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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 02F50C07E96 for ; Thu, 15 Jul 2021 16:22:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA1FD613F7 for ; Thu, 15 Jul 2021 16:22:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231200AbhGOQZY (ORCPT ); Thu, 15 Jul 2021 12:25:24 -0400 Received: from mail-out.m-online.net ([212.18.0.10]:54428 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229518AbhGOQZX (ORCPT ); Thu, 15 Jul 2021 12:25:23 -0400 Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 4GQflx2N84z1sFhS; Thu, 15 Jul 2021 18:22:21 +0200 (CEST) Received: from localhost (dynscan1.mnet-online.de [192.168.6.70]) by mail.m-online.net (Postfix) with ESMTP id 4GQflx1VZfz1qqkP; Thu, 15 Jul 2021 18:22:21 +0200 (CEST) X-Virus-Scanned: amavisd-new at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan1.mail.m-online.net [192.168.6.70]) (amavisd-new, port 10024) with ESMTP id 6d6OuwsxCZ1H; Thu, 15 Jul 2021 18:22:20 +0200 (CEST) X-Auth-Info: br3tlGgw4vIUf1Ch6+xeO/8ruM6sgiE8T8bKkq2wu8SAavokerfEAnRbwSVoSWqf Received: from igel.home (ppp-46-244-186-22.dynamic.mnet-online.de [46.244.186.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA; Thu, 15 Jul 2021 18:22:20 +0200 (CEST) Received: by igel.home (Postfix, from userid 1000) id 89C322C21E9; Thu, 15 Jul 2021 18:22:19 +0200 (CEST) From: Andreas Schwab To: Tong Tiangen Cc: , Paul Walmsley , Palmer Dabbelt , Albert Ou , , Subject: Re: [PATCH -next v2] riscv: add VMAP_STACK overflow detection References: <20210621032855.130650-1-tongtiangen@huawei.com> X-Yow: Sometime in 1993 NANCY SINATRA will lead a BLOODLESS COUP on GUAM!! Date: Thu, 15 Jul 2021 18:22:19 +0200 In-Reply-To: <20210621032855.130650-1-tongtiangen@huawei.com> (Tong Tiangen's message of "Mon, 21 Jun 2021 11:28:55 +0800") Message-ID: <87pmvjtumc.fsf@igel.home> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Jun 21 2021, Tong Tiangen wrote: > This patch adds stack overflow detection to riscv, usable when > CONFIG_VMAP_STACK=y. This breaks get_wchan: [ 65.609696] Unable to handle kernel paging request at virtual address ffffffd0003bbde8 [ 65.610460] Oops [#1] [ 65.610626] Modules linked in: virtio_blk virtio_mmio rtc_goldfish btrfs blake2b_generic libcrc32c xor raid6_pq sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua efivarfs [ 65.611670] CPU: 2 PID: 1 Comm: systemd Not tainted 5.14.0-rc1-1.g34fe32a-default #1 openSUSE Tumbleweed (unreleased) c62f7109153e5a0897ee58ba52393ad99b070fd2 [ 65.612334] Hardware name: riscv-virtio,qemu (DT) [ 65.613008] epc : get_wchan+0x5c/0x88 [ 65.613334] ra : get_wchan+0x42/0x88 [ 65.613625] epc : ffffffff800048a4 ra : ffffffff8000488a sp : ffffffd00021bb90 [ 65.614008] gp : ffffffff817709f8 tp : ffffffe07fe91b80 t0 : 00000000000001f8 [ 65.614411] t1 : 0000000000020000 t2 : 0000000000000000 s0 : ffffffd00021bbd0 [ 65.614818] s1 : ffffffd0003bbdf0 a0 : 0000000000000001 a1 : 0000000000000002 [ 65.615237] a2 : ffffffff81618008 a3 : 0000000000000000 a4 : 0000000000000000 [ 65.615637] a5 : ffffffd0003bc000 a6 : 0000000000000002 a7 : ffffffe27d370000 [ 65.616022] s2 : ffffffd0003bbd90 s3 : ffffffff8071a81e s4 : 0000000000003fff [ 65.616407] s5 : ffffffffffffc000 s6 : 0000000000000000 s7 : ffffffff81618008 [ 65.616845] s8 : 0000000000000001 s9 : 0000000180000040 s10: 0000000000000000 [ 65.617248] s11: 000000000000016b t3 : 000000ff00000000 t4 : 0c6aec92de5e3fd7 [ 65.617672] t5 : fff78f60608fcfff t6 : 0000000000000078 [ 65.618088] status: 0000000000000120 badaddr: ffffffd0003bbde8 cause: 000000000000000d [ 65.618621] [] get_wchan+0x5c/0x88 [ 65.619008] [] do_task_stat+0x7a2/0xa46 [ 65.619325] [] proc_tgid_stat+0xe/0x16 [ 65.619637] [] proc_single_show+0x46/0x96 [ 65.619979] [] seq_read_iter+0x190/0x31e [ 65.620341] [] seq_read+0xc4/0x104 [ 65.620633] [] vfs_read+0x6a/0x112 [ 65.620922] [] ksys_read+0x54/0xbe [ 65.621206] [] sys_read+0xe/0x16 [ 65.621474] [] ret_from_syscall+0x0/0x2 [ 65.622169] ---[ end trace f24856ed2b8789c5 ]--- [ 65.622832] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Andreas. -- Andreas Schwab, schwab@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."