Date:   Tue, 21 Dec 2021 10:37:30 +0100
From:   Oscar Salvador <osalvador@suse.de>
To:     Liu Shixin <liushixin2@huawei.com>
Cc:     Naoya Horiguchi <naoya.horiguchi@nec.com>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH -next] mm/hwpoison: clear MF_COUNT_INCREASED before
 retrying get_any_page()
Message-ID: <20211221093730.GA14602@linux>
References: <20211221074908.3910286-1-liushixin2@huawei.com>
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On Tue, Dec 21, 2021 at 03:49:08PM +0800, Liu Shixin wrote:
> Hulk Robot reported a panic in put_page_testzero() when testing madvise()
> with MADV_SOFT_OFFLINE. The BUG() is triggered when retrying get_any_page().
> This is because we keep MF_COUNT_INCREASED flag in second try but the refcnt
> is not increased.
> 
[...]
> 
> Fixes: b94e02822deb ("mm,hwpoison: try to narrow window race for free pages")
> Reported-by: Hulk Robot <hulkci@huawei.com>
> Signed-off-by: Liu Shixin <liushixin2@huawei.com>

Reviewed-by: Oscar Salvador <osalvador@suse.de>


-- 
Oscar Salvador
SUSE Labs