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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 3470FC432C0 for ; Sun, 1 Dec 2019 15:21:34 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E74112053B for ; Sun, 1 Dec 2019 15:21:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="d7cigOdX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E74112053B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=alien8.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 7B7646B0003; Sun, 1 Dec 2019 10:21:33 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 768BF6B0005; Sun, 1 Dec 2019 10:21:33 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 62F376B0006; Sun, 1 Dec 2019 10:21:33 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0178.hostedemail.com [216.40.44.178]) by kanga.kvack.org (Postfix) with ESMTP id 4AB4E6B0003 for ; Sun, 1 Dec 2019 10:21:33 -0500 (EST) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id 02300180AD817 for ; Sun, 1 Dec 2019 15:21:32 +0000 (UTC) X-FDA: 76216936866.01.cover31_64bdd86748709 X-HE-Tag: cover31_64bdd86748709 X-Filterd-Recvd-Size: 5866 Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by imf06.hostedemail.com (Postfix) with ESMTP for ; Sun, 1 Dec 2019 15:21:32 +0000 (UTC) Received: from zn.tnic (p200300EC2F2CED0040BA74DAC07AD948.dip0.t-ipconnect.de [IPv6:2003:ec:2f2c:ed00:40ba:74da:c07a:d948]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 9C8521EC05B5; Sun, 1 Dec 2019 16:21:26 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1575213686; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=0MYkPXxBScIuVqANywpZnamVKYDdtJxtOSaWBIRkFKI=; b=d7cigOdXLuITX03Q9o7+t/ZYQ3DnBwTrx5kun0lC3fIrbW6FHRBVBkC9B1rFVNNm7pzw+Q AD8rojlSAZLzf8H6BPGZ6ztx6CpGueksbxKxWpw5psixvZGbPDQOZ7e6bcOj1GG883Cvjh ZTz6dz6JNe/L5rkkSQ3gw3PPEOpglXs= Date: Sun, 1 Dec 2019 16:21:19 +0100 From: Borislav Petkov To: Linus Torvalds Cc: Andrew Morton , alex@ghiti.fr, aou@eecs.berkeley.edu, Ard Biesheuvel , Arnd Bergmann , Andrey Ryabinin , Benjamin Herrenschmidt , Christian Borntraeger , Qian Cai , Catalin Marinas , Dave Hansen , dave.jiang@intel.com, David Miller , Dmitry Vyukov , Alexander Potapenko , Vasily Gorbik , Heiko Carstens , Peter Anvin , James Morse , James Hogan , Kan Liang , Linux-MM , Russell King - ARM Linux , Andrew Lutomirski , Mark Rutland , mawilcox@microsoft.com, Ingo Molnar , mm-commits@vger.kernel.org, Michael Ellerman , n-horiguchi@ah.jp.nec.com, Palmer Dabbelt , Paul Burton , Paul Walmsley , Paul Mackerras , Peter Zijlstra , ralf@linux-mips.org, shashim@codeaurora.org, Steven Price , Thomas Gleixner , vgupta@synopsys.com, Will Deacon , zong.li@sifive.com Subject: Re: [patch 064/158] mm: add generic ptdump Message-ID: <20191201152119.GD6629@zn.tnic> References: <20191201015304.cRPsmKUTM%akpm@linux-foundation.org> <20191201090724.GA6629@zn.tnic> <20191201151010.GC6629@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20191201151010.GC6629@zn.tnic> User-Agent: Mutt/1.10.1 (2018-07-13) 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, Dec 01, 2019 at 04:10:11PM +0100, Borislav Petkov wrote: > So lemme first confirm it really is caused by those patches. Yeah, those patches are causing it. Tried your current master - it is OK - and then applied Andrew's patches I was CCed on, ontop, and I got in a VM: VFS: Mounted root (ext4 filesystem) readonly on device 8:2. devtmpfs: mounted Freeing unused kernel image (initmem) memory: 664K Write protecting kernel text and read-only data: 18164k NX-protecting the kernel data: 7416k BUG: kernel NULL pointer dereference, address: 00000014 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page *pdpt = 0000000000000000 *pde = f000ff53f000ff53 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.4.0+ #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.1-1 04/01/2014 EIP: __lock_acquire.isra.0+0x2e8/0x4e0 Code: e8 bd a1 2f 00 85 c0 74 11 8b 1d 08 8f 26 c5 85 db 0f 84 05 1a 00 00 8d 76 00 31 db 8d 65 f4 89 d8 5b 5e 5f 5d c3 8d 74 26 00 <8b> 44 90 04 85 c0 0f 85 4c fd ff ff e9 33 fd ff ff 8d b4 26 00 00 EAX: 00000010 EBX: 00000010 ECX: 00000001 EDX: 00000000 ESI: f1070040 EDI: f1070040 EBP: f1073e04 ESP: f1073de0 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010097 CR0: 80050033 CR2: 00000014 CR3: 05348000 CR4: 001406b0 Call Trace: lock_acquire+0x42/0x60 ? __walk_page_range+0x4d9/0x590 _raw_spin_lock+0x22/0x40 ? __walk_page_range+0x4d9/0x590 __walk_page_range+0x4d9/0x590 walk_page_range_novma+0x57/0xa0 ptdump_walk_pgd+0x38/0x70 ptdump_walk_pgd_level_core+0x66/0x90 ? ptdump_walk_pgd_level_core+0x90/0x90 ptdump_walk_pgd_level_checkwx+0x16/0x19 mark_rodata_ro+0x95/0x9a ? rest_init+0xfb/0xfb kernel_init+0x25/0xe5 ret_from_fork+0x2e/0x38 Modules linked in: CR2: 0000000000000014 ---[ end trace 8b67ede738f0029a ]--- EIP: __lock_acquire.isra.0+0x2e8/0x4e0 Code: e8 bd a1 2f 00 85 c0 74 11 8b 1d 08 8f 26 c5 85 db 0f 84 05 1a 00 00 8d 76 00 31 db 8d 65 f4 89 d8 5b 5e 5f 5d c3 8d 74 26 00 <8b> 44 90 04 85 c0 0f 85 4c fd ff ff e9 33 fd ff ff 8d b4 26 00 00 EAX: 00000010 EBX: 00000010 ECX: 00000001 EDX: 00000000 ESI: f1070040 EDI: f1070040 EBP: f1073e04 ESP: f1073de0 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010097 CR0: 80050033 CR2: 00000014 CR3: 05348000 CR4: 001406b0 note: swapper/0[1] exited with preempt_count 1 Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 Kernel Offset: disabled ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 ]--- -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette