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=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 8B2F0C4363D for ; Fri, 25 Sep 2020 15:16:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 29C2620878 for ; Fri, 25 Sep 2020 15:16:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="XnALWWze"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="lLkjtey+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728858AbgIYPQi (ORCPT ); Fri, 25 Sep 2020 11:16:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32860 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728654AbgIYPQi (ORCPT ); Fri, 25 Sep 2020 11:16:38 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 80F3FC0613CE for ; Fri, 25 Sep 2020 08:16:38 -0700 (PDT) Date: Fri, 25 Sep 2020 17:16:35 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1601046997; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=inzqDMhBmBSxlPcAKUg/MVYBSwG+9w8tzql36Odi0CU=; b=XnALWWzeM5LatSIWYs3NRSq7gxmjlPe9ZTPc4UwppAVyyE6aA5l5sZh9MdHM5MHA5tYJdo kL/oKFsPmI8QkbkfS28DZwVjIZeH1OOzK+aOtRLn0x2/lYWSiST/huyY5qY0vv1efR0Iue tJuOB9uRKqFh9rUdY3f2ViUtu/Uq8rzrIUgV/wlTjgYxq/X6jBWehJO7Y9D01pOwB9XWnO V18iaLudKaK4UYyrc3thEm4e/aUWcQHBg4XogNzuR4/gOSEaZ4EJuRxcdiJIpsU8j/sfqC ou9BmL44QK3f/3Onp9k52JAIp7nl9cj0xQIIX+pmc3R+QQsA+CehbSUV+jfZeQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1601046997; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=inzqDMhBmBSxlPcAKUg/MVYBSwG+9w8tzql36Odi0CU=; b=lLkjtey+a99ByslDBbh5mQCxb27SaRPr5JM5dvcz1UzBiCy+5+uS8aTmt7ykX9uEy8rVas DLYqlMbMymcXk2DQ== From: Sebastian Andrzej Siewior To: Aaron Marcher Cc: linux-rt-users@vger.kernel.org Subject: Re: Debugging reboot freeze Message-ID: <20200925151635.dar46x7shgu4nqms@linutronix.de> References: <20200925095715.poa62noo7dq2zyyp@linux-8csb> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200925095715.poa62noo7dq2zyyp@linux-8csb> Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org On 2020-09-25 11:57:15 [+0200], Aaron Marcher wrote: > Hi, Hi, > When using the same kernel version without PREEMPT_RT, the issue does > not occur. > > Do you have any hints for further debugging? > Thank you very much in advance. - try a later kernel (v5.9) - implement ->write_atomic() and make sure the output goes to printk_emergency() (so the output hits the uart right away). - enable lockdep and check what explodes. > Regards, > Aaron Marcher Sebastian