From 3845d2953aacf00ad069806ba8d1495675069f23 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 4 Dec 2015 10:28:14 -0600 Subject: [PATCH] PCI/MSI: Only use the generic MSI layer when domain is hierarchical Since d8a1cb757550 ("PCI/MSI: Let pci_msi_get_domain use struct device::msi_domain"), we use the MSI domain associated with the PCI device. But finding an 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 arch_setup_msi_irq() and arch_teardown_msi_irqs(). Check that the domain we just obtained is hierarchical. If it is, we can use the new generic MSI stuff. Otherwise we have to fall back to the old arch_setup_msi_irq() and arch_teardown_msi_irqs() interfaces. This avoids an oops in msi_domain_alloc_irqs() on systems with R-Car, Tegra, Armada 370, and probably other DesignWare-based host controllers. Fixes: d8a1cb757550 ("PCI/MSI: Let pci_msi_get_domain use struct device::msi_domain") Reported-by: Phil Edworthy Tested-by: Phil Edworthy Signed-off-by: Marc Zyngier Signed-off-by: Bjorn Helgaas Acked-by: Thomas Gleixner CC: stable@vger.kernel.org # v4.3+ --- 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); -- 2.7.4