--- ubuntu-gutsy.orig/arch/i386/pci/fixup.c     2008-04-09 15:17:23.000000000 +0100
+++ ubuntu-gutsy/arch/i386/pci/fixup.c  2008-04-09 15:20:05.000000000 +0100
@@ -9,6 +9,19 @@
 #include "pci.h"
 
 
+/* TJ: Added to work around duplicate bus-scan and subsequent PERC 2 controller failure
+ * See http://bugzilla.kernel.org/show_bug.cgi?id=10396 */
+static struct dmi_system_id __devinitdata i450nx_dmi_table[] = {
+       {
+               .ident = "Dell-PowerEdge-6300",
+               .matches = {
+                       DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
+                       DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 6300"),
+               },
+       },
+       {}
+};
+
 static void __devinit pci_fixup_i450nx(struct pci_dev *d)
 {
        /*
@@ -17,6 +30,18 @@
        int pxb, reg;
        u8 busno, suba, subb;
 
+       /* TJ: Added to work around duplicate bus-scan and subsequent Dell 
+        * PERC 2 controller failure.
+        * See http://bugzilla.kernel.org/show_bug.cgi?id=10396
+        * 
+        * NOTE: A matching entry causes a return without *doing anything* 
+        * - the opposite of this logic in other cases.
+        */
+               if (dmi_check_system(i450nx_dmi_table)) {
+                       DBG("i450NX PXB fix-up ignored - found %s\n", i450nx_dmi_table.ident);
+                       return; /* doesn't apply to matched systems */
+               }
+
        printk(KERN_WARNING "PCI: Searching for i450NX host bridges on %s\n", pci_name(d));
        reg = 0xd0;
        for(pxb=0; pxb<2; pxb++) {