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Subject: Re: [PATCH RESEND v6 3/9] mm: factor helpers for
 memory_failure_dev_pagemap
To:     Shiyang Ruan <ruansy.fnst@fujitsu.com>,
        linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org,
        nvdimm@lists.linux.dev, linux-mm@kvack.org,
        linux-fsdevel@vger.kernel.org, dm-devel@redhat.com
Cc:     djwong@kernel.org, dan.j.williams@intel.com, david@fromorbit.com,
        hch@lst.de, agk@redhat.com, snitzer@redhat.com
References: <20210730100158.3117319-1-ruansy.fnst@fujitsu.com>
 <20210730100158.3117319-4-ruansy.fnst@fujitsu.com>
From:   Jane Chu <jane.chu@oracle.com>
Organization: Oracle Corporation
Message-ID: <a5580cf5-9fcc-252d-5835-f199469516b0@oracle.com>
Date:   Thu, 5 Aug 2021 18:00:52 -0700
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On 7/30/2021 3:01 AM, Shiyang Ruan wrote:
> -	/*
> -	 * Prevent the inode from being freed while we are interrogating
> -	 * the address_space, typically this would be handled by
> -	 * lock_page(), but dax pages do not use the page lock. This
> -	 * also prevents changes to the mapping of this pfn until
> -	 * poison signaling is complete.
> -	 */
> -	cookie = dax_lock_page(page);
> -	if (!cookie)
> -		goto out;
> -
>   	if (hwpoison_filter(page)) {
>   		rc = 0;
> -		goto unlock;
> +		goto out;
>   	}

why isn't dax_lock_page() needed for hwpoison_filter() check?

thanks,
-jane