Commit ce7585f3 authored May 31, 2016 by Alex Williamson

vfio/pci: Allow VPD short read

The size of the VPD area is not necessarily 4-byte aligned, so a
pci_vpd_read() might return less than 4 bytes. Zero our buffer and
accept anything other than an error. Intel X710 NICs exercise this.

Fixes: 4e1a6355 ("vfio/pci: Use kernel VPD access functions")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

parent 089f1c6b

drivers/vfio/pci/vfio_pci_config.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -749,7 +749,8 @@ static int vfio_vpd_config_write(struct vfio_pci_device *vdev, int pos,
		if (pci_write_vpd(pdev, addr & ~PCI_VPD_ADDR_F, 4, &data) != 4)
		return count;
		} else {
		if (pci_read_vpd(pdev, addr, 4, &data) != 4)
		data = 0;
		if (pci_read_vpd(pdev, addr, 4, &data) < 0)
		return count;
		*pdata = cpu_to_le32(data);
		}