[PATCH v3 2/7] PCI: Ignore enforced alignment to VF BARs

From: Yongji Xie
Date: Thu Jun 30 2016 - 06:54:33 EST


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 | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index be8f72c..6ae02de 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4822,6 +4822,10 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev)
resource_size_t align, size;
u16 command;

+ /* We should never try to reassign VF's alignment */
+ 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