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Date:   Sat, 21 Nov 2020 14:53:51 -0500
From:   Andrea Arcangeli <aarcange@redhat.com>
To:     Mel Gorman <mgorman@suse.de>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        Qian Cai <cai@lca.pw>
Cc:     Vlastimil Babka <vbabka@suse.cz>, Michal Hocko <mhocko@kernel.org>,
        David Hildenbrand <david@redhat.com>,
        linux-kernel@vger.kernel.org, Mike Rapoport <rppt@linux.ibm.com>,
        Baoquan He <bhe@redhat.com>
Subject: Re: [PATCH 1/1] mm: compaction: avoid fast_isolate_around() to set
 pageblock_skip on reserved pages
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 <20201121194506.13464-1-aarcange@redhat.com>
 <20201121194506.13464-2-aarcange@redhat.com>
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On Sat, Nov 21, 2020 at 02:45:06PM -0500, Andrea Arcangeli wrote:
> +					if (likely(!PageReserved(page)))

NOTE: this line will have to become "likely(page &&
!PageReserved(page))" to handle the case of non contiguous zones,
since pageblock_pfn_to_page might return NULL in that case.. I noticed
right after sending, but I'll wait some feedback before resending the
correction in case it gets fixed in another way.