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=-12.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 DAC09C433C1 for ; Thu, 25 Mar 2021 18:20:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6C888619FB for ; Thu, 25 Mar 2021 18:20:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6C888619FB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id CF3516B006C; Thu, 25 Mar 2021 14:20:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CA4076B006E; Thu, 25 Mar 2021 14:20:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B44746B0070; Thu, 25 Mar 2021 14:20:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0099.hostedemail.com [216.40.44.99]) by kanga.kvack.org (Postfix) with ESMTP id 96E4D6B006C for ; Thu, 25 Mar 2021 14:20:58 -0400 (EDT) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 564358248D52 for ; Thu, 25 Mar 2021 18:20:58 +0000 (UTC) X-FDA: 77959212996.26.188A6D1 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf01.hostedemail.com (Postfix) with ESMTP id C50A0500152A for ; Thu, 25 Mar 2021 18:20:54 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 6A3B5619C7; Thu, 25 Mar 2021 18:20:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616696452; bh=ZVUJNwmRK3ITpUwMjag8eZ3lFFHOkxQLXXyTtKEeFSM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mFOLm6J1bQbFjXDeGgIAs6fEy1sf13gWd0Yx/bFwn+wEBTtPcyKUR/28UM323TJ5i iWVIJpdUqLLoXV9aaNpohiPsZJjz1egoKcb7eNeuvD9ybJ1fuej/gPF6yBkFUtL+2Q 3gnScU1p4qUCUO3ghlXpdrB67fUSekyWs+749xaLXIZpEmJSA/LTO/zAnuTVaBp0HG 8C9qkLmOy17N/b9G6mRwSk5Y1oTQ/S5+t9/rF533uOHcvf4//31Wc65zie3pvMKhpU vrPqJyX7OEfZbUxLAXmtH0LfYEE/sNEMWM6EjV2hdf6cPdGML+21IH63otSzY+a9O0 fDemAKcNBuiuQ== Date: Thu, 25 Mar 2021 18:20:47 +0000 From: Will Deacon To: Dmitry Vyukov Cc: syzbot , kernel-team@android.com, Andrew Morton , LKML , Linux-MM , syzkaller-bugs , Linux ARM Subject: Re: [syzbot] BUG: soft lockup in do_wp_page (4) Message-ID: <20210325182046.GA15860@willie-the-truck> References: <000000000000ce4c9505bdd4a48f@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-Stat-Signature: chh7wyk1ku6gya5j4i3g6rbk55p75hb1 X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: C50A0500152A Received-SPF: none (kernel.org>: No applicable sender policy available) receiver=imf01; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616696454-174226 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 Thu, Mar 18, 2021 at 08:34:16PM +0100, Dmitry Vyukov wrote: > On Thu, Mar 18, 2021 at 8:31 PM syzbot > wrote: > > > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: bf152b0b Merge tag 'for_linus' of git://git.kernel.org/pub.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=17d5264ed00000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=2c9917c41f0bc04b > > dashboard link: https://syzkaller.appspot.com/bug?extid=0b036374a865ba0efa8e > > userspace arch: arm64 > > > > Unfortunately, I don't have any reproducer for this issue yet. > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: syzbot+0b036374a865ba0efa8e@syzkaller.appspotmail.com > > > > watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [syz-executor.1:3684] > > +Will, arm > > If I am reading this commit correctly, this is caused by: > > commit cae118b6acc309539b33339e846cbb19187c164c > Author: Will Deacon > Date: Wed Mar 3 13:49:27 2021 +0000 > arm64: Drop support for CMDLINE_EXTEND > > syzbot passes lots of critical things in CONFIG_CMDLINE: > https://github.com/google/syzkaller/blob/c3c81c94865791469d376eba84f4a2d7763d3f71/dashboard/config/linux/upstream-arm64-kasan.config#L495 > but also wants the bootloader args to be appended. > What is the way to do it now? For now, there isn't a way to do it with CONFIG_CMDLINE, so I think you can either: * Revert my patch for your kernels * Pass the arguments via QEMU's -append option * Take a look at one of the series which should hopefully add this functionality back (but with well-defined semantics) [1] [2] Sorry for the nuisance; I did try to fix this [3] but it's a bit of a mess. Will [1] https://lore.kernel.org/linux-arch/cover.1614705851.git.christophe.leroy@csgroup.eu/ [2] https://lore.kernel.org/linux-mips/20210308235319.2988609-2-danielwa@cisco.com/#t [3] https://lore.kernel.org/r/20210225125921.13147-1-will@kernel.org