Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754028AbbLDA2H (ORCPT ); Thu, 3 Dec 2015 19:28:07 -0500 Received: from mail.kernel.org ([198.145.29.136]:35665 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753654AbbLDA2D (ORCPT ); Thu, 3 Dec 2015 19:28:03 -0500 Date: Thu, 3 Dec 2015 18:27:59 -0600 From: Bjorn Helgaas To: Phil Edworthy Cc: Thomas Gleixner , Jiang Liu , Bjorn Helgaas , "linux-kernel@vger.kernel.org" , Wolfram Sang , "linux-pci@vger.kernel.org" Subject: Re: [PATCH] PCI: MSI: Only use the generic MSI layer when domain is hierarchical Message-ID: <20151204002758.GA10479@localhost> References: <1448288826-19058-1-git-send-email-marc.zyngier@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2526 Lines: 66 On Mon, Nov 30, 2015 at 10:25:34AM +0000, Phil Edworthy wrote: > Cc'd linux-pci ml > > On 23 November 2015 14:27, Marc Zyngier wrote: > > Since d8a1cb757550 ("PCI/MSI: Let pci_msi_get_domain use struct > device::msi_domain"), we use the MSI domain associated to the PCI device. > > But finding a MSI domain doesn't mean that the domain is implemented > using the generic MSI domain API, and a number of MSI controllers > are still using the arch_setup_msi_irq/arch_teardown_msi_irqs. > > In order to avoid a firework on these systems, check that the domain > we just obtained is hierarchical. If not, don't use the generic MSI > stuff and stick with the old one. Not pretty, but reliable. > > Another insentive to rework those drivers and phase out this API. > > Reported-by: Phil Edworthy > Tested-by: Phil Edworthy > Signed-off-by: Marc Zyngier Thanks, I applied this with Thomas' ack to pci/msi for v4.5. It looks like d8a1cb757550 appeared in v4.3. Is this a fix for that commit? Does this need to be backported via a stable tag? > --- > drivers/pci/msi.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c > index 53e4632..7eaa4c8 100644 > --- a/drivers/pci/msi.c > +++ b/drivers/pci/msi.c > @@ -54,7 +54,7 @@ static int pci_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) > struct irq_domain *domain; > > domain = pci_msi_get_domain(dev); > - if (domain) > + if (domain && irq_domain_is_hierarchy(domain)) > return pci_msi_domain_alloc_irqs(domain, dev, nvec, type); > > return arch_setup_msi_irqs(dev, nvec, type); > @@ -65,7 +65,7 @@ static void pci_msi_teardown_msi_irqs(struct pci_dev *dev) > struct irq_domain *domain; > > domain = pci_msi_get_domain(dev); > - if (domain) > + if (domain && irq_domain_is_hierarchy(domain)) > pci_msi_domain_free_irqs(domain, dev); > else > arch_teardown_msi_irqs(dev); > -- > 2.1.4 > > -- > 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/ -- 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/