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=-9.3 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FSL_HELO_FAKE,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1, USER_IN_DEF_DKIM_WL 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 39898C17443 for ; Sun, 10 Nov 2019 18:47:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 14712214E0 for ; Sun, 10 Nov 2019 18:47:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="T77cTQzB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727042AbfKJSr1 (ORCPT ); Sun, 10 Nov 2019 13:47:27 -0500 Received: from mail-io1-f66.google.com ([209.85.166.66]:34018 "EHLO mail-io1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726778AbfKJSr1 (ORCPT ); Sun, 10 Nov 2019 13:47:27 -0500 Received: by mail-io1-f66.google.com with SMTP id q83so11984901iod.1 for ; Sun, 10 Nov 2019 10:47:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=Ihq7lt4JbEWY+6wcZIMjCy2sGUa9cv1FuVr47U5+8AE=; b=T77cTQzBar9ULi4M3ndLSVhNCosWXGzTRsGB77e60yHLU89i55/ZoPV4lASEP4fZ5S UNGlHrBePOP28fLENE1BqS6l83VZhkIIfpg9Qon3vOsItveQhcTsrMCmczZJBJkpAVGM vn5Lwv7vCBatSN8Q9WSOKPjCuXSkLKGdoGdgRGs9h02v4JML4Q6KLocIwGdfKlYEcE9Y eyFB2cBrKhSlyQ9zceZbmxU54G3382lrEqFCat5J9rj8to7G+mrDcEIAzQspu8nD5GAX o38yTtoizmQiQHbi7byEyN0xhpJNxzu8UFKr1GTl3z8nVWYzANEQFF9O1iLEETyYnW3x 40IQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=Ihq7lt4JbEWY+6wcZIMjCy2sGUa9cv1FuVr47U5+8AE=; b=UYKnTwehXAP9rAoi989rllcrecMcygpul+ccvlNA0LMk0uTT3H3pay/F5ZaNC1qrvg bOkTOZBGeKJQ/+L2XHcOUGhHrZbXgAGF5C+sLJE5WvQdrc6cjYOlcTEuAcZ0ULGqpfDj Jy5ktW9jDQXi5/o7dExhk3T1p1HOg+dlLfx36eCgK2w/itCMREhnkzLxC1o8Kv5czN6L O8khL9A1NB3/g5vDF/Al1R9VzeBMltZ5ChdzXdhIiWfcDlFnsUZ/g+0Ahr8CUJlIpU/0 gwn0KgXMC5pa+E0tCPOAO4ZrJchYrt0BATLRMWMM6OetED6l+1Vx3AHGXQfnJEshb6LW Ofyg== X-Gm-Message-State: APjAAAUDMoHPOUsIgddiIDk4PLDCUvb7klaAFn1w/9mPYCk5phxujmzt eGzUfRTJoVOu8nwGXOjnGLYqHA== X-Google-Smtp-Source: APXvYqxLkoIQ3LUVM1Fqb7H2YFPYu78eeSDnBiTZ0MwnEwtPq05F0D0BEsTGr6kALLsT8iCxHxE/Dg== X-Received: by 2002:a05:6602:2429:: with SMTP id g9mr22152846iob.294.1573411646528; Sun, 10 Nov 2019 10:47:26 -0800 (PST) Received: from google.com ([2620:15c:183:0:9f3b:444a:4649:ca05]) by smtp.gmail.com with ESMTPSA id q69sm1745807ilb.4.2019.11.10.10.47.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 10 Nov 2019 10:47:25 -0800 (PST) Date: Sun, 10 Nov 2019 11:47:21 -0700 From: Yu Zhao To: Christopher Lameter Cc: Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , "Kirill A . Shutemov" , Tetsuo Handa , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A . Shutemov" Subject: Re: [PATCH v4 2/2] mm: avoid slub allocation while holding list_lock Message-ID: <20191110184721.GA171640@google.com> References: <20190914000743.182739-1-yuzhao@google.com> <20191108193958.205102-1-yuzhao@google.com> <20191108193958.205102-2-yuzhao@google.com> <20191109230147.GA75074@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Nov 09, 2019 at 11:16:28PM +0000, Christopher Lameter wrote: > On Sat, 9 Nov 2019, Yu Zhao wrote: > > > > struct page *page, *h; > > > + unsigned long *map = bitmap_alloc(oo_objects(s->max), GFP_KERNEL); > > > + > > > + if (!map) > > > + return; > > > > What would happen if we are trying to allocate from the slab that is > > being shut down? And shouldn't the allocation be conditional (i.e., > > only when CONFIG_SLUB_DEBUG=y)? > > Kmalloc slabs are never shut down. Maybe I'm not thinking straight -- isn't it what caused the deadlock in the first place? Kmalloc slabs can be shut down when memcg is on.