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 F12CAC43603 for ; Thu, 5 Dec 2019 12:30:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD5DA2464D for ; Thu, 5 Dec 2019 12:30:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729314AbfLEMac (ORCPT ); Thu, 5 Dec 2019 07:30:32 -0500 Received: from foss.arm.com ([217.140.110.172]:60952 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729117AbfLEMac (ORCPT ); Thu, 5 Dec 2019 07:30:32 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5C0E231B; Thu, 5 Dec 2019 04:30:31 -0800 (PST) Received: from arm.com (e112269-lin.cambridge.arm.com [10.1.194.43]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id ABE333F68E; Thu, 5 Dec 2019 04:30:30 -0800 (PST) Date: Thu, 5 Dec 2019 12:30:26 +0000 From: Steven Price To: Valdis =?utf-8?Q?Kl=C4=93tnieks?= Cc: Andrew Morton , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" Subject: Re: linux-next 20191204: crash in mm/pagewalk.c Message-ID: <20191205123025.GA46328@arm.com> References: <4587.1575548582@turing-police> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <4587.1575548582@turing-police> 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 Thu, Dec 05, 2019 at 12:23:02PM +0000, Valdis Klētnieks wrote: > linux-next 20191204 dies a horrid death on my laptop while booting: This is due to an unfortunate conflict between my series reworking of the page walk infrastructure to reuse it for kernel walks and a commit by Thomas Hellstrom to allow safe modification of entries in the callback. See [1] for more detail. I believe Andrew has dropped my series for now while I rework it to fix this conflict. Steve [1] https://lore.kernel.org/linux-arm-kernel/20191204163235.GA1597@arm.com/ > [ 12.344975] Write protecting the kernel read-only data: 26624k > [ 12.348497] Freeing unused kernel image (text/rodata gap) memory: 2036K > [ 12.349701] Freeing unused kernel image (rodata/data gap) memory: 1056K > [ 12.349756] BUG: kernel NULL pointer dereference, address: 0000000000000018 > [ 12.349810] #PF: supervisor read access in kernel mode > [ 12.349904] #PF: error_code(0x0000) - not-present page > [ 12.349920] PGD 0 P4D 0 > [ 12.349996] Oops: 0000 [#1] SMP > [ 12.350012] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G T 5.4.0-next-20191204-dirty #703 > [ 12.350031] Hardware name: TOSHIBA Satellite C55-B/ZBWAA, BIOS 5.00 07/23/2015 > [ 12.350055] RIP: 0010:__lock_acquire+0x465/0x810 > [ 12.350132] Code: 00 85 c0 74 10 44 8b 25 79 17 ba 01 45 85 e4 0f 84 c4 30 00 00 45 31 e4 48 83 c4 30 44 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 <49> 81 3e 60 32 0c 9d 41 ba 00 00 00 00 45 0f 45 d7 41 83 fc 01 0f > [ 12.350163] RSP: 0018:ffffb2f940053b70 EFLAGS: 00010002 > [ 12.350179] RAX: ffff8896c7d74040 RBX: 0000000000000000 RCX: 0000000000000000 > [ 12.350195] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000018 > [ 12.350211] RBP: ffffb2f940053bc8 R08: 0000000000000001 R09: 0000000000000000 > [ 12.350227] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 > [ 12.350305] R13: 0000000000000000 R14: 0000000000000018 R15: 0000000000000001 > [ 12.350323] FS: 0000000000000000(0000) GS:ffff8897f7a00000(0000) knlGS:0000000000000000 > [ 12.350340] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 12.350355] CR2: 0000000000000018 CR3: 0000000028a24000 CR4: 00000000001006f0 > [ 12.350370] Call Trace: > [ 12.350385] ? __bfs+0x2c/0x300 > [ 12.350404] lock_acquire+0x90/0x170 > [ 12.350421] ? walk_pgd_range+0x556/0x7b0 > [ 12.350441] _raw_spin_lock+0x31/0x70 > [ 12.350463] ? walk_pgd_range+0x556/0x7b0 > [ 12.350479] walk_pgd_range+0x556/0x7b0 > [ 12.350500] __walk_page_range+0x1a5/0x1c0 > [ 12.350517] ? __lock_acquired+0x1f8/0x310 > [ 12.350534] walk_page_range_novma+0x72/0xc0 > [ 12.350553] ptdump_walk_pgd+0x47/0x80 > [ 12.350570] ptdump_walk_pgd_level_core+0xc3/0xf0 > [ 12.350588] ? ptdump_walk_pgd_level_debugfs+0x30/0x30 > [ 12.350683] ? 0xffffffff9b000000 > [ 12.350699] ptdump_walk_pgd_level_checkwx+0x19/0x1b > [ 12.350717] mark_rodata_ro+0xc2/0xc9 > [ 12.350732] ? rest_init+0x2c1/0x2eb > [ 12.350747] kernel_init+0x3d/0x105 > [ 12.350761] ? rest_init+0x2eb/0x2eb > [ 12.350783] ret_from_fork+0x3a/0x50 > [ 12.350797] Modules linked in: > [ 12.350810] CR2: 0000000000000018 > [ 12.350822] ---[ end trace 5060898a61f6b985 ]--- > [ 12.424261] probe of 1-1 returned 1 after 1829 usecs > [ 12.453678] calling sdhci_drv_init+0x0/0x4a @ 1 > [ 12.527751] RIP: 0010:__lock_acquire+0x465/0x810 > [ 12.527771] Code: 00 85 c0 74 10 44 8b 25 79 17 ba 01 45 85 e4 0f 84 c4 30 00 00 45 31 e4 48 83 c4 30 44 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 <49> 81 3e 60 32 0c 9d 41 ba 00 00 00 00 45 0f 45 d7 41 83 fc 01 0f > [ 12.527792] RSP: 0018:ffffb2f940053b70 EFLAGS: 00010002 > [ 12.527803] RAX: ffff8896c7d74040 RBX: 0000000000000000 RCX: 0000000000000000 > [ 12.527814] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000018 > [ 12.527825] RBP: ffffb2f940053bc8 R08: 0000000000000001 R09: 0000000000000000 > [ 12.527836] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 > [ 12.527846] R13: 0000000000000000 R14: 0000000000000018 R15: 0000000000000001 > [ 12.527858] FS: 0000000000000000(0000) GS:ffff8897f7a00000(0000) knlGS:0000000000000000 > [ 12.527879] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 12.527894] CR2: 0000000000000018 CR3: 000000023060a000 CR4: 00000000001006f0 > [ 12.527911] Kernel panic - not syncing: Fatal exception >