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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 34FBEC43334 for ; Mon, 20 Jun 2022 09:24:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239987AbiFTJY0 (ORCPT ); Mon, 20 Jun 2022 05:24:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34446 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233274AbiFTJYX (ORCPT ); Mon, 20 Jun 2022 05:24:23 -0400 Received: from mail-pj1-x102f.google.com (mail-pj1-x102f.google.com [IPv6:2607:f8b0:4864:20::102f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A037D11814 for ; Mon, 20 Jun 2022 02:24:22 -0700 (PDT) Received: by mail-pj1-x102f.google.com with SMTP id hv24-20020a17090ae41800b001e33eebdb5dso11728528pjb.0 for ; Mon, 20 Jun 2022 02:24:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=szD84NW83cVtv82n5OVU6Bl02EDL48mPjF9aZDZgfQ0=; b=hKoNa3smMjr3Cp/1VKLsnoYUtQ8+HULkfzWUN/+B9vHKdAS09tXTG4QiudHlCorN77 y6d6ugEWIdyXJHaBge9HAmMopS6lQUgj/RggPhMK2og+Ie1qOdzUne1MkzazXSCCTc4J 7MTY31EcD38O9NEexFqJrGqAIW2XdIVPdlcI0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=szD84NW83cVtv82n5OVU6Bl02EDL48mPjF9aZDZgfQ0=; b=XrYLDQE1YGyXk2dr9XZSQE26AMFmDFvGJQgi35fx1UrWEnXepgBORrx7AbvFi0EA73 rBmbffCEIBsExU/KGMCKvDnsSLAzN8Xd8IYIylPmNCrGT65JUoH39AB0BaWGX/zVERky uJ1OsYl4e0DeLhALano2xLVr1CPLoBqj5wqJ5O7n/MmZ//g5npQKeFEGRtRwrkGwhiv3 j5jKM58KEvsd10ZMRAAlszVKk+QMMykOU8KgnKNLGdsjvQpC5zpPCoVhWXvyCzcA87NE dpnnEbVvtI76YDmQLHBYnvHSuWTyTT851npKgLMHdVr1ZCnsfok8xccbJ1BbgCUIlzV4 VkAg== X-Gm-Message-State: AJIora+RQaokRPUSXm6RfNETtohilW1jsaaY9IxbdM8BRVB5jvcXIlGQ sZa5IipTMTCp6KK1T/+ehCIqGJtkzwtRIA== X-Google-Smtp-Source: AGRyM1tM0BOvsvYZnqUzt6qkw0KDqrbe+a0xJSkBjPzhfBacxW6h+Kji+ZNJJbrTSlvA1vUv0fPzQQ== X-Received: by 2002:a17:90b:48cf:b0:1e8:9438:ce13 with SMTP id li15-20020a17090b48cf00b001e89438ce13mr25758776pjb.235.1655717062022; Mon, 20 Jun 2022 02:24:22 -0700 (PDT) Received: from google.com ([240f:75:7537:3187:7080:f919:392f:bc5c]) by smtp.gmail.com with ESMTPSA id l4-20020a170903120400b001638a171558sm8205254plh.202.2022.06.20.02.24.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Jun 2022 02:24:21 -0700 (PDT) Date: Mon, 20 Jun 2022 18:24:15 +0900 From: Sergey Senozhatsky To: Dmitry Vyukov Cc: Sergey Senozhatsky , syzbot , akpm@linux-foundation.org, glider@google.com, gregkh@linuxfoundation.org, jirislaby@kernel.org, john.ogness@linutronix.de, linux-kernel@vger.kernel.org, npiggin@gmail.com, pmladek@suse.com, rdunlap@infradead.org, rostedt@goodmis.org, swboyd@chromium.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] possible deadlock in console_lock_spinning_enable (2) Message-ID: References: <0000000000007ba8cd05d0c1c3b0@google.com> <00000000000071951f05e1c4d7c8@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (22/06/20 10:16), Dmitry Vyukov wrote: > On Mon, 20 Jun 2022 at 07:44, Sergey Senozhatsky > wrote: > > > > On (22/06/18 20:47), syzbot wrote: > > > syzbot suspects this issue was fixed by commit: > > > > > > commit faebd693c59387b7b765fab64b543855e15a91b4 > > > Author: John Ogness > > > Date: Thu Apr 21 21:22:36 2022 +0000 > > > > > > printk: rename cpulock functions > > > > I'd rather guess that it was console kthread patch that fixed the problem. > > Hi Sergey, > > Do you mean this commit: > > author: John Ogness 2022-04-21 23:28:48 +0206 > printk: add kthread console printers > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=09c5ba0aa2fcfdadb17d045c3ee6f86d69270df7 Yes, I'd assume so. The patch removes tty -> printk -> tty which re-enters tty in unsafe manner, and replaces it with tty -> printk -> wake_up console printer