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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 82D06C48BE8 for ; Tue, 15 Jun 2021 17:10:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 617506143D for ; Tue, 15 Jun 2021 17:10:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231696AbhFORMS (ORCPT ); Tue, 15 Jun 2021 13:12:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:48172 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231540AbhFORMF (ORCPT ); Tue, 15 Jun 2021 13:12:05 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7DE426143D; Tue, 15 Jun 2021 17:10:00 +0000 (UTC) Date: Tue, 15 Jun 2021 13:09:59 -0400 From: Steven Rostedt To: Rasmus Villemoes Cc: Bartosz Golaszewski , linux-rt-users@vger.kernel.org, LKML , Linus Walleij , Vladimir Oltean , Esben Haabendal Subject: Re: commit 3d5bfbd97163 versus -rt Message-ID: <20210615130959.1de1f52a@gandalf.local.home> In-Reply-To: <37e28373-c6ec-2602-ec5c-cb0b65ce6697@prevas.dk> References: <5afbc89e-dbc4-3f47-4e61-63a77165aaec@prevas.dk> <20210615113312.0dad32bb@oasis.local.home> <37e28373-c6ec-2602-ec5c-cb0b65ce6697@prevas.dk> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 15 Jun 2021 18:24:20 +0200 Rasmus Villemoes wrote: > > ~ # uname -r > > 5.10.42-00001-g10216cf63a12 > > ~ # grep -ow threadirqs /proc/cmdline > > threadirqs > > ~ # zcat /proc/config.gz | grep FORCED_THREADING > > CONFIG_IRQ_FORCED_THREADING=y > > ~ # dmesg | grep WARNING > > ~ # > > And as an extra data point, it also doesn't trigger on 5.10.41-rt42 > configured without PREEMPT_RT but with threadirqs on the command line. Sounds to me that there's a "spin_lock_irq*" somewhere in the path, because from what I can see, there's not much difference with the IRQ code between 5.10.41 and 5.10.41-rt42. But if you are seeing it only with PREEMPT_RT set, that tells me that without PREEMPT_RT, interrupts are disabled at that point, but not with PREEMPT_RT. The only thing I can think of that would do that is a spin_lock_irq*() taken (not a raw_spin_lock_irq*()). -- Steve