Re: [PATCH] mm/memory-failure: teach kill_accessing_process to accept hugetlb tail page pfn

[jane.chu@oracle.com]

On 12/20/2025 3:13 PM, Andrew Morton wrote:
> On Thu, 18 Dec 2025 23:28:19 -0700 Jane Chu <jane.chu@oracle.com> wrote:
> 
>> When a hugetlb folio is being poisoned again, try_memory_failure_hugetlb()
>> passed head pfn to kill_accessing_process(), that is not right.
>> The precise pfn of the poisoned page should be used in order to
>> determine the precise vaddr as the SIGBUS payload.
>>
>> This issue has already been taken care of in the normal path, that is,
>> hwpoison_user_mappings(), see [1][2].  Further more, for [3] to work
>> correctly in the hugetlb repoisoning case, it's essential to inform
>> VM the precise poisoned page, not the head page.
> 
> This conflicts with your "mm/memory-failure: fix missing ->mf_stats
> count in hugetlb poison".
> 
> Also conflicts a bit with "mm: fixup pfnmap memory failure handling to
> use pgoff" but that one isn't cc:stable, so this patch (which *is*
> cc:stable) takes priority.
> 
> Help?
> 

Sorry Andrew.  Let me try rebase v3 on top of my other patch.  Will also 
take a look at this other conflict.

thanks,
-jane