From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AEFB6C33CAB for ; Mon, 13 Jan 2020 01:34:41 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5925721556 for ; Mon, 13 Jan 2020 01:34:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5925721556 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A9EF58E0005; Sun, 12 Jan 2020 20:34:40 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A4FDC8E0001; Sun, 12 Jan 2020 20:34:40 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 93DED8E0005; Sun, 12 Jan 2020 20:34:40 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0199.hostedemail.com [216.40.44.199]) by kanga.kvack.org (Postfix) with ESMTP id 7D0B28E0001 for ; Sun, 12 Jan 2020 20:34:40 -0500 (EST) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id 13335180AD817 for ; Mon, 13 Jan 2020 01:34:40 +0000 (UTC) X-FDA: 76370891520.09.fruit47_28b2f4c9d0c2f X-HE-Tag: fruit47_28b2f4c9d0c2f X-Filterd-Recvd-Size: 2661 Received: from gentwo.org (gentwo.org [3.19.106.255]) by imf38.hostedemail.com (Postfix) with ESMTP for ; Mon, 13 Jan 2020 01:34:39 +0000 (UTC) Received: by gentwo.org (Postfix, from userid 1002) id EEB3C3ED6B; Mon, 13 Jan 2020 01:34:38 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by gentwo.org (Postfix) with ESMTP id ED43E3ED4F; Mon, 13 Jan 2020 01:34:38 +0000 (UTC) Date: Mon, 13 Jan 2020 01:34:38 +0000 (UTC) From: Christopher Lameter X-X-Sender: cl@www.lameter.com To: Tetsuo Handa cc: Vlastimil Babka , Yu Zhao , Andrew Morton , Pekka Enberg , David Rientjes , Joonsoo Kim , "Kirill A . Shutemov" , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A . Shutemov" Subject: Re: [FIX] slub: Remove kmalloc under list_lock from list_slab_objects() V2 In-Reply-To: Message-ID: References: <20191108193958.205102-1-yuzhao@google.com> <20191108193958.205102-2-yuzhao@google.com> <20191109230147.GA75074@google.com> <20191110184721.GA171640@google.com> <20191130150908.06b2646edfa7bdc12a943c25@linux-foundation.org> <20191207220320.GA67512@google.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, 12 Jan 2020, Tetsuo Handa wrote: > On 2020/01/10 23:11, Vlastimil Babka wrote: > Hmm, this one? Even non-ML destinations are sometimes rejected (e.g. > 554 5.7.1 Service unavailable; Client host [202.181.97.72] blocked using b.barracudacentral.org; http://www.barracudanetworks.com/reputation/?pr=1&ip=202.181.97.72 > ). Anyway, I just worried whether it is really safe to do memory allocation > which might involve memory reclaim. You MM guys know better... We are talking about a call to destroy the kmem_cache. This is not done under any lock. The lock was taken inside that function before the call to list_slab_objects. That can be avoided.