From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 233BE311C35 for ; Thu, 27 Nov 2025 09:29:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764235787; cv=none; b=TDxpXxAnh/U4hJNg9pGhfy68p7OsR6q24MgTIqRQfBJOzJv8Rn9XR4RPEh3v77B/lpDxIMIOCPTO2zJZhirGNpdk7wp14BQH8kKN1oZKza7Ax+T29QTmNM9M+hEODwOEmrh8coDFcdlEGd7Jnd3Crkn0eJeXmRmMDbp2ccDAXtE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764235787; c=relaxed/simple; bh=K8DmXvA+TB2vU/31Wm/gH6QuVM0JfP25Oyqi2FtPu4U=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=St6K4A3hbVaqcr2pXDN/pjrGL7ilho8YzEDYPVoGNPvJTU82rxuGwH9h+a37KZAr2DspX9QwkAm/F6mL7giN5BxESpacevqPSySSkS+W216gxkeHlhIcUaRPgTDSqYH+m+MUa4YY0yVExC4HRHdjbl2/XhM+D+36bM4SE0kg7pw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 0A0FA1477; Thu, 27 Nov 2025 01:29:37 -0800 (PST) Received: from localhost (e132581.arm.com [10.1.196.87]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 14F563F66E; Thu, 27 Nov 2025 01:29:43 -0800 (PST) Date: Thu, 27 Nov 2025 09:29:42 +0000 From: Leo Yan To: Mike Leach Cc: James Clark , Kuan-Wei Chiu , suzuki.poulose@arm.com, alexander.shishkin@linux.intel.com, pratikp@codeaurora.org, mathieu.poirier@linaro.org, gregkh@linuxfoundation.org, jserv@ccns.ncku.edu.tw, marscheng@google.com, ericchancf@google.com, milesjiang@google.com, nickpan@google.com, coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] coresight: etm3x: Fix buffer overwrite in cntr_val_show() Message-ID: <20251127092942.GO724103@e132581.arm.com> References: <20251121002350.1166758-1-visitorckw@gmail.com> <20251126120914.GH724103@e132581.arm.com> <20251126123147.GI724103@e132581.arm.com> <15d536f2-0829-4f3f-b111-b15b14236bd2@linaro.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Nov 26, 2025 at 04:14:19PM +0000, Mike Leach wrote: [...] > > > The key to this is not the questions we are asked, but which platforms > > > are still supported by the linux kernel. > > > > > > The ETMv3 driver supports both ETMv3 and PTM trace (the programming > > > model is the same, even if the trace decode is vastly different). > > > > > > So as long as there are platforms supported that use either of those, > > > we need to keep the driver in. > > > > > > > We're not running tests though, so if we find out it's fundamentally > > broken somehow it could be another justification to remove it, even if > > the kernel supports the devices. Do you have a board that you can test > > on Mike? > > Don't have one myself, but I believe the TC2 was used in development, > (that's the A15/A7 32 bit part - not total compute!) which somewhat > conveniently had both etmv3 and ptm trace. If ETMv4 can be used by Armv7 (arm32) CPUs, and nowdays if Armv7 + ETMv4 is a popular design, it makes sense for me to remove ETMv3 driver. If Armv7 CPUs are always bound to ETMv3 / PTM, then we should keep the driver. Thanks, Leo