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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 C23D5C433E1 for ; Tue, 11 Aug 2020 18:46:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9DBA7206B2 for ; Tue, 11 Aug 2020 18:46:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726469AbgHKSqP (ORCPT ); Tue, 11 Aug 2020 14:46:15 -0400 Received: from mga04.intel.com ([192.55.52.120]:5951 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725886AbgHKSqP (ORCPT ); Tue, 11 Aug 2020 14:46:15 -0400 IronPort-SDR: LSPeF3B+LX4vl1lWNcYbpxjiqfmUgbs8wZ3K+hnR5DBfFwT8i0THNRsVvdfyKuZ7cTnccptevQ i0BGJ/a6AXXQ== X-IronPort-AV: E=McAfee;i="6000,8403,9710"; a="151236838" X-IronPort-AV: E=Sophos;i="5.76,301,1592895600"; d="scan'208";a="151236838" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Aug 2020 11:46:13 -0700 IronPort-SDR: 5aAcR8S72zxamrk1GkqcpkTcLHD6X+V0Qd8VhcPMwxe6NQm/ajJO1T7QBs6tN6/S8h9BEKMK9n htpZpANtoRxw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.76,301,1592895600"; d="scan'208";a="294806955" Received: from orsmsx602-2.jf.intel.com (HELO ORSMSX602.amr.corp.intel.com) ([10.22.229.82]) by orsmga006.jf.intel.com with ESMTP; 11 Aug 2020 11:46:13 -0700 Received: from orsmsx602.amr.corp.intel.com (10.22.229.15) by ORSMSX602.amr.corp.intel.com (10.22.229.15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Tue, 11 Aug 2020 11:46:13 -0700 Received: from orsmsx101.amr.corp.intel.com (10.22.225.128) by orsmsx602.amr.corp.intel.com (10.22.229.15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.1713.5 via Frontend Transport; Tue, 11 Aug 2020 11:46:13 -0700 Received: from [10.212.86.9] (10.212.86.9) by ORSMSX101.amr.corp.intel.com (10.22.225.128) with Microsoft SMTP Server (TLS) id 14.3.439.0; Tue, 11 Aug 2020 11:46:12 -0700 Subject: Re: [PATCH RFC v2 02/18] irq/dev-msi: Add support for a new DEV_MSI irq domain To: Thomas Gleixner , Jason Gunthorpe , "gregkh@linuxfoundation.org" CC: Marc Zyngier , "Jiang, Dave" , "vkoul@kernel.org" , "bhelgaas@google.com" , "rafael@kernel.org" , "hpa@zytor.com" , "alex.williamson@redhat.com" , "Pan, Jacob jun" , "Raj, Ashok" , "Liu, Yi L" , "Lu, Baolu" , "Tian, Kevin" , "Kumar, Sanjay K" , "Luck, Tony" , "Lin, Jing" , "Williams, Dan J" , "kwankhede@nvidia.com" , "eric.auger@redhat.com" , "parav@mellanox.com" , "Hansen, Dave" , "netanelg@mellanox.com" , "shahafs@mellanox.com" , "yan.y.zhao@linux.intel.com" , "pbonzini@redhat.com" , "Ortiz, Samuel" , "Hossain, Mona" , "dmaengine@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , "linux-pci@vger.kernel.org" , "kvm@vger.kernel.org" , , Boris Ostrovsky , Juergen Gross References: <87h7tcgbs2.fsf@nanos.tec.linutronix.de> <87ft8uxjga.fsf@nanos> <87d03x5x0k.fsf@nanos.tec.linutronix.de> From: "Dey, Megha" Message-ID: <8a8a853c-cbe6-b19c-f6ba-c8cdeda84a36@intel.com> Date: Tue, 11 Aug 2020 11:46:10 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <87d03x5x0k.fsf@nanos.tec.linutronix.de> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [10.212.86.9] Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Thomas, On 8/11/2020 2:53 AM, Thomas Gleixner wrote: > Thomas Gleixner writes: > > CC+: XEN folks > >> Thomas Gleixner writes: >>> The infrastructure itself is not more than a thin wrapper around the >>> existing msi domain infrastructure and might even share code with >>> platform-msi. >> And the annoying fact that you need XEN support which opens another can >> of worms... hmm I am not sure why we need Xen support... are you referring to idxd using xen? > which needs some real cleanup first. > > x86 still does not associate the irq domain to devices at device > discovery time, i.e. the device::msi_domain pointer is never populated. > > So to support this new fangled device MSI stuff we'd need yet more > x86/xen specific arch_*msi_irqs() indirection and hackery, which is not > going to happen. > > The right thing to do is to convert XEN MSI support over to proper irq > domains. This allows to populate device::msi_domain which makes a lot of > things simpler and also more consistent. do you think this cleanup is to be a precursor to my patches? I could look into it but I am not familiar with the background of Xen and this stuff. Can you please provide further guidance on where to look? > Thanks, > > tglx