Index: pci.c
===================================================================
--- pci.c	(revision 220127)
+++ pci.c	(working copy)
@@ -108,7 +108,7 @@
 			    uint64_t address, uint32_t data);
 static void		pci_mask_msix(device_t dev, u_int index);
 static void		pci_unmask_msix(device_t dev, u_int index);
-static int		pci_msi_blacklisted(void);
+static int		pci_msi_blacklisted(device_t child);
 static void		pci_resume_msi(device_t dev);
 static void		pci_resume_msix(device_t dev);
 static int		pci_remap_intr_method(device_t bus, device_t dev,
@@ -1300,7 +1300,7 @@
 		return (ENXIO);
 
 	/* If MSI is blacklisted for this system, fail. */
-	if (pci_msi_blacklisted())
+	if (pci_msi_blacklisted(child))
 		return (ENXIO);
 
 	/* MSI-X capability present? */
@@ -1887,8 +1887,9 @@
  * that give the motherboard manufacturer and model number.
  */
 static int
-pci_msi_blacklisted(void)
+pci_msi_blacklisted(device_t child)
 {
+	struct pci_devinfo *dinfo;
 	device_t dev;
 
 	if (!pci_honor_msi_blacklist)
@@ -1907,6 +1908,18 @@
 	dev = pci_find_bsf(0, 0, 0);
 	if (dev != NULL)
 		return (pci_msi_device_blacklisted(dev));
+
+	/*
+	 * Blacklist HyperTransport devices on systems with Nvidia
+	 * chipsets if the device at 0:0:0:0 is not a HyperTransport
+	 * slave.
+	 */
+	if (pci_find_cap(child, PCIY_HT, NULL) == 0 && dev != NULL &&
+	    pci_get_vendor(dev) == 0x10de) {
+		dinfo = device_get_ivars(dev);
+		if (dinfo->cfg.ht.ht_slave == 0)
+			return (1);
+	}
 	return (0);
 }
 
@@ -1938,7 +1951,7 @@
 		return (ENXIO);
 
 	/* If MSI is blacklisted for this system, fail. */
-	if (pci_msi_blacklisted())
+	if (pci_msi_blacklisted(child))
 		return (ENXIO);
 
 	/* MSI capability present? */