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 15602C77B6C for ; Sat, 8 Apr 2023 14:05:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229989AbjDHOFF (ORCPT ); Sat, 8 Apr 2023 10:05:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38234 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229988AbjDHOFC (ORCPT ); Sat, 8 Apr 2023 10:05:02 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2A8601026B for ; Sat, 8 Apr 2023 07:04:35 -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 1CC36609FF for ; Sat, 8 Apr 2023 14:03:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1FB09C433D2; Sat, 8 Apr 2023 14:03:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1680962629; bh=mHNb6f80yV6HAqlcDpofJ/tN8EubMjP7pWEZDrzIG3o=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=puPebhxdOUMmy5BqO08AOWiOeqXlX7Pcb1ehTkaLEi594ZcPdzBnbM3wWmnP7GR8x Othlp8nbXAiEuaXMfXok4BaOFVVMdXXgtxfSDU8du1Y6Xty+kBhyaXXg4Gn0+n3SgW 08l1qCH9GpmO2OAwfXVBbglz2mxJkD9lBlavPvoHj/sZFdngl53Z4O0eBNIuR9s8BG 1NgXqTk1lsUHIUaI8rpz3J8FYXeHPN+7kVa8wYuIpKr3vYgvWW4H4n87uN8x9qxu4C ifml6RRXOtLL6mmUOoeXn30OsPIQL0z6kgCtmSt1MbNTJAPZJcJdcD7VpUGRNbrwkg 6MaBfjvfykDvg== Date: Sat, 8 Apr 2023 23:03:44 +0900 From: Masami Hiramatsu (Google) To: Steven Rostedt Cc: Mark Rutland , Mathieu Desnoyers , linux-kernel@vger.kernel.org, Masami Hiramatsu , "Jose E . Marchesi" , Nick Desaulniers , Sami Tolvanen , Peter Zijlstra Subject: Re: [PATCH v3] tracepoint: Fix CFI failures with tp_sub_func Message-Id: <20230408230344.06f9c6c95d4659b2f5363ba0@kernel.org> In-Reply-To: <20230404162232.1b2f4c2f@gandalf.local.home> References: <20230324123142.7463-1-mathieu.desnoyers@efficios.com> <75dbeff6-fd0c-aec1-5821-919088eda6c4@efficios.com> <20230404162232.1b2f4c2f@gandalf.local.home> X-Mailer: Sylpheed 3.7.0 (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 Tue, 4 Apr 2023 16:22:41 -0400 Steven Rostedt wrote: > On Tue, 4 Apr 2023 11:59:26 +0100 > Mark Rutland wrote: > > > Sorry to ping, but are you planning to pick this up, and/or did you want this > > resent with the Testing-by typo fixed? > > > > I couldn't spot it in the tracing tree, and I'm not sure if it's still on your > > TODO list for review or has just been missed. > > Actually, we may be going back to your original patches, as having a stub > function for every trace event will allow us to attach fprobes to them. And > we actually have a need to do that (connecting to tracepoints to get more > info than the trace event gives). > > Masami is currently working on this. I think we need another stub function similar to the original patch, because the __tracestub_* functions are usually not called back. Even if I enabled the static key to enable the stub callback, if user sets another callback handler to the tracepoint (e.g. enable trace event on it), the __tracestub_* function is not called anymore. Thus I think we just pick this version and add another patch to introduce __probestub_* functions in macro, and fprobe on it. This new stub function is something like the original one so that it doesn't break CFI. And it will be registered to tracepoint when the new fprobe based dynamic event is enabled. Thank you, -- Masami Hiramatsu (Google)