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Subject: Re: [PATCH] x86/process: Silence KASAN warnings in get_wchan()
To: Dmitry Vyukov <dvyukov@google.com>, Ingo Molnar <mingo@kernel.org>
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On 10/05/2015 02:39 PM, Dmitry Vyukov wrote:
>>
>> But that's all pretty disgusting really.
>>
>> Cannot we do better, such as annotating the function and then KASAN sorting out
>> its false positives, or something like that?
> 
> 
> We also plug __attribute__((no_sanitize_address)) on the function.
> 

It's absolutely unusable:( https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368
If we add it here, it won't built because of: '__always_inline __read_once_size()'

But, I think I have the solution.
We could have some blacklist - list of function names which we should be ignored.
In kasan_report() we could resolve return address to function name and compare it with name in list.
If name in list -> ignore report.