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Date:   Fri, 19 Mar 2021 13:21:37 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Michal Hocko <mhocko@suse.com>,
        Hugh Dickins <hughd@google.com>,
        Zhou Guanghui <zhouguanghui1@huawei.com>,
        Zi Yan <ziy@nvidia.com>, Shakeel Butt <shakeelb@google.com>,
        Roman Gushchin <guro@fb.com>, linux-mm@kvack.org,
        cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel-team@fb.com
Subject: Re: [PATCH] mm: page_alloc: fix memcg accounting leak in speculative
 cache lookup
Message-ID: <20210319132137.GZ3420@casper.infradead.org>
References: <20210319071547.60973-1-hannes@cmpxchg.org>
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On Fri, Mar 19, 2021 at 03:15:47AM -0400, Johannes Weiner wrote:
> When the freeing of a higher-order page block (non-compound) races
> with a speculative page cache lookup, __free_pages() needs to leave
> the first order-0 page in the chunk to the lookup but free the buddy
> pages that the lookup doesn't know about separately.

Thanks.