Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757692AbaKUBW7 (ORCPT ); Thu, 20 Nov 2014 20:22:59 -0500 Received: from szxga01-in.huawei.com ([119.145.14.64]:41078 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756956AbaKUBW6 (ORCPT ); Thu, 20 Nov 2014 20:22:58 -0500 Message-ID: <546E93DC.8010902@huawei.com> Date: Fri, 21 Nov 2014 09:22:36 +0800 From: Yijing Wang User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.0.1 MIME-Version: 1.0 To: Marc Zyngier , Bjorn Helgaas CC: Thomas Gleixner , "linux-arm-kernel@lists.infradead.org" , , "linux-kernel@vger.kernel.org" , Jiang Liu , Will Deacon , "Catalin Marinas" Subject: Re: Removal of bus->msi assignment breaks MSI with stacked domains References: <546E1771.4030201@arm.com> In-Reply-To: <546E1771.4030201@arm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.27.212] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014/11/21 0:31, Marc Zyngier wrote: > Bjorn, Yijing, > > I've just realized that patch c167caf8d174 (PCI/MSI: Remove useless > bus->msi assignment) completely breaks MSI on arm64 when using the new > MSI stacked domain: Sorry, this is my first part to refactor MSI related code, now how to get pci msi_controller depends arch functions(pcibios_msi_controller() or arch_setup_msi_irq()), we are working on generic pci_host_bridge, after that, we could eventually eliminate MSI arch functions and find pci dev 's msi controller by pci_host_bridge->get_msi_controller(). Marc, could you tell me what pci host driver in your test platform ? > > This patch relies on architectures to implement either > pcibios_msi_controller() or arch_setup_msi_irq(). It turns out that with > stacked domains, none of this is actually necessary, as long as you can > access to the msi_controller. > > And everything was fine until this patch came around (and managed to > test on a system where the PCI devices are not directly attached to the > root bus). Of course, everything now breaks, as we cannot get to the MSI > controller (which contains the domain we allocate the MSIs from). > > In short, this patch breaks an important feature on which arm64 relies, > and I believe this patch should be reverted ASAP. Bjorn, could you help to revert this patch ? > > Thanks, > > M. > -- Thanks! Yijing -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/