On 6/12/19 11:19 AM, Alex Williamson wrote:
On Wed, 12 Jun 2019 10:06:47 -0700 sathyanarayanan.kuppusw...@linux.intel.com wrote:From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppusw...@linux.intel.com> Commit 975bb8b4dc93 ("PCI/IOV: Use VF0 cached config space size for other VFs") calculates and caches the cfg_size for VF0 device before initializing the pcie_cap of the device which results in using incorrect cfg_size for all VF devices > 0. So set pcie_cap of the device before calculating the cfg_size of VF0 device. Fixes: 975bb8b4dc93 ("PCI/IOV: Use VF0 cached config space size for other VFs") Cc: Ashok Raj <ashok....@intel.com> Suggested-by: Mike Campin <mike.cam...@intel.com> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppusw...@linux.intel.com> --- Changes since v1: * Fixed a typo in commit message. drivers/pci/iov.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 3aa115ed3a65..2869011c0e35 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -160,6 +160,7 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id) virtfn->device = iov->vf_device; virtfn->is_virtfn = 1; virtfn->physfn = pci_dev_get(dev); + virtfn->pcie_cap = pci_find_capability(virtfn, PCI_CAP_ID_EXP);if (id == 0)pci_read_vf_config_common(virtfn);Why not re-order until after we've setup pcie_cap? https://lore.kernel.org/linux-pci/20190604143617.0a226...@x1.home/T/#
pci_read_vf_config_common() also caches values for properties like class, hdr_type, susbsystem_vendor/device. These values are read/used in pci_setup_device(). So if we can use cached values in pci_setup_device(), we don't have to read them from registers twice for each device.
Thanks, Alex
-- Sathyanarayanan Kuppuswamy Linux kernel developer
