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=-2.3 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 5565BC433E1 for ; Thu, 4 Jun 2020 17:18:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 412A5208A7 for ; Thu, 4 Jun 2020 17:18:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730115AbgFDRSQ (ORCPT ); Thu, 4 Jun 2020 13:18:16 -0400 Received: from mx2.suse.de ([195.135.220.15]:33150 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730072AbgFDRSP (ORCPT ); Thu, 4 Jun 2020 13:18:15 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 71AA3ABC2; Thu, 4 Jun 2020 17:18:17 +0000 (UTC) Subject: Re: slub freelist issue / BUG: unable to handle page fault for address: 000000003ffe0018 To: Vegard Nossum , Kees Cook , Christoph Lameter , Andrew Morton Cc: Marco Elver , Waiman Long , LKML , Linux MM References: <4dc93ff8-f86e-f4c9-ebeb-6d3153a78d03@oracle.com> From: Vlastimil Babka Message-ID: <7839183d-1c0b-da02-73a2-bf5e1e8b02b9@suse.cz> Date: Thu, 4 Jun 2020 19:18:13 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.1 MIME-Version: 1.0 In-Reply-To: <4dc93ff8-f86e-f4c9-ebeb-6d3153a78d03@oracle.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/4/20 7:14 PM, Vegard Nossum wrote: > > Hi all, > > I ran into a boot problem with latest linus/master > (6929f71e46bdddbf1c4d67c2728648176c67c555) that manifests like this: Hi, what's the .config you use? > hpet0: 3 comparators, 64-bit 100.000000 MHz counter > clocksource: Switched to clocksource tsc-early > BUG: unable to handle page fault for address: 000000003ffe0018 > #PF: supervisor read access in kernel mode > #PF: error_code(0x0000) - not-present page > PGD 0 P4D 0 > Oops: 0000 [#1] SMP PTI > CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0+ #211 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > Ubuntu-1.8.2-1ubuntu1 04/01/2014 > RIP: 0010:kmem_cache_alloc+0x70/0x1d0 > Code: 00 00 4c 8b 45 00 65 49 8b 50 08 65 4c 03 05 6f cc e7 7e 4d 8b 20 > 4d 85 e4 0f 84 3d 01 00 00 8b 45 20 48 8b 7d 00 48 8d 4a 01 <49> 8b 1c > 04 4c 89 e0 65 48 0f c7 0f 0f 94 c0 84 c0 74 c5 8b 45 20 > RSP: 0000:ffffc90000013df8 EFLAGS: 00010206 > RAX: 0000000000000018 RBX: ffffffff81c49200 RCX: 0000000000000002 > RDX: 0000000000000001 RSI: 0000000000000dc0 RDI: 000000000002b300 > RBP: ffff88803e403d00 R08: ffff88803ec2b300 R09: 0000000000000001 > R10: 0000000000000dc0 R11: 0000000000000006 R12: 000000003ffe0000 > R13: ffffffff8110a583 R14: 0000000000000dc0 R15: ffffffff81c49a80 > FS: 0000000000000000(0000) GS:ffff88803ec00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 000000003ffe0018 CR3: 0000000001c0a001 CR4: 00000000003606f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > __trace_define_field+0x33/0xa0 > event_trace_init+0xeb/0x2b4 > tracer_init_tracefs+0x60/0x195 > ? register_tracer+0x1e7/0x1e7 > do_one_initcall+0x74/0x160 > kernel_init_freeable+0x190/0x1f0 > ? rest_init+0x9a/0x9a > kernel_init+0x5/0xf6 > ret_from_fork+0x35/0x40 > CR2: 000000003ffe0018 > ---[ end trace 707efa023f2ee960 ]--- > RIP: 0010:kmem_cache_alloc+0x70/0x1d0 > > Bisection gives me: > > commit 3202fa62fb43087387c65bfa9c100feffac74aa6 > Author: Kees Cook > Date: Wed Apr 1 21:04:27 2020 -0700 > > slub: relocate freelist pointer to middle of object > > Reverting these three commits fixes it: > > 3202fa62fb43087387c65bfa9c100feffac74aa6 slub: relocate freelist pointer > to middle of object > 89b83f282d8ba380cf2124f88106c57df49c538c slub: avoid redzone when > choosing freepointer location > cbfc35a48609ceac978791e3ab9dde0c01f8cb20 mm/slub: fix incorrect > interpretation of s->offset > > > Vegard >