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Message-ID: <28aa571b-6dba-feb0-b888-4d18c9b0ffa1@suse.cz>
Date:   Fri, 11 Mar 2022 17:57:50 +0100
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Subject: Re: [PATCH] mm/page_alloc: check high-order pages for corruption
 during PCP operations
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To:     Mel Gorman <mgorman@techsingularity.net>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     Eric Dumazet <edumazet@google.com>,
        Eric Dumazet <eric.dumazet@gmail.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>, Michal Hocko <mhocko@kernel.org>,
        Shakeel Butt <shakeelb@google.com>,
        Wei Xu <weixugc@google.com>, Greg Thelen <gthelen@google.com>,
        Hugh Dickins <hughd@google.com>,
        David Rientjes <rientjes@google.com>
References: <20220310092456.GJ15701@techsingularity.net>
From:   Vlastimil Babka <vbabka@suse.cz>
In-Reply-To: <20220310092456.GJ15701@techsingularity.net>
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On 3/10/22 10:24, Mel Gorman wrote:
> Eric Dumazet pointed out that commit 44042b449872 ("mm/page_alloc: allow
> high-order pages to be stored on the per-cpu lists") only checks the head
> page during PCP refill and allocation operations. This was an oversight
> and all pages should be checked. This will incur a small performance
> penalty but it's necessary for correctness.
> 
> Fixes: 44042b449872 ("mm/page_alloc: allow high-order pages to be stored on the per-cpu lists")
> Reported-by: Eric Dumazet <edumazet@google.com>
> Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
> Acked-by: Eric Dumazet <edumazet@google.com>

Acked-by: Vlastimil Babka <vbabka@suse.cz>