From d8d2b65a940bb497749d66bdab59b530901d3854 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Fri, 9 Dec 2022 11:01:00 -0600 Subject: [PATCH] PCI/portdrv: Allow AER service only for Root Ports & RCECs 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@linux.intel.com Link: https://lore.kernel.org/r/20221210002922.1749403-1-helgaas@kernel.org Based-on-patch-by: Mika Westerberg Signed-off-by: Bjorn Helgaas Reviewed-by: Kuppuswamy Sathyanarayanan --- 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 a6c42255..8b16e96 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 -- 2.7.4