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From:   Bin Wang <wangbin224@huawei.com>
To:     <willy@infradead.org>
CC:     <akpm@linux-foundation.org>, <linux-kernel@vger.kernel.org>,
        <linux-mm@kvack.org>, <naoya.horiguchi@nec.com>,
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Subject: Re: Re: [PATCH] mm/hwpoison: dissolve error hugepages of file mapping
Date:   Fri, 16 Jul 2021 09:00:28 +0800
Message-ID: <20210716010028.1720-1-wangbin224@huawei.com>
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Hi Matthew,

On Thu, 15 Jul 2021 at 16:22:40 +0100, Matthew Wilcox wrote:
> How is that safe?  If you're going to dissolve the huge page, you
> need to figure out which subpage needs to have the HWPoison flag set.

Thanks for your review. The p that we pass to the __page_handle_poison()
is the error subpage. And we will move the HWPoison flag to subpage in
the dissolve_free_huge_page():

if (PageHWPoison(head) && page != head) {
	SetPageHWPoison(page);
	ClearPageHWPoison(head);
}

Thanks,
Bin Wang