[PATCH v3 2/2] mm, hwpoison: When copy-on-write hits poison, take page offline

[Miaohe Lin]

On 2022/10/29 0:13, Luck, Tony wrote:
>>> Cannot call memory_failure() directly from the fault handler because
>>> mmap_lock (and others) are held.
>>
>> Could you please explain which lock makes it unfeasible to call memory_failure() directly and
>> why? I'm somewhat confused. But I agree using memory_failure_queue() should be a good idea.
> 
> I tried calling memory_failure() directly, and my system just hung. I made the assumption
> that it had deadlocked based somewhat on the comments in mm/memory.c about mmap_lock
> being held ... but I didn't dig into what had gone wrong.

I see. Thanks for your explanation. :)

> 
> -Tony
>