Re: [PATCH 2/3] spi: pxa2xx: Fix controller unregister order

[Tsuchiya Yuto <kitakar@xxxxxxxxx>]

Correction (obvious but just in case)

On 5/27/20 10:14 PM, Tsuchiya Yuto wrote:
>
> On 5/27/20 9:27 PM, Andy Shevchenko wrote:
>> On Wed, May 27, 2020 at 09:09:17PM +0900, Tsuchiya Yuto wrote:
>>> [...]
>>>
>>> I also built a kernel against your branch topic/spi/reload
>>> (permalink: https://github.com/andy-shev/linux/tree/55cb78d5a752). The
>>> result is the same as only applying this series; so, to fix the NULL pointer
>>> dereference that I mentioned in bugzilla [2], only this series is required.

*I also built a kernel from your branch topic/spi/reload

>>> Also, I want to make sure that what you tried in that branch is fixing
>>> the NULL pointer dereference on spi_pxa2xx_platform module removal when
>>> touch input crashed, not fixing the touch input crashing itself?
>>
>> Yes, my aim was to fix the SPI module reload issue. While the applied patch
>> from Lukas does a huge improvement, there are still issues with ordering (you
>> probably will never see them, though it's still possible based on the code).
>>
>> So, as far as I understood, the touch still able to come into position where
>> it's not anymore responsive. Is it correct?
>
> Yes, the touch still able to come into non-working state after every s2idle,
> but always can be resurrected by reloading spi_pxa2xx_platform.

This is true for both this series and branch topic/spi/reload

> What this series fixed is the following thing:
> - without this series: reloading spi_pxa2xx_platform resurrects touch
>   input with causing NULL pointer dereference (system still operational
>   after this anyway)
> - with this series: reloading spi_pxa2xx_platform resurrects touch input
>   *without* causing NULL pointer dereference
>
> Let me know if any further info is required.

*What this series (and branch topic/spi/reload) fixed is the following thing:

>>> [1] https://bugzilla.kernel.org/show_bug.cgi?id=206403
>>> [2] https://bugzilla.kernel.org/show_bug.cgi?id=206403#c1