From: Konrad Rzeszutek Wilk Date: Thu, 11 Feb 2016 21:10:23 +0000 (-0500) Subject: xen/pciback: Check PF instead of VF for PCI_COMMAND_MEMORY X-Git-Tag: v4.1.20~81 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a7b4133de42f7eb7a926e1a5a1aaf0c1e7bfad12;p=thirdparty%2Fkernel%2Fstable.git xen/pciback: Check PF instead of VF for PCI_COMMAND_MEMORY [ Upstream commit d52a24819677bbb45eb1ce93a42daa1ae6c4d61d ] commit 8d47065f7d1980dde52abb874b301054f3013602 upstream. Commit 408fb0e5aa7fda0059db282ff58c3b2a4278baa0 (xen/pciback: Don't allow MSI-X ops if PCI_COMMAND_MEMORY is not set) prevented enabling MSI-X on passed-through virtual functions, because it checked the VF for PCI_COMMAND_MEMORY but this is not a valid bit for VFs. Instead, check the physical function for PCI_COMMAND_MEMORY. Signed-off-by: Konrad Rzeszutek Wilk Reviewed-by: Jan Beulich Signed-off-by: David Vrabel Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- diff --git a/drivers/xen/xen-pciback/pciback_ops.c b/drivers/xen/xen-pciback/pciback_ops.c index 7d858ff958eda..9cf4653b6bd7a 100644 --- a/drivers/xen/xen-pciback/pciback_ops.c +++ b/drivers/xen/xen-pciback/pciback_ops.c @@ -212,8 +212,9 @@ int xen_pcibk_enable_msix(struct xen_pcibk_device *pdev, /* * PCI_COMMAND_MEMORY must be enabled, otherwise we may not be able * to access the BARs where the MSI-X entries reside. + * But VF devices are unique in which the PF needs to be checked. */ - pci_read_config_word(dev, PCI_COMMAND, &cmd); + pci_read_config_word(pci_physfn(dev), PCI_COMMAND, &cmd); if (dev->msi_enabled || !(cmd & PCI_COMMAND_MEMORY)) return -ENXIO;