical_block_size disk.
>>>
>>> Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5 at huawei.com>
>>> ---
>>>   block/blk-settings.c | 4 ++++
>>>   1 file changed, 4 insertions(+)
>>>
>>> diff --git a/block/blk-settings.c b/block/blk-settings.c
>>> index 3e7038e475ee..e1695155ad61 100644
>>> --- a/block/blk-settings.c
>>> +++ b/block/blk-settings.c
>>> @@ -537,6 +537,10 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
>>>                  }
>>>          }
>>>
>>> +       /* If the logical block size is different, forbid write same */
>>> +       if (t->logical_block_size != b->logical_block_size)
>>> +               t->max_write_same_sectors = 0;
>>> +
>>>          t->logical_block_size = max(t->logical_block_size,
>>>                                      b->logical_block_size);
>>>
>>> --
>>> 2.14.4
>>>
> 
> .
>