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Shutemov" To: Alex Shi Cc: akpm@linux-foundation.org, mgorman@techsingularity.net, tj@kernel.org, hughd@google.com, khlebnikov@yandex-team.ru, daniel.m.jordan@oracle.com, yang.shi@linux.alibaba.com, willy@infradead.org, hannes@cmpxchg.org, lkp@intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, shakeelb@google.com, iamjoonsoo.kim@lge.com, richard.weiyang@gmail.com Subject: Re: [PATCH v16 07/22] mm/thp: remove code path which never got into Message-ID: <20200720084325.fb6apppq5kvnw5eo@box> References: <1594429136-20002-1-git-send-email-alex.shi@linux.alibaba.com> <1594429136-20002-8-git-send-email-alex.shi@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1594429136-20002-8-git-send-email-alex.shi@linux.alibaba.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jul 11, 2020 at 08:58:41AM +0800, Alex Shi wrote: > split_huge_page() will never call on a page which isn't on lru list, so > this code never got a chance to run, and should not be run, to add tail > pages on a lru list which head page isn't there. > > Although the bug was never triggered, it'better be removed for code > correctness. > > BTW, it looks better to have BUG() or soem warning set in the wrong s/soem/some/ > path, but the path will be changed in incomming new page isolation > func. So just save it here. Yeah, WARN() would be great. Otherwise I'm okay with the patch Reviewed-by: Kirill A. Shutemov -- Kirill A. Shutemov