From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Previously portdrv allowed the AER service for any device with an AER capability (assuming Linux had control of AER) even though the AER service driver only attaches to Root Port and RCECs. Because get_port_device_capability() included AER for non-RP, non-RCEC devices, we tried to initialize the AER IRQ even though these devices don't generate AER interrupts. Intel DG1 and DG2 discrete graphics cards contain a switch leading to a GPU. The switch supports AER but not MSI, so initializing an AER IRQ failed, and portdrv failed to claim the switch port at all. The GPU itself could be suspended, but the switch could not be put in a low-power state because it had no driver. Don't allow the AER service on non-Root Port, non-Root Complex Event Collector devices. This means we won't enable Bus Mastering if the device doesn't require MSI, the AER service will not appear in sysfs, and the AER service driver will not bind to the device. Link: https://lore.kernel.org/r/20221207084105.84947-1-mika.westerberg@xxxxxxxxxxxxxxx Based-on-patch-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> --- This is a v3 based on Mika's patch at https://lore.kernel.org/r/20221207084105.84947-1-mika.westerberg@xxxxxxxxxxxxxxx I wouldn't normally kibbitz like this, but I'm hoping to squeeze this into the v6.2 merge window. Changes from v2: * Test the device type in get_port_device_capability() instead of pcie_init_service_irqs(). The benefits are to keep the device type checking together (this is similar to the PME test), avoid enabling Bus Mastering unnecessarily, avoid exposing the portdrv AER service in sysfs, and preventing the AER service driver from binding to devices it doesn't need to. drivers/pci/pcie/portdrv.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pcie/portdrv.c b/drivers/pci/pcie/portdrv.c index a6c4225505d5..8b16e96ec15c 100644 --- a/drivers/pci/pcie/portdrv.c +++ b/drivers/pci/pcie/portdrv.c @@ -232,7 +232,9 @@ static int get_port_device_capability(struct pci_dev *dev) } #ifdef CONFIG_PCIEAER - if (dev->aer_cap && pci_aer_available() && + if ((pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT || + pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC) && + dev->aer_cap && pci_aer_available() && (pcie_ports_native || host->native_aer)) services |= PCIE_PORT_SERVICE_AER; #endif -- 2.25.1
