From 17638db1b88184d8895f3f4551c936d7480a1d3f Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Wed, 4 Sep 2013 10:58:52 -0600 Subject: vfio-pci: Test for extended config space Having PCIe/PCI-X capability isn't enough to assume that there are extended capabilities. Both specs define that the first capability header is all zero if there are no extended capabilities. Testing for this avoids an erroneous message about hiding capability 0x0 at offset 0x100. Signed-off-by: Alex Williamson --- drivers/vfio/pci/vfio_pci_config.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'drivers/vfio') diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c index affa34745be..ffd0632c3cb 100644 --- a/drivers/vfio/pci/vfio_pci_config.c +++ b/drivers/vfio/pci/vfio_pci_config.c @@ -1012,6 +1012,7 @@ static int vfio_vc_cap_len(struct vfio_pci_device *vdev, u16 pos) static int vfio_cap_len(struct vfio_pci_device *vdev, u8 cap, u8 pos) { struct pci_dev *pdev = vdev->pdev; + u32 dword; u16 word; u8 byte; int ret; @@ -1025,7 +1026,9 @@ static int vfio_cap_len(struct vfio_pci_device *vdev, u8 cap, u8 pos) return pcibios_err_to_errno(ret); if (PCI_X_CMD_VERSION(word)) { - vdev->extended_caps = true; + /* Test for extended capabilities */ + pci_read_config_dword(pdev, PCI_CFG_SPACE_SIZE, &dword); + vdev->extended_caps = (dword != 0); return PCI_CAP_PCIX_SIZEOF_V2; } else return PCI_CAP_PCIX_SIZEOF_V0; @@ -1037,9 +1040,11 @@ static int vfio_cap_len(struct vfio_pci_device *vdev, u8 cap, u8 pos) return byte; case PCI_CAP_ID_EXP: - /* length based on version */ - vdev->extended_caps = true; + /* Test for extended capabilities */ + pci_read_config_dword(pdev, PCI_CFG_SPACE_SIZE, &dword); + vdev->extended_caps = (dword != 0); + /* length based on version */ if ((pcie_caps_reg(pdev) & PCI_EXP_FLAGS_VERS) == 1) return PCI_CAP_EXP_ENDPOINT_SIZEOF_V1; else -- cgit v1.2.3-70-g09d2