Re: [PATCH] Revert "blk-mq: issue directly if hw queue isn't busy in case of 'none'"

From: Jens Axboe
Date: Tue Aug 28 2018 - 13:12:21 EST


On 8/28/18 11:01 AM, Ian W MORRISON wrote:
> On Wed, 29 Aug 2018 at 02:13, Jens Axboe <axboe@xxxxxxxxx> wrote:
>>
>> On 8/28/18 10:10 AM, Ian W MORRISON wrote:
>>> On Wed, 29 Aug 2018 at 02:09, Jens Axboe <axboe@xxxxxxxxx> wrote:
>>>>
>>>> On 8/28/18 10:07 AM, Ian W MORRISON wrote:
>>>>> On Wed, 29 Aug 2018 at 01:48, Jens Axboe <axboe@xxxxxxxxx> wrote:
>>>>>>
>>>>>> On 8/28/18 9:47 AM, Ian W MORRISON wrote:
>>>>>>> Kernel oops when booting on Bay and Cherry Trail devices
>>>>>>> such as Intel Compute Stick. Bisected as:
>>>>>>>
>>>>>>> commit 6ce3dd6eec11 ("blk-mq: issue directly if hw queue isn't busy in case of 'none'")
>>>>>>>
>>>>>>> This patch reverts the above commit.
>>>>>>
>>>>>> Did I miss the posting of that oops? Just curious where this is
>>>>>> going wrong. Not adverse to reverting, but I'd like to try to
>>>>>> understand the issue first.
>>>>>>
>>>>>> --
>>>>>> Jens Axboe
>>>>>>
>>>>>
>>>>> I've not been able to capture it however manually transcribing what is
>>>>> on the screen:
>>>>>
>>>>> mmc0: Got data interrupt 0x00000002 even though no data operation
>>>>>
>>>>> followed by:
>>>>>
>>>>> mmc0: sdhci: ============= SDHCI REGISTER DUMP ==============
>>>>>
>>>>> Do you want any specific register value or should I transcribe each
>>>>> (as I am working from an image taken at boot)?
>>>>
>>>> Just take a picture of the screen, that should be good enough.
>>>>
>>>> --
>>>> Jens Axboe
>>>>
>>>
>>> Attached as requested.
>>
>> Can you see if this patch helps?
>>
>> https://marc.info/?l=linux-mmc&m=153485326025301&w=2
>>
>> --
>> Jens Axboe
>>
>
> I confirm that the above patch works with commit 6ce3dd6eec11
> and removes the need for reverting it on eMMC based devices.
>
> Tested on Bay Trail, Cherry Trail (both now working) and Kaby Lake
> (not affected) devices.

Great, thanks for testing. Adrian, when is this going upstream?

--
Jens Axboe