Re: [PATCH 2/2] mm/hugetlb: fix unable to handle page fault for address dead000000000108

[Miaohe Lin <linmiaohe@huawei.com>]

On 2024/4/19 4:38, Andrew Morton wrote:
> On Thu, 18 Apr 2024 10:20:00 +0800 Miaohe Lin <linmiaohe@huawei.com> wrote:
> 
>> Below panic occurs when I did memory failure test:
>>
>> BUG: unable to handle page fault for address: dead000000000108
>>
>> ...
>>
>> The root cause is that list_del() is used to remove folio from list when
>> dissolve_free_hugetlb_folio(). But list_move() might be used to reenqueue
>> hugetlb folio when free_huge_folio() leading to above panic. Fix this
>> issue by using list_del_init() to remove folio.
>>
>> ...
>>
>> --- a/mm/hugetlb.c
>> +++ b/mm/hugetlb.c
>> @@ -1642,7 +1642,7 @@ static void __remove_hugetlb_folio(struct hstate *h, struct folio *folio,
>>  	if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
>>  		return;
>>  
>> -	list_del(&folio->lru);
>> +	list_del_init(&folio->lru);
>>  
>>  	if (folio_test_hugetlb_freed(folio)) {
>>  		h->free_huge_pages--;
> 
> We should cc:stable and find a Fixes:.  This appears to predate
> 6eb4e88a6d27022ea8aff424d47a0a5dfc9fcb34, after which I got lost.

It's weird I didn't observe this issue before last merge window while corresponding
code logic seems not changed. I will try again to find a Fixes.
Thanks.
.

> .
>