| Message ID | 20150420233055.20866.87460.stgit@bhelgaas-glaptop2.roam.corp.google.com |
|---|---|
| State | Accepted |
| Headers | show |
On Monday, April 20, 2015 06:30:55 PM Bjorn Helgaas wrote: > Prior to c770cb4cb505 ("PCI: Mark invalid BARs as unassigned"), if we tried > to claim a PCI BAR but could not find an upstream bridge window that > matched it, we complained but still allowed the device to be enabled. > > c770cb4cb505 broke devices that previously worked (mptsas and igb in the > case Tony reported, but it could be any devices) because it marks those > BARs as IORESOURCE_UNSET, which makes pci_enable_device() complain and > return failure: > > igb 0000:81:00.0: can't enable device: BAR 0 [mem size 0x00020000] not assigned > igb: probe of 0000:81:00.0 failed with error -22 > > The underlying cause is an ACPI Address Space Descriptor for a PCI host > bridge window that is marked as "consumer". This is a firmware defect: > resources that are produced on the downstream side of a bridge should be > marked "producer". But rejecting these BARs that we previously allowed is > a functionality regression, and firmware has not used the producer/consumer > bit consistently, so we can't rely on it anyway. > > Stop checking the producer/consumer bit, and assume all bridge Address > Space Descriptors are for bridge windows. > > Note that this change does not affect I/O Port or Fixed Location I/O Port > Descriptors, which are commonly used for the [io 0x0cf8-0x0cff] config > access range. That range is a "consumer" range and should not be treated > as a window. > > Fixes: c770cb4cb505 ("PCI: Mark invalid BARs as unassigned") > Link: https://bugzilla.kernel.org/show_bug.cgi?id=96961 > Reported-and-tested-by: Tony Luck <tony.luck@intel.com> > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Apr 20, 2015 at 6:30 PM, Bjorn Helgaas <bhelgaas@google.com> wrote: > Prior to c770cb4cb505 ("PCI: Mark invalid BARs as unassigned"), if we tried > to claim a PCI BAR but could not find an upstream bridge window that > matched it, we complained but still allowed the device to be enabled. > > c770cb4cb505 broke devices that previously worked (mptsas and igb in the > case Tony reported, but it could be any devices) because it marks those > BARs as IORESOURCE_UNSET, which makes pci_enable_device() complain and > return failure: > > igb 0000:81:00.0: can't enable device: BAR 0 [mem size 0x00020000] not assigned > igb: probe of 0000:81:00.0 failed with error -22 > > The underlying cause is an ACPI Address Space Descriptor for a PCI host > bridge window that is marked as "consumer". This is a firmware defect: > resources that are produced on the downstream side of a bridge should be > marked "producer". But rejecting these BARs that we previously allowed is > a functionality regression, and firmware has not used the producer/consumer > bit consistently, so we can't rely on it anyway. > > Stop checking the producer/consumer bit, and assume all bridge Address > Space Descriptors are for bridge windows. > > Note that this change does not affect I/O Port or Fixed Location I/O Port > Descriptors, which are commonly used for the [io 0x0cf8-0x0cff] config > access range. That range is a "consumer" range and should not be treated > as a window. > > Fixes: c770cb4cb505 ("PCI: Mark invalid BARs as unassigned") > Link: https://bugzilla.kernel.org/show_bug.cgi?id=96961 > Reported-and-tested-by: Tony Luck <tony.luck@intel.com> > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> I applied this with Rafael's ack to for-linus for v4.1-rc1. > --- > arch/ia64/pci/pci.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c > index 48cc65705db4..d4e162d35b34 100644 > --- a/arch/ia64/pci/pci.c > +++ b/arch/ia64/pci/pci.c > @@ -240,15 +240,12 @@ static acpi_status resource_to_window(struct acpi_resource *resource, > * We're only interested in _CRS descriptors that are > * - address space descriptors for memory or I/O space > * - non-zero size > - * - producers, i.e., the address space is routed downstream, > - * not consumed by the bridge itself > */ > status = acpi_resource_to_address64(resource, addr); > if (ACPI_SUCCESS(status) && > (addr->resource_type == ACPI_MEMORY_RANGE || > addr->resource_type == ACPI_IO_RANGE) && > - addr->address.address_length && > - addr->producer_consumer == ACPI_PRODUCER) > + addr->address.address_length) > return AE_OK; > > return AE_ERROR; > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c index 48cc65705db4..d4e162d35b34 100644 --- a/arch/ia64/pci/pci.c +++ b/arch/ia64/pci/pci.c @@ -240,15 +240,12 @@ static acpi_status resource_to_window(struct acpi_resource *resource, * We're only interested in _CRS descriptors that are * - address space descriptors for memory or I/O space * - non-zero size - * - producers, i.e., the address space is routed downstream, - * not consumed by the bridge itself */ status = acpi_resource_to_address64(resource, addr); if (ACPI_SUCCESS(status) && (addr->resource_type == ACPI_MEMORY_RANGE || addr->resource_type == ACPI_IO_RANGE) && - addr->address.address_length && - addr->producer_consumer == ACPI_PRODUCER) + addr->address.address_length) return AE_OK; return AE_ERROR;
Prior to c770cb4cb505 ("PCI: Mark invalid BARs as unassigned"), if we tried to claim a PCI BAR but could not find an upstream bridge window that matched it, we complained but still allowed the device to be enabled. c770cb4cb505 broke devices that previously worked (mptsas and igb in the case Tony reported, but it could be any devices) because it marks those BARs as IORESOURCE_UNSET, which makes pci_enable_device() complain and return failure: igb 0000:81:00.0: can't enable device: BAR 0 [mem size 0x00020000] not assigned igb: probe of 0000:81:00.0 failed with error -22 The underlying cause is an ACPI Address Space Descriptor for a PCI host bridge window that is marked as "consumer". This is a firmware defect: resources that are produced on the downstream side of a bridge should be marked "producer". But rejecting these BARs that we previously allowed is a functionality regression, and firmware has not used the producer/consumer bit consistently, so we can't rely on it anyway. Stop checking the producer/consumer bit, and assume all bridge Address Space Descriptors are for bridge windows. Note that this change does not affect I/O Port or Fixed Location I/O Port Descriptors, which are commonly used for the [io 0x0cf8-0x0cff] config access range. That range is a "consumer" range and should not be treated as a window. Fixes: c770cb4cb505 ("PCI: Mark invalid BARs as unassigned") Link: https://bugzilla.kernel.org/show_bug.cgi?id=96961 Reported-and-tested-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> --- arch/ia64/pci/pci.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html