Received: by 2002:a05:6a10:9e8c:0:0:0:0 with SMTP id y12csp52879pxx; Wed, 28 Oct 2020 17:56:15 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxkEJV3SMgvsKcGqtnOc+PexXbBtxG8SPwoAi7cpYfhkaGIxUxW+M8oeK3Wj1KU1/g3qii+ X-Received: by 2002:a05:6402:143:: with SMTP id s3mr1487337edu.267.1603932975643; Wed, 28 Oct 2020 17:56:15 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1603932975; cv=none; d=google.com; s=arc-20160816; b=ka1jBg6oCafoMGtrquX0Oha5pR5J/A01JRiOrAqDGP7IPqc2V1OCAxB3xEPkll4EUd QiHtP+HIYwqF3g/uwTOJkSJMOmWfPSMPNdd0onsumb5TQ/4jsdMkX3oft5clYIXhbGLc jPtfsIpEM9fCNM5cBEM4Ly8Z43A/w7XL9IGzo82IgHuHXXPAx9d69AdS3eiXb3kzVAPp AZ6XDIcHQIYDEg8d6xh8kU6doVHbfkmgQlRd4lvFWfSykRL9XhB3qoIdfAfmTitV2i36 EwC0K7iS8zThg3UiOUqvbST1Fnew90QU04u5HIW9kVogdOConZNiGxq+PNZDhB1QDBeq fdLA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:user-agent:references:message-id :in-reply-to:subject:cc:to:from:date; bh=VDEncW2GDeSot1PqlYBPKUW8Yhmpz4hExTRt7K+iq6s=; b=sAR2pnefmEAI/aZj89wkXjSSsxKMFdLQ4/MkSyzrg3GXr+CQdtduSMYKSmywfiDBY5 18XbTUtJfXoHVC4v6kyTbzWvKh/5nhWbwbLfkSIij4y6zOKU0HnrSii9i7L8wNJIoZc8 Upk8Rp98pJJ/1rRWb1dwEFwJkon+v9NIjBfX36EHuOy4tvxMyN+PkQGzAkamwC0vLQiP tP9Nmo3pmjINgekPz8f601uxZ797rhLidaWqI8UQ/ptHm9u7shSnSFWqi4IARwEBEchA 77ElOZ3czox6/ys2z7Rb6H+vnju3/6Su124/ZSD/78MhAngDetsnYi6w4P9hg58b4TYg i6Pg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id w14si866519edt.78.2020.10.28.17.55.54; Wed, 28 Oct 2020 17:56:15 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727305AbgJ1VsE (ORCPT + 99 others); Wed, 28 Oct 2020 17:48:04 -0400 Received: from gentwo.org ([3.19.106.255]:34068 "EHLO gentwo.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727781AbgJ1Vrw (ORCPT ); Wed, 28 Oct 2020 17:47:52 -0400 Received: by gentwo.org (Postfix, from userid 1002) id E4C6A3FCCF; Wed, 28 Oct 2020 11:11:20 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by gentwo.org (Postfix) with ESMTP id E14743F7B6; Wed, 28 Oct 2020 11:11:20 +0000 (UTC) Date: Wed, 28 Oct 2020 11:11:20 +0000 (UTC) From: Christopher Lameter X-X-Sender: cl@www.lameter.com To: Laurent Dufour cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, nathanl@linux.ibm.com, cheloha@linux.ibm.com, mhocko@suse.com, Vlastimil Babka , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , stable@vger.kernel.org Subject: Re: [PATCH v2] mm/slub: fix panic in slab_alloc_node() In-Reply-To: <20201027190406.33283-1-ldufour@linux.ibm.com> Message-ID: References: <7ef64e75-2150-01a9-074d-a754348683b3@suse.cz> <20201027190406.33283-1-ldufour@linux.ibm.com> User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 27 Oct 2020, Laurent Dufour wrote: > The issue is that object is not NULL while page is NULL which is odd but > may happen if the cache flush happened after loading object but before > loading page. Thus checking for the page pointer is required too. Ok then lets revert commit 6159d0f5c03e? The situation may occur elsewhere too.