On 12/17/18 4:49 PM, Jens Axboe wrote:
> On 12/17/18 4:27 PM, Jens Axboe wrote:
>> On 12/17/18 4:16 PM, Bart Van Assche wrote:
>>> On Mon, 2018-12-17 at 11:28 -0700, Jens Axboe wrote:
>>>> As I'm sure you're all aware, the merge window is coming up. This time
>>>> it happens to coincide with that is a holiday for most. My plan is to
>>>> send in an EARLY pull request to Linus, Thursday at the latest. If you're
>>>> sitting on anything that should go in with the initial merge, then I need
>>>> to have it ASAP.
>>>>
>>>> I'll do a later pull about a week in with things that were missed, but
>>>> I'm really hoping to make that fixes only. Any driver updates etc should
>>>> go in now.
>>>
>>> Hi Jens,
>>>
>>> If I run blktests/srp/002 against Linus' master branch then that test passes,
>>> no matter how many times I run that test. If I run that test against your
>>> for-next branch however (commit 6a252f2772c0) then that test hangs. The output
>>> of my list-pending-block-requests script is as follows when the hang occurs:
>>
>> Ugh, I'll try and run that here again, that test is unfortunately such a pain
>> to run and requires me to manually install multipath libs (and remember to
>> uninstall before rebooting, or udev fails?).
>>
>> I'll take a look!
>
> Looks like what Ming was talking about. CC'ing Ming and Mike. Lots of
> kworkers are stuck like this:
>
> [ 252.310187] kworker/2:19 D14072 8147 2 0x80000000
> [ 252.316803] Workqueue: dio/dm-2 dio_aio_complete_work
> [ 252.322925] Call Trace:
> [ 252.326137] ? __schedule+0x231/0x5f0
> [ 252.330703] schedule+0x2a/0x80
> [ 252.334689] rwsem_down_write_failed+0x204/0x320
> [ 252.340330] ? generic_make_request_checks+0x55/0x370
> [ 252.346542] ? call_rwsem_down_write_failed+0x13/0x20
> [ 252.352669] call_rwsem_down_write_failed+0x13/0x20
> [ 252.358601] down_write+0x1b/0x30
> [ 252.362781] __generic_file_fsync+0x3e/0xb0
> [ 252.367933] ext4_sync_file+0xcc/0x2e0
> [ 252.372599] dio_complete+0x1c4/0x210
> [ 252.377168] process_one_work+0x1cb/0x350
> [ 252.382915] worker_thread+0x28/0x3c0
> [ 252.387482] ? process_one_work+0x350/0x350
> [ 252.392632] kthread+0x107/0x120
> [ 252.396717] ? kthread_park+0x80/0x80
> [ 252.401285] ret_from_fork+0x1f/0x30
>
> Where did this regression come from? This was passing just fine
> recently.
Looks like this is the offending commit:
commit c4576aed8d85d808cd6443bda58393d525207d01
Author: Mike Snitzer <snitzer@xxxxxxxxxx>
Date: Tue Dec 11 09:10:26 2018 -0500
dm: fix request-based dm's use of dm_wait_for_completion
--
Jens Axboe
