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 DE1D8C54F54 for ; Fri, 31 Jul 2026 16:32:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=3oSPo/QkAHOUHrcuIVZ6KwocCD4v1uwf/1m4LU9tfeE=; b=RBrrPlKA/l/81QCVORKG0I3fjc dEPZmNPbmfQrJD6IlOhu6MW0SUCJJD0I2U5Z0Jhw8dzrzoemX2w0LwPr+MDYZ6djCWBd5QfTgIiyM ED9oK09Lb22hZ/YiK1KmSb0Iaj1jsQaHWV44pHb5sFNBPqQ/OpKZ0QUzTGpT8Yd0xRcPSCMohrla/ paQKtRdcXtOlSJDJfZVcl+Tee5kt5ibDvSCdWhI1OGtyxPh37f82w6j9YdEMC6ySkr52S2F+f8FGZ 65X1V6jIwR3RbN+9frIAwCLDVEduq8fIjHlgHC+TUlKHyBRnYhWmdvD1X+BWLJyuHuVh4C/H4ZNEL RmhEZ4OQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wpq9j-0000000D8oY-1dcT; Fri, 31 Jul 2026 16:32:19 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wpq9h-0000000D8nU-0ik1 for linux-arm-kernel@lists.infradead.org; Fri, 31 Jul 2026 16:32:18 +0000 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 2E4B1204C; Fri, 31 Jul 2026 09:32:12 -0700 (PDT) Received: from [192.168.178.24] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 71A233F86F; Fri, 31 Jul 2026 09:32:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1785515536; bh=VbxlaKfrlvVQz4HJBJtoAZXt2oWQTXMKrfRAQCHlrvA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=hPN34vbp4F+JtFjYjq6NM52DmQeW5hEDr6P+aePDLP9XQTBQlk/4DQFEiSoKV7i9C 9tODQZM7wZhedQAcGCLw4TeprZtegBAK6FHBJmda9baR/SbeWQElXQPVb/B+u6elaV RDBrh+ctknoQg4I+hoR4xBAtYGanTZKVFUFlZhpc= Message-ID: <771b0fb7-7689-49dd-a06f-8bef174e432d@arm.com> Date: Fri, 31 Jul 2026 18:32:06 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 00/10] arm_mpam: Add MPAM-Fb firmware support To: Ben Horgan , Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Catalin Marinas , Will Deacon , "Rafael J . Wysocki" , Len Brown , James Morse , Reinette Chatre , Fenghua Yu Cc: Jonathan Cameron , Srivathsa L Rao , Ganapatrao Kulkarni , Trilok Soni , Srinivas Ramana , Niyas Sait , Lee Trager , Ritwick Sharma , linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20260730152539.2712312-1-andre.przywara@arm.com> Content-Language: en-GB From: Andre Przywara In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260731_093217_328766_A694B981 X-CRM114-Status: GOOD ( 16.85 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Ben, On 7/30/26 19:10, Ben Horgan wrote: > Hi Andre, > > On 7/30/26 16:25, Andre Przywara wrote: > [...] >> The first six patches rework all MSC access wrappers to propagate error >> information. Pure MMIO based MSC accesses would never fail, but the >> MPAM-Fb access can go wrong in multiple ways. The patches have been split >> up purely for reviewing reasons, if the number is a problem, we could as >> well squash them. Please note that until the very last patch of this series >> any MSC accesses would always only return 0, it's only the final enablement >> of MPAM-Fb that could possibly introduce errors. Hence all former patches >> can add error handling gradually, those code paths wouldn't be triggered >> before patch 10/10. > > I had a go at injecting some errors and noticed that at least some aren't getting to user space. > When writing the schemata file any MPAM-Fb error is not propagated to the user. The > resctrl_arch_update_domains() continues to return 0 as there are some missing links in the chain > down to the writes, e.g. __write_config() always returns 0. Ah yeah, that's true. With the write functions using a compatible prototype (just ignoring the new return value) this is harder to check, since the compiler is just fine with it. So I propagate all MSC access errors now in mpam_reprogram_ris_partid(), and the depending mpam_apply_config(), __write_config and mpam_reset_ris() functions. From my quick analysis I'd say that covers all functions now that mpam_devices.c exports. That will be a new patch 07/11. Cheers, Andre