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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1688CC4332F for ; Tue, 13 Dec 2022 11:37:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=1Kn5F5f8/3RTBFaKE89LUIICAq9tpj1YS/lnAd71gR4=; b=KMi6VwY4F6YWbV 5I4kG1aOqZ8ZNoLNUJAF+eyBxe5vHjvX97MA7hTiy53Cyki5hdgNAZTDgm608ZnZVK/swkIHh4ocY VNpyTtTPMU4biZR5IstzdShWXa6TXw6WSWY9av+lP/Aojw4uWJViWzvnjAicGX/Fqco7VwQFLMlDy TsYFsyCWz90pZyqdO91/KrbtZLcbqVlXaHuG7vkDqCltMVtJMBraJki7X4lDMVPoELxrC8XJ+urQ0 3BiHLIB55NJunoygqD53SNjvDYkEvfI7Kgb+jNR6JnKVxWysQo5VgdTSOiDLMdWRBL5klSSbFE/pK OjuxjXd9qrZHIttu8SIw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p53a4-00GRUw-Cq; Tue, 13 Dec 2022 11:36:16 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1p53a1-00GRRj-08 for linux-arm-kernel@lists.infradead.org; Tue, 13 Dec 2022 11:36:14 +0000 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 89C6A6148B; Tue, 13 Dec 2022 11:36:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3A31EC433D2; Tue, 13 Dec 2022 11:36:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1670931370; bh=EEs6Mg/sfionQP7S0xqd9qRSjYMzb50AzeLFtoibb38=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Y4Uia4vz6ZrDjEJndsHjuxlMYImiRUf2YysatZDeEeJfhcMBwgAnMFDBBHj3GDiGI yPmaELiRVXq9iYDQf/Sfrz7RXKiOzJTMWer7onCopp/XCoLuBbXk6BBStzdn9qAqd5 C5f6tVBXNST0Q/eYq5aJGrOd+x/uDHxtoT2LGbxs+fceIASjTU+XxK0iB+2+RQd3H6 XTSjcK4/L8+P1+rVgLJRA3pyVthAMDOaK2DjZoyHPRTJ/0QJbvPXJNtwPwvIt82yYt Zi56tJa6/+/cAwYC45RtbAeBEvNNWOnMEowSk8stcRwRGXCSVrLBKpDfcf3I1Mwbg1 9Pbcvrluuw4pQ== Date: Tue, 13 Dec 2022 11:36:05 +0000 From: Will Deacon To: Mark Rutland Cc: Steven Rostedt , Ard Biesheuvel , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, samitolvanen@google.com, keescook@chromium.org, mhiramat@kernel.org Subject: Re: [PATCH] ftrace: Allow WITH_ARGS flavour of graph tracer with shadow call stack Message-ID: <20221213113604.GA5719@willie-the-truck> References: <20221209143402.3332369-1-ardb@kernel.org> <20221209165139.37d033ee@gandalf.local.home> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221213_033613_127217_F9723918 X-CRM114-Status: GOOD ( 27.50 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Dec 12, 2022 at 10:36:23AM +0000, Mark Rutland wrote: > On Fri, Dec 09, 2022 at 04:51:39PM -0500, Steven Rostedt wrote: > > On Fri, 9 Dec 2022 14:40:25 +0000 > > Mark Rutland wrote: > > > > > On Fri, Dec 09, 2022 at 03:34:02PM +0100, Ard Biesheuvel wrote: > > > > The recent switch on arm64 from DYNAMIC_FTRACE_WITH_REGS to > > > > DYNAMIC_FTRACE_WITH_ARGS failed to take into account that we currently > > > > require the former in order to allow the function graph tracer to be > > > > enabled in combination with shadow call stacks. This means that this is > > > > no longer permitted at all, in spite of the fact that either flavour of > > > > ftrace works perfectly fine in this combination. > > > > > > > > Given that arm64 is the only arch that implements shadow call stacks in > > > > the first place, let's update the condition to just reflect the arm64 > > > > change. When other architectures adopt shadow call stack support, this > > > > can be revisited if needed. > > > > > > > > Signed-off-by: Ard Biesheuvel > > > > > > My bad; sorry about this, and thanks for the fix! > > > > > > Acked-by: Mark Rutland > > > > > > We should probably also add: > > > > > > Fixes: 26299b3f6ba26bfc ("ftrace: arm64: move from REGS to ARGS") > > > > Actually, I believe it is: > > > > Fixes: ddc9863e9e90 ("scs: Disable when function graph tracing is enabled") > > Ah; it's slightly more subtle since these were on different branches that got > merged. Either's correct in its own branch, and the merge is where things went > wrong. > > I think the overall least confusing thing is to bite the bullet and list both > REGS and ARGS, i.e. > > depends on DYNAMIC_FTRACE_WITH_ARGS || DYNAMIC_FTRACE_WITH_REGS || !FUNCTION_GRAPH_TRACER > > ... and for the fixes tag have: > > Fixes: ddc9863e9e90 ("scs: Disable when function graph tracing is enabled") > > That way the commit is correct regardless of the REGS -> ARGS conversion, and > will work if backported independently. Ard -- please can you respin as per Mark's suggestion above? I can then send it as a fix later this week. Cheers, Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel