Re: [PATCH v8 13/19] locking/rwsem: Make rwsem->owner an atomic_long_t

[Waiman Long]

On 7/21/19 4:49 PM, Luis Henriques wrote:
> Waiman Long <longman@xxxxxxxxxx> writes:
>
>> On 7/20/19 4:41 AM, Luis Henriques wrote:
>>> "Linus Torvalds" <torvalds@xxxxxxxxxxxxxxxxxxxx> writes:
>>>
>>>> On Fri, Jul 19, 2019 at 12:32 PM Waiman Long <longman@xxxxxxxxxx> wrote:
>>>>> This patch shouldn't change the behavior of the rwsem code. The code
>>>>> only access data within the rw_semaphore structures. I don't know why it
>>>>> will cause a KASAN error. I will have to reproduce it and figure out
>>>>> exactly which statement is doing the invalid access.
>>>> The stack traces should show line numbers if you run them through
>>>> scripts/decode_stacktrace.sh.
>>>>
>>>> You need to have debug info enabled for that, though.
>>>>
>>>> Luis?
>>>>
>>>>              Linus
>>> Yep, sure.  And I should have done this in the initial report.  It's a
>>> different trace, I had to recompile the kernel.
>>>
>>> (I'm also adding Jeff to the CC list.)
>>>
>>> Cheers,
>> Thanks for the information. I think I know where the problem is. Would
>> you mind applying the attached patch to see if it can fix the KASAN error.
> Yep, that seems to work -- I can't reproduce the error anymore (and
> sorry for the delay).  Thanks!  And feel free to add my Tested-by.
>
> Cheers,

Thanks for the testing. I will post the official patch tomorrow.

Cheers,
Longman