From: Alex Williamson alex.williamson@redhat.com
commit 2d2f4273cbe9058d1f5a518e5e880d27d7b3b30f upstream.
Commit 0e7df22401a3 ("PCI: Add sysfs sriov_drivers_autoprobe to control VF driver binding") introduced the sriov_drivers_autoprobe attribute which allows users to prevent the kernel from automatically probing a driver for new VFs as they are created. This allows VFs to be spawned without automatically binding the new device to a host driver, such as in cases where the user intends to use the device only with a meta driver like vfio-pci. However, the current implementation prevents any use of drivers_probe with the VF while sriov_drivers_autoprobe=0. This blocks the now current general practice of setting driver_override followed by using drivers_probe to bind a device to a specified driver.
The kernel never automatically sets a driver_override therefore it seems we can assume a driver_override reflects the intent of the user. Also, probing a device using a driver_override match seems outside the scope of the 'auto' part of sriov_drivers_autoprobe. Therefore, let's allow driver_override matches regardless of sriov_drivers_autoprobe, which we can do by simply testing if a driver_override is set for a device as a 'can probe' condition.
Fixes: 0e7df22401a3 ("PCI: Add sysfs sriov_drivers_autoprobe to control VF driver binding") Link: https://lore.kernel.org/lkml/155742996741.21878.569845487290798703.stgit@gim... Link: https://lore.kernel.org/linux-pci/155672991496.20698.4279330795743262888.stg... Signed-off-by: Alex Williamson alex.williamson@redhat.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/pci/pci-driver.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -399,7 +399,8 @@ void __weak pcibios_free_irq(struct pci_ #ifdef CONFIG_PCI_IOV static inline bool pci_device_can_probe(struct pci_dev *pdev) { - return (!pdev->is_virtfn || pdev->physfn->sriov->drivers_autoprobe); + return (!pdev->is_virtfn || pdev->physfn->sriov->drivers_autoprobe || + pdev->driver_override); } #else static inline bool pci_device_can_probe(struct pci_dev *pdev)