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 01F3FC433EF for ; Wed, 6 Apr 2022 13:12:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231749AbiDFNOk (ORCPT ); Wed, 6 Apr 2022 09:14:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45236 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234113AbiDFNNk (ORCPT ); Wed, 6 Apr 2022 09:13:40 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BFB5824BD4C; Tue, 5 Apr 2022 20:08:17 -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 dfw.source.kernel.org (Postfix) with ESMTPS id C12E86182C; Wed, 6 Apr 2022 03:08:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9887FC385A0; Wed, 6 Apr 2022 03:08:14 +0000 (UTC) Date: Tue, 5 Apr 2022 23:08:12 -0400 From: Steven Rostedt To: Guenter Roeck Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, stable@vger.kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, shuah@kernel.org, patches@kernelci.org, lkft-triage@lists.linaro.org, pavel@denx.de, jonathanh@nvidia.com, f.fainelli@gmail.com, sudipm.mukherjee@gmail.com, slade@sladewatkins.com, Sasha Levin Subject: Re: [PATCH 5.10 000/599] 5.10.110-rc1 review Message-ID: <20220405230812.2feca4ed@gandalf.local.home> In-Reply-To: <20220405225212.061852f9@gandalf.local.home> References: <20220405070258.802373272@linuxfoundation.org> <20220406010749.GA1133386@roeck-us.net> <20220406023025.GA1926389@roeck-us.net> <20220405225212.061852f9@gandalf.local.home> 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, 5 Apr 2022 22:52:12 -0400 Steven Rostedt wrote: > On Tue, 5 Apr 2022 19:30:25 -0700 > Guenter Roeck wrote: > > > > s390 tests crashed. Other failed qemu tests did not compile. > > > > Bisect points to commit 93fe2389e6fd ("tracing: Have TRACE_DEFINE_ENUM > > affect trace event types as well"). Bisect log attached. Reverting the > > offending patch fixes the problem. Copying Steven for comments/input. > > Do you have this commit? > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=795301d3c2899 > OK, I see what happened. I wrote that patch because a new event appeared that used enums in the field format that gets exposed to user space. This patch is only needed for events that do that. Which until this release, nothing did. That patch was then flagged as something to backport (but it was never tagged as stable, so this was one of the "AUTOSEL" backports). And it should have only been backported if any of these new events were also backported. Otherwise, the patch is useless. When this patch was in linux-next, it caused s390 and powerpc to crash. I found the issue and fixed it with the linked patch above, and even added a "Fixes" tag to tie the two commits together. Both of problem patch and the fix went into mainline in the same pull request. Here's a thought, if you decide to backport a patch to stable, and you see that there's another commit with a "Fixes" tag to the automatically selected commit. DO NOT BACKPORT IF THE FIXES PATCH FAILS TO GO BACK TOO! This never should have been backported without the fix. Please revert that patch for any stable release that the fixes patch fails to apply. -- Steve