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Date:   Wed, 7 Apr 2021 11:37:49 +0200
From:   Oscar Salvador <osalvador@suse.de>
To:     Michal Hocko <mhocko@suse.com>
Cc:     Mike Kravetz <mike.kravetz@oracle.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Roman Gushchin <guro@fb.com>,
        Shakeel Butt <shakeelb@google.com>,
        David Hildenbrand <david@redhat.com>,
        Muchun Song <songmuchun@bytedance.com>,
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        Miaohe Lin <linmiaohe@huawei.com>,
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        HORIGUCHI NAOYA <naoya.horiguchi@nec.com>,
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        Barry Song <song.bao.hua@hisilicon.com>,
        Will Deacon <will@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH v4 5/8] hugetlb: call update_and_free_page without
 hugetlb_lock
Message-ID: <20210407093744.GA11066@linux>
References: <20210405230043.182734-1-mike.kravetz@oracle.com>
 <20210405230043.182734-6-mike.kravetz@oracle.com>
 <20210407082744.GA10058@linux>
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On Wed, Apr 07, 2021 at 11:28:51AM +0200, Michal Hocko wrote:
> An emoty page_list? If yes then sure, this can happen but
> list_for_each_entry_safe will simply not iterate. Or what do you mean?

Yes, I meant page_list.
Yeah, I figured list_for_each_entry_safe() would simply not iterate but I
wondered whether we still want the spin_unlock()/spin_lock() in that case.

But probably not worth it adding more code, so it is fine.

Thanks
 
-- 
Oscar Salvador
SUSE L3