Re: [PATCH v4 1/3] mm/hwpoison: mf_mutex for soft offline and unpoison

From: Mike Kravetz
Date: Fri Jan 21 2022 - 13:59:52 EST


On 1/20/22 16:09, Mike Kravetz wrote:
> On 11/15/21 00:40, Naoya Horiguchi wrote:
>> From: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
>>
>> Originally mf_mutex is introduced to serialize multiple MCE events, but
>> it is not that useful to allow unpoison to run in parallel with memory_failure()
>> and soft offline. So apply mf_mutex to soft offline and unpoison.
>> The memory failure handler and soft offline handler get simpler with this.
>>

Sorry for the late question.

It is not directly part of this change, but can we also remove the check in
__soft_offline_page after this comment?

/*
* Check PageHWPoison again inside page lock because PageHWPoison
* is set by memory_failure() outside page lock. Note that
* memory_failure() also double-checks PageHWPoison inside page lock,
* so there's no race between soft_offline_page() and memory_failure().
*/

--
Mike Kravetz