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 A6DDCC433EF for ; Sun, 26 Jun 2022 09:18:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234165AbiFZJSw (ORCPT ); Sun, 26 Jun 2022 05:18:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234151AbiFZJSv (ORCPT ); Sun, 26 Jun 2022 05:18:51 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 4E538F5B9; Sun, 26 Jun 2022 02:18:50 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 47C0A2B; Sun, 26 Jun 2022 02:18:50 -0700 (PDT) Received: from FVFF77S0Q05N (unknown [10.57.71.61]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0447E3F792; Sun, 26 Jun 2022 02:18:47 -0700 (PDT) Date: Sun, 26 Jun 2022 10:18:44 +0100 From: Mark Rutland To: "Madhavan T. Venkataraman" Cc: Will Deacon , broonie@kernel.org, jpoimboe@redhat.com, ardb@kernel.org, nobuta.keiya@fujitsu.com, sjitindarsingh@gmail.com, catalin.marinas@arm.com, jamorris@linux.microsoft.com, linux-arm-kernel@lists.infradead.org, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, maz@kernel.org, Kalesh Singh Subject: Re: [PATCH v15 0/6] arm64: Reorganize the unwinder and implement stack trace reliability checks Message-ID: References: <20220617210717.27126-1-madvenka@linux.microsoft.com> <20220623173224.GB16966@willie-the-truck> <66545c21-cfcf-60eb-4acf-39be99520369@linux.microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <66545c21-cfcf-60eb-4acf-39be99520369@linux.microsoft.com> Precedence: bulk List-ID: X-Mailing-List: live-patching@vger.kernel.org On Fri, Jun 24, 2022 at 12:19:01AM -0500, Madhavan T. Venkataraman wrote: > > > On 6/23/22 12:32, Will Deacon wrote: > > On Fri, Jun 17, 2022 at 04:07:11PM -0500, madvenka@linux.microsoft.com wrote: > >> From: "Madhavan T. Venkataraman" > >> > >> I have synced this patch series to v5.19-rc2. > >> I have also removed the following patch. > >> > >> [PATCH v14 7/7] arm64: Select HAVE_RELIABLE_STACKTRACE > >> > >> as HAVE_RELIABLE_STACKTRACE depends on STACK_VALIDATION which is not present > >> yet. This patch will be added in the future once Objtool is enhanced to > >> provide stack validation in some form. > > > > Given that it's not at all obvious that we're going to end up using objtool > > for arm64, does this patch series gain us anything in isolation? > > > > BTW, I have synced my patchset to 5.19-rc2 and sent it as v15. > > So, to answer your question, patches 1 thru 3 in v15 are still useful even if we don't > consider reliable stacktrace. These patches reorganize the unwinder code based on > comments from both Mark Rutland and Mark Brown. Mark Brown has already OKed them. > If Mark Rutland OKes them, we should upstream them. Sorry for the delay; I have been rather swamped recently and haven't had the time to give this the time it needs. I'm happy with patches 1 and 2, and I've acked those in case Will wants to pick them. Kalesh (cc'd) is working to share the unwinder code with hyp, and I think that we need to take a step back and consider how we can make the design work cleanly with that. I'd had a go at prototyping making the unwinder more data driven, but I haven't come up with something satisfactory so far. It would be good if you could look at / comment on each others series. Thanks, Mark. > > I can drop patches 4 thru 6. Actually, the objtool patch series that I have > sent separately for supporting livepatch already addresses reliability. So, if that > gets reviewed and accepted, we don't even need patches 4 thru 6. > > If you are OK with that, I can resend v16 with just patches 1 thru 3. Let me know. > > Madhavan >