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Subject: Re: [PATCH 2/2] mm/hugetlb: fix unable to handle page fault for
 address dead000000000108
To: Andrew Morton <akpm@linux-foundation.org>
CC: <muchun.song@linux.dev>, <david@redhat.com>, <vbabka@suse.cz>,
	<willy@infradead.org>, <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>
References: <20240418022000.3524229-1-linmiaohe@huawei.com>
 <20240418022000.3524229-3-linmiaohe@huawei.com>
 <20240418133817.afb65c8dcd11cfea7c686d25@linux-foundation.org>
From: Miaohe Lin <linmiaohe@huawei.com>
Message-ID: <2a7c22c6-edda-e113-4688-f728b4f2d65c@huawei.com>
Date: Fri, 19 Apr 2024 10:07:26 +0800
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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.
.

> .
>