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 B2985C433FE for ; Wed, 2 Nov 2022 16:04:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231229AbiKBQEh (ORCPT ); Wed, 2 Nov 2022 12:04:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43896 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231163AbiKBQEU (ORCPT ); Wed, 2 Nov 2022 12:04:20 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11B222CE30 for ; Wed, 2 Nov 2022 09:03:42 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 83527B82386 for ; Wed, 2 Nov 2022 16:03:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 197AAC433D6; Wed, 2 Nov 2022 16:03:40 +0000 (UTC) Date: Wed, 2 Nov 2022 12:03:38 -0400 From: Steven Rostedt To: postix@posteo.eu Cc: 20221031144850.5522b036@rorschach.local.home, linux-kernel@vger.kernel.org, regressions@lists.linux.dev, tiwai@suse.de Subject: Re: [REGRESSION 6.0.x / 6.1.x] NULL dereferencing at tracing Message-ID: <20221102120338.254741f7@rorschach.local.home> In-Reply-To: <25d7e982-f959-d86c-a6e7-5efd1db1e75c@posteo.de> References: <71829e56-a13f-0462-37a7-a4d64c16f561@posteo.de> <25d7e982-f959-d86c-a6e7-5efd1db1e75c@posteo.de> 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 Wed, 2 Nov 2022 15:57:56 +0000 postix@posteo.eu wrote: > Hello everyone, > > I have added lot's of debug printk's to see what's happening and I found > that the "cpu" counter, which is used to access the buffer's array > elements (cpu_buffer = buffer->buffers[cpu]) in the ring_buffer_wake_waiters > function, exceeds the maximum number of total of total cores, namely in > my case 24, which means, it should only run from 0..23. However, upon > debugging, it runs up to 31, and thus causing a NULL pointer dereference > (&cpu_buffer->irq_work). > Could you add this patch. https://lore.kernel.org/all/20221101191009.1e7378c8@rorschach.local.home/ Thanks, -- Steve