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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 5CADFCA9ECF for ; Mon, 4 Nov 2019 14:04:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3CD5C218BA for ; Mon, 4 Nov 2019 14:04:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729188AbfKDOEq (ORCPT ); Mon, 4 Nov 2019 09:04:46 -0500 Received: from foss.arm.com ([217.140.110.172]:43744 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727782AbfKDOEp (ORCPT ); Mon, 4 Nov 2019 09:04:45 -0500 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 F30A01FB; Mon, 4 Nov 2019 06:04:44 -0800 (PST) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BA3EA3F6C4; Mon, 4 Nov 2019 06:04:42 -0800 (PST) Date: Mon, 4 Nov 2019 14:04:40 +0000 From: Mark Rutland To: Amit Kachhap Cc: Will Deacon , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Catalin Marinas , "deller@gmx.de" , "duwe@suse.de" , "James.Bottomley@HansenPartnership.com" , James Morse , "jeyu@kernel.org" , "jpoimboe@redhat.com" , "jthierry@redhat.com" , "linux-parisc@vger.kernel.org" , "mingo@redhat.com" , "peterz@infradead.org" , "rostedt@goodmis.org" , "svens@stackframe.org" , "takahiro.akashi@linaro.org" Subject: Re: [PATCHv2 0/8] arm64: ftrace cleanup + FTRACE_WITH_REGS Message-ID: <20191104140440.GJ45140@lakrids.cambridge.arm.com> References: <20191029165832.33606-1-mark.rutland@arm.com> <42c113ee-e7fc-3e94-cca0-f05f1c89fdb8@arm.com> <20191104125637.GB24108@willie-the-truck> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.11.1+11 (2f07cb52) (2018-12-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 04, 2019 at 01:03:51PM +0000, Amit Kachhap wrote: > > > On 11/4/19 6:26 PM, Will Deacon wrote: > > On Sat, Nov 02, 2019 at 05:42:25PM +0530, Amit Daniel Kachhap wrote: > >> On 10/29/19 10:28 PM, Mark Rutland wrote: > >>> This series is a reworked version of Torsten's FTRACE_WITH_REGS series > >>> [1]. I've tried to rework the existing code in preparatory patches so > >>> that the patchable-function-entry bits slot in with fewer surprises. > >>> This version is based on v5.4-rc3, and can be found in my > >>> arm64/ftrace-with-regs branch [2]. > >>> > >>> Patch 1 adds an (optional) ftrace_init_nop(), which the core code uses > >>> to initialize callsites. This allows us to avoid a synthetic MCOUNT_ADDR > >>> symbol, and more cleanly separates the one-time initialization of the > >>> callsite from dynamic NOP<->CALL modification. Architectures which don't > >>> implement this get the existing ftrace_make_nop() with MCOUNT_ADDR. > >>> > >>> Recently parisc gained ftrace support using patchable-function-entry. > >>> Patch 2 makes the handling of module callsite locations common in > >>> kernel/module.c with a new FTRACE_CALLSITE_SECTION definition, and > >>> removed the newly redundant bits from arch/parisc. > >>> > >>> Patches 3 and 4 move the module PLT initialization to module load time, > >>> which simplifies runtime callsite modification. This also means that we > >>> don't transitently mark the module text RW, and will allow for the > >>> removal of module_disable_ro(). > >>> > >>> Patches 5 and 6 add some trivial infrastructure, with patch 7 finally > >>> adding FTRACE_WITH_REGS support. Additional work will be required for > >>> livepatching (e.g. implementing reliable stack trace), which is > >>> commented as part of patch 7. > >>> > >>> Patch 8 is a trivial cleanup atop of the rest of the series, making the > >>> code easier to read and less susceptible to config-specific breakage. > >> I tested the whole series with my latest in-kernel ptrauth patches [1] > >> and graph_tracer/function_graph_tracer works fine, So for the whole series, > >> Tested-by: Amit Daniel Kachhap > >> > >> Also I gave few minor comments in the individual patches. With those > >> comments, > >> Signed-off-by: Amit Daniel Kachhap > Oops sorry I meant, > Reviewed-off-by: Amit Daniel Kachhap Thanks! I've added the Tested-by for the whole series, and the Reviewed-by for patches 4 and 7. I haven't added it for patch 1 just yet; please reply to my comment there if you'd still like to add a Reviewed-by. Mark.