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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 5154BC34026 for ; Tue, 18 Feb 2020 15:01:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2F6C12176D for ; Tue, 18 Feb 2020 15:01:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726717AbgBRPB0 (ORCPT ); Tue, 18 Feb 2020 10:01:26 -0500 Received: from bmailout1.hostsharing.net ([83.223.95.100]:52481 "EHLO bmailout1.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726667AbgBRPB0 (ORCPT ); Tue, 18 Feb 2020 10:01:26 -0500 Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.hostsharing.net", Issuer "COMODO RSA Domain Validation Secure Server CA" (not verified)) by bmailout1.hostsharing.net (Postfix) with ESMTPS id 3B2DA30004511; Tue, 18 Feb 2020 16:01:24 +0100 (CET) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 1084E14BA9C; Tue, 18 Feb 2020 16:01:24 +0100 (CET) Date: Tue, 18 Feb 2020 16:01:24 +0100 From: Lukas Wunner To: Nicholas Johnson Cc: Bjorn Helgaas , "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" Subject: Re: Stack trace when removing Thunderbolt devices while kernel shutting down Message-ID: <20200218150124.stvsj2rozxrgxw2h@wunner.de> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Tue, Feb 18, 2020 at 02:18:40PM +0000, Nicholas Johnson wrote: > If I surprise remove Thunderbolt 3 devices just as the kernel is > shutting down, I get stack dumps, when those devices would not normally > cause stack dumps if the kernel were not shutting down. > > Because the kernel is shutting down, it makes it difficult to capture > the logs without a serial console. Hold a camera in front of the screen and try to capture the messages as an MP4 movie which can be uploaded to YouTube or something. If the output moves too fast to capture it, artificially slow it down by adding a udelay() to call_console_drivers() in kernel/printk/printk.c. Thanks, Lukas