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, URIBL_BLOCKED,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 33E6AC4727C for ; Fri, 25 Sep 2020 15:30:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9E1320878 for ; Fri, 25 Sep 2020 15:30:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728970AbgIYPax (ORCPT ); Fri, 25 Sep 2020 11:30:53 -0400 Received: from mail.kernel.org ([198.145.29.99]:57664 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727749AbgIYPaw (ORCPT ); Fri, 25 Sep 2020 11:30:52 -0400 Received: from oasis.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 272CF2075F; Fri, 25 Sep 2020 15:30:51 +0000 (UTC) Date: Fri, 25 Sep 2020 11:30:49 -0400 From: Steven Rostedt To: Greg Kroah-Hartman Cc: Naresh Kamboju , Joel Fernandes , Peter Zijlstra , Namhyung Kim , LKML , linux- stable , Sasha Levin , Masami Hiramatsu , LTP List , lkft-triage@lists.linaro.org Subject: Re: [stable 4.19] [PANIC]: tracing: Centralize preemptirq tracepoints and unify their usage Message-ID: <20200925113049.4c10c864@oasis.local.home> In-Reply-To: <20200925151245.GA3180934@kroah.com> References: <20180823023839.GA13343@shao2-debian> <20180828195347.GA228832@joelaf.mtv.corp.google.com> <20200925051518.GA605188@kroah.com> <20200925105458.567d0bf4@oasis.local.home> <20200925105914.7de88d27@oasis.local.home> <20200925110706.6654954b@oasis.local.home> <20200925151245.GA3180934@kroah.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; 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 Fri, 25 Sep 2020 17:12:45 +0200 Greg Kroah-Hartman wrote: > > Specifically, commits: > > > > a0d14b8909de55139b8702fe0c7e80b69763dcfb ("x86/mm, tracing: Fix CR2 corruption") > > 6879298bd0673840cadd1fb36d7225485504ceb4 ("x86/entry/64: Prevent clobbering of saved CR2 value") > > b8f70953c1251d8b16276995816a95639f598e70 ("x86/entry/32: Pass cr2 to do_async_page_fault()") > > > > (which are in 5.4 but not 4.19) > > > > But again, is this too intrusive. There was a workaround that was > > original proposed, but Peter didn't want any more band-aids, and did > > the restructuring, but as you can see from the two other patches, it > > makes it a bit more high risk. > > If those are known to work, why can't I take them as-is? If they apply without tweaks, I say "Go for it" ;-) My worry is that they may have other unknown dependencies. And I only looked at what was applied between 4.19 and 5.4 mainline. I haven't looked at what else may have been backported to fix the above three commits. -- Steve