VF BARs are read-only zeroes according to SRIOV spec, the normal way(writing BARs) of allocating resources wouldn't be applied to VFs. The VFs' resources would be allocated when we enable SR-IOV capability. So we should not try to reassign alignment after we enable VFs. It's meaningless and will release the allocated resources which leads to a bug. Signed-off-by: Yongji Xie <xyjxie@xxxxxxxxxxxxxxxxxx> --- drivers/pci/pci.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 2d85a96..b8357d7 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5048,6 +5048,15 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev) resource_size_t align, size; u16 command; + /* + * VF BARs are RO zero according to SR-IOV spec 3.4.1.11. Their + * resources would be allocated when we enable them and not be + * re-allocated any more. So we should never try to reassign + * VF's alignment here. + */ + if (dev->is_virtfn) + return; + /* check if specified PCI is target device to reassign */ align = pci_specified_resource_alignment(dev); if (!align) -- 1.7.9.5 -- 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
