pci_find_upstream_pcie_bridge() attempts to return the PCIe-to-PCI bridge upstream from the provided device. It currently returns NULL if 1) the provided device is PCIe (ie. it does not have such an upstream bridge), 2) the device is on the root bus (a subtle case of its claim to return the parent device when not connected to a PCIe bridge), or 3) when it gets lost walking the bus and finds itself on a PCIe device that is not a PCIe-to-PCI bridge. This latter case not only generates a WARN, but treats the provided device the same as if it were PCIe. We can replace 1) and 2) with explicit tests in the IOMMU code as this is the code that knows the visibility of devices at the root bus. That leaves the bus walk case 3), where the NULL return is actually an error. We hit this error because some PCIe-to-PCI bridge vendors ignore the PCIe spec requirement that all PCIe devices must include a PCIe capability, which is all that pci_is_pcie() actually tests. When PCI quirks are enabled, iommu_pci_is_pcie_bridge() adds one more test by looking at the next upstream device to test whether it is PCIe with a type code of a PCIe-to-PCI/PCI-X bridge. If it does not have this type code, then by deduction, the current bridge must be a PCIe-to-PCI bridge and thus be a PCIe bridge. Therefore, pci_find_upstream_pcie_bridge() is replaced by an explicit call to (pci_is_pcie() || pci_is_root_bus()) plus iommu_pci_find_upstream() with the iommu_pci_is_pcie_bridge() match function. This either returns the first PCIe bridge, which must be a PCIe-to-PCI bridge or NULL if not found. In the NULL case, we know the original device is not on the root bus (already tested for that), so we can safely walk from the provided device to the last device and fall into the legacy PCI bridge code. Fixes https://bugzilla.kernel.org/show_bug.cgi?id=44881 Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> --- drivers/iommu/Kconfig | 2 + drivers/iommu/intel-iommu.c | 77 ++++++++++++++++++++++------------- drivers/iommu/intel_irq_remapping.c | 15 +++++-- 3 files changed, 61 insertions(+), 33 deletions(-) diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index a591794..71ec2d5 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -85,6 +85,7 @@ config INTEL_IOMMU depends on PCI_MSI && ACPI && (X86 || IA64_GENERIC) select IOMMU_API select DMAR_TABLE + select IOMMU_PCI help DMA remapping (DMAR) devices support enables independent address translations for Direct Memory Access (DMA) from devices. @@ -125,6 +126,7 @@ config IRQ_REMAP bool "Support for Interrupt Remapping" depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI select DMAR_TABLE + select IOMMU_PCI ---help--- Supports Interrupt remapping for IO-APIC and MSI devices. To use x2apic mode in the CPU's which support x2APIC enhancements or diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index b4f0e28..3748187 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -1689,9 +1689,13 @@ domain_context_mapping(struct dmar_domain *domain, struct pci_dev *pdev, return ret; /* dependent device mapping */ - tmp = pci_find_upstream_pcie_bridge(pdev); - if (!tmp) + if (pci_is_pcie(pdev) || pci_is_root_bus(pdev->bus)) return 0; + + tmp = iommu_pci_find_upstream(pdev, iommu_pci_is_pcie_bridge, &parent); + if (!tmp) + tmp = parent; + /* Secondary interface's bus number and devfn 0 */ parent = pdev->bus->self; while (parent != tmp) { @@ -1703,7 +1707,7 @@ domain_context_mapping(struct dmar_domain *domain, struct pci_dev *pdev, return ret; parent = parent->bus->self; } - if (pci_is_pcie(tmp)) /* this is a PCIe-to-PCI bridge */ + if (iommu_pci_is_pcie_bridge(tmp)) /* this is a PCIe-to-PCI bridge */ return domain_context_mapping_one(domain, pci_domain_nr(tmp->subordinate), tmp->subordinate->number, 0, @@ -1731,9 +1735,13 @@ static int domain_context_mapped(struct pci_dev *pdev) if (!ret) return ret; /* dependent device mapping */ - tmp = pci_find_upstream_pcie_bridge(pdev); + if (pci_is_pcie(pdev) || pci_is_root_bus(pdev->bus)) + return 0; + + tmp = iommu_pci_find_upstream(pdev, iommu_pci_is_pcie_bridge, &parent); if (!tmp) - return ret; + tmp = parent; + /* Secondary interface's bus number and devfn 0 */ parent = pdev->bus->self; while (parent != tmp) { @@ -1743,7 +1751,7 @@ static int domain_context_mapped(struct pci_dev *pdev) return ret; parent = parent->bus->self; } - if (pci_is_pcie(tmp)) + if (iommu_pci_is_pcie_bridge(tmp)) return device_context_mapped(iommu, tmp->subordinate->number, 0); else @@ -1974,7 +1982,7 @@ static struct dmar_domain *get_domain_for_dev(struct pci_dev *pdev, int gaw) struct intel_iommu *iommu; struct dmar_drhd_unit *drhd; struct device_domain_info *info, *tmp; - struct pci_dev *dev_tmp; + struct pci_dev *dev_tmp = NULL; unsigned long flags; int bus = 0, devfn = 0; int segment; @@ -1986,9 +1994,16 @@ static struct dmar_domain *get_domain_for_dev(struct pci_dev *pdev, int gaw) segment = pci_domain_nr(pdev->bus); - dev_tmp = pci_find_upstream_pcie_bridge(pdev); - if (dev_tmp) { - if (pci_is_pcie(dev_tmp)) { + if (!pci_is_pcie(pdev) && !pci_is_root_bus(pdev->bus)) { + struct pci_dev *last; + + dev_tmp = iommu_pci_find_upstream(pdev, + iommu_pci_is_pcie_bridge, + &last); + if (!dev_tmp) + dev_tmp = last; + + if (iommu_pci_is_pcie_bridge(dev_tmp)) { bus = dev_tmp->subordinate->number; devfn = 0; } else { @@ -3754,26 +3769,24 @@ static void iommu_detach_dependent_devices(struct intel_iommu *iommu, { struct pci_dev *tmp, *parent; - if (!iommu || !pdev) + if (!iommu || !pdev || pci_is_pcie(pdev) || pci_is_root_bus(pdev->bus)) return; /* dependent device detach */ - tmp = pci_find_upstream_pcie_bridge(pdev); + tmp = iommu_pci_find_upstream(pdev, iommu_pci_is_pcie_bridge, &parent); + if (!tmp) + tmp = parent; + /* Secondary interface's bus number and devfn 0 */ - if (tmp) { - parent = pdev->bus->self; - while (parent != tmp) { - iommu_detach_dev(iommu, parent->bus->number, - parent->devfn); - parent = parent->bus->self; - } - if (pci_is_pcie(tmp)) /* this is a PCIe-to-PCI bridge */ - iommu_detach_dev(iommu, - tmp->subordinate->number, 0); - else /* this is a legacy PCI bridge */ - iommu_detach_dev(iommu, tmp->bus->number, - tmp->devfn); + parent = pdev->bus->self; + while (parent != tmp) { + iommu_detach_dev(iommu, parent->bus->number, parent->devfn); + parent = parent->bus->self; } + if (iommu_pci_is_pcie_bridge(tmp)) /* this is a PCIe-to-PCI bridge */ + iommu_detach_dev(iommu, tmp->subordinate->number, 0); + else /* this is a legacy PCI bridge */ + iommu_detach_dev(iommu, tmp->bus->number, tmp->devfn); } static void domain_remove_one_dev_info(struct dmar_domain *domain, @@ -4158,7 +4171,7 @@ static int intel_iommu_domain_has_cap(struct iommu_domain *domain, static int intel_iommu_add_device(struct device *dev) { struct pci_dev *pdev = to_pci_dev(dev); - struct pci_dev *bridge, *dma_pdev = NULL; + struct pci_dev *dma_pdev = NULL; struct iommu_group *group; int ret; @@ -4166,9 +4179,15 @@ static int intel_iommu_add_device(struct device *dev) pdev->bus->number, pdev->devfn)) return -ENODEV; - bridge = pci_find_upstream_pcie_bridge(pdev); - if (bridge) { - if (pci_is_pcie(bridge)) + if (!pci_is_pcie(pdev) && !pci_is_root_bus(pdev->bus)) { + struct pci_dev *bridge, *last; + + bridge = iommu_pci_find_upstream(pdev,iommu_pci_is_pcie_bridge, + &last); + if (!bridge) + bridge = last; + + if (iommu_pci_is_pcie_bridge(bridge)) dma_pdev = pci_get_domain_bus_and_slot( pci_domain_nr(pdev->bus), bridge->subordinate->number, 0); diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index 5b19b2d..2a6d27f 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -16,6 +16,7 @@ #include <asm/msidef.h> #include "irq_remapping.h" +#include "pci.h" struct ioapic_scope { struct intel_iommu *iommu; @@ -373,7 +374,6 @@ static int set_hpet_sid(struct irte *irte, u8 id) static int set_msi_sid(struct irte *irte, struct pci_dev *dev) { - struct pci_dev *bridge; if (!irte || !dev) return -1; @@ -385,9 +385,16 @@ static int set_msi_sid(struct irte *irte, struct pci_dev *dev) return 0; } - bridge = pci_find_upstream_pcie_bridge(dev); - if (bridge) { - if (pci_is_pcie(bridge))/* this is a PCIe-to-PCI/PCIX bridge */ + if (!pci_is_pcie(dev) && !pci_is_root_bus(dev->bus)) { + struct pci_dev *bridge, *last; + + bridge = iommu_pci_find_upstream(dev, iommu_pci_is_pcie_bridge, + &last); + if (!bridge) + bridge = last; + + /* PCIe-to-PCI/PCIX bridge */ + if (iommu_pci_is_pcie_bridge(bridge)) set_irte_sid(irte, SVT_VERIFY_BUS, SQ_ALL_16, (bridge->bus->number << 8) | dev->bus->number); else /* this is a legacy PCI bridge */ -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
