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Date:   Mon, 9 May 2022 11:58:56 +0200
From:   Oscar Salvador <osalvador@suse.de>
To:     Miaohe Lin <linmiaohe@huawei.com>
Cc:     HORIGUCHI =?utf-8?B?TkFPWUEo5aCA5Y+jIOebtOS5nyk=?= 
        <naoya.horiguchi@nec.com>, David Hildenbrand <david@redhat.com>,
        Naoya Horiguchi <naoya.horiguchi@linux.dev>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Yang Shi <shy828301@gmail.com>,
        Muchun Song <songmuchun@bytedance.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH v1 0/4] mm, hwpoison: improve handling workload
 related to hugetlb and memory_hotplug
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On Mon, May 09, 2022 at 05:04:54PM +0800, Miaohe Lin wrote:
> >> So that leaves us with either
> >>
> >> 1) Fail offlining -> no need to care about reonlining
> 
> Maybe fail offlining will be a better alternative as we can get rid of many races
> between memory failure and memory offline? But no strong opinion. :)

If taking care of those races is not an herculean effort, I'd go with
allowing offlining + disallow re-onlining.
Mainly because memory RAS stuff.

Now, to the re-onlining thing, we'll have to come up with a way to check
whether a section contains hwpoisoned pages, so we do not have to go
and check every single page, as that will be really suboptimal.


-- 
Oscar Salvador
SUSE Labs