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Message-ID: <2cc44d0d-1ede-daca-30fd-d302f1537dfe@redhat.com>
Date:   Tue, 15 Feb 2022 16:06:07 +0100
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Subject: Re: [PATCH v2] mm: clean up hwpoison page cache page in fault path
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To:     Rik van Riel <riel@surriel.com>, linux-kernel@vger.kernel.org
Cc:     kernel-team@fb.com, linux-mm@kvack.org,
        Miaohe Lin <linmiaohe@huawei.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mel Gorman <mgorman@suse.de>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Matthew Wilcox <willy@infradead.org>
References: <20220212213740.423efcea@imladris.surriel.com>
 <2a881586-3f5e-c277-f373-a9014d631700@redhat.com>
 <63f930e411655a6ad37d4818d0ae19784c82f076.camel@surriel.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
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On 15.02.22 16:01, Rik van Riel wrote:
> On Tue, 2022-02-15 at 12:22 +0100, David Hildenbrand wrote:
>> On 13.02.22 03:37, Rik van Riel wrote:
>>> Sometimes the page offlining code can leave behind a hwpoisoned
>>> clean
>>> page cache page. This can lead to programs being killed over and
>>> over
>>> and over again as they fault in the hwpoisoned page, get killed,
>>> and
>>> then get re-spawned by whatever wanted to run them.
>>
>> Hi Rik,
>>
>> am I correct that you are only talking about soft offlining as
>> triggered
>> from mm/memory-failure.c, not page offlining as in memory offlining
>> mm/memory_hotunplug.c ?
> 
> That is correct in that I am talking only about memory-failure.c,
> however the code in memory-failure.c has both hard and soft
> offlining modes, and I suppose this patch covers both?
> 

Right, for hwpoison handling there is hard and soft offlining of pages
... maybe "hwpoison page offlining" would be clearer, not sure.

Thanks for clarifying!

-- 
Thanks,

David / dhildenb