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=-3.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 C26EBC47420 for ; Wed, 30 Sep 2020 00:48:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5C15C2074F for ; Wed, 30 Sep 2020 00:48:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fHcGrnQk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729230AbgI3As6 (ORCPT ); Tue, 29 Sep 2020 20:48:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48120 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726806AbgI3As5 (ORCPT ); Tue, 29 Sep 2020 20:48:57 -0400 Received: from mail-pj1-x1042.google.com (mail-pj1-x1042.google.com [IPv6:2607:f8b0:4864:20::1042]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F5E5C061755 for ; Tue, 29 Sep 2020 17:48:56 -0700 (PDT) Received: by mail-pj1-x1042.google.com with SMTP id kk9so131996pjb.2 for ; Tue, 29 Sep 2020 17:48:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=jfDxSkmpPjqtsnMdFLpAkBQJrfG5Oh0rLzmY203/J8Q=; b=fHcGrnQkLaCp+GP2WXdS/8+17sMxE6Exgu/8HJoq8GDh/Eql+Lkf0WNyQGeD4bTKRo eLKMZlmMcovC3ncFDCH7+X6AqjWM3hfTOrT7IqMttOTvSWOv18wnyn8fQTj2Q1FHIZqZ FFVFz6JkUurMhciKXo7irkeSNXneQPsp9jOrhEt9qTvDlz6pvQWfqevJVS9nbpr0n8f7 xLZU3kY8aWrDTmL5Lg+n/IwG5JgDM1cyd/cTM9toTpxQD8hWsv7pOviLBbXI1OfC64W+ E54nMpWT7Ov+YZHEBHDj7afFLOEvxm9iHts7Yzz22RHGxTy/C/s1TAV0KbcEscoGSMrN n2NA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=jfDxSkmpPjqtsnMdFLpAkBQJrfG5Oh0rLzmY203/J8Q=; b=o8RNWtchtUyEUw3iCk1/Uu5sNBMJyJtnR6FbXkqsUQahP1tE/eCFI6BVesZXJn6/AJ hhcGq58FV+8+YtDsLNeU3GH/kuSigohPAqdG7NYiaOG4aJ4qeUI2Tou5eavcqMLu6X5G euZ3OTHIjopwEmIA7HP1wU95Z7s/fnI4Uu2U26AtLWKmWv/0yzPADGfliLIN4+ld8gpn rvgs6O4PCmG1ful848k0VRievyILgh3e4QfRne1yw+8NQ8frMpPXQgo/vl3UWkiVleo9 4q5t7K8s2A25KAIAUW6OUUljLWnT5fz2VBvh9VgDM5QjXw1xiUXlJRVTidmOYD/8wfs6 gGYg== X-Gm-Message-State: AOAM532xuT8Ufh7IO2JFOniQKReJSScNMQ0MicNjMpLt7dSbYNb1g1R/ ijtcJZG4y1X3QqjEc/2OnyA= X-Google-Smtp-Source: ABdhPJy9FBbKj5N52pO00whzAXKOxk2MPPEDOlfxBFIP2v8O6ew2JFpzwVY/2se0ETWEgL1lerE+vQ== X-Received: by 2002:a17:90a:14a4:: with SMTP id k33mr181739pja.236.1601426935677; Tue, 29 Sep 2020 17:48:55 -0700 (PDT) Received: from localhost ([2409:10:2e40:5100:6e29:95ff:fe2d:8f34]) by smtp.gmail.com with ESMTPSA id u2sm74238pji.50.2020.09.29.17.48.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 29 Sep 2020 17:48:54 -0700 (PDT) Date: Wed, 30 Sep 2020 09:48:52 +0900 From: Sergey Senozhatsky To: Peter Zijlstra Cc: Petr Mladek , Chengming Zhou , maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@linux.ie, daniel@ffwll.ch, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, sergey.senozhatsky@gmail.com, rostedt@goodmis.org, mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, songmuchun@bytedance.com, john.ogness@linutronix.de Subject: Re: [External] Re: [PATCH 2/2] sched: mark PRINTK_DEFERRED_CONTEXT_MASK in __schedule() Message-ID: <20200930004852.GA987@jagdpanzerIV.localdomain> References: <20200927161130.33172-1-zhouchengming@bytedance.com> <20200927161130.33172-2-zhouchengming@bytedance.com> <20200928073202.GA2611@hirez.programming.kicks-ass.net> <40ab934e-5b8b-735b-da65-3043efab9fdc@bytedance.com> <20200928090143.GA2628@hirez.programming.kicks-ass.net> <688eadd7-4ca3-3e32-3520-25977ff059a6@bytedance.com> <20200928102559.GF2611@hirez.programming.kicks-ass.net> <20200929142750.GT6442@alley> <20200929150933.GR2628@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200929150933.GR2628@hirez.programming.kicks-ass.net> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (20/09/29 17:09), Peter Zijlstra wrote: > > 2. The registration and unregistration of consoles should not longer > > be handled by console_lock (semaphore). It should be possible to > > call most consoles without a sleeping lock. It should remove all > > these deadlocks between printk() and scheduler(). > > I'm confused, who cares about registation? That only happens once at > boot, right? You can modprobe or rmmod (register/unregister) netconsole anytime, for example. -ss