Merge branch 'linus' into xen-64bit

1 files changed, 21 insertions, 5 deletions

diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c
index a4665f37cfc..a0e11c0cc87 100644
--- a/arch/x86/kernel/early-quirks.c
+++ b/arch/x86/kernel/early-quirks.c
@@ -120,7 +120,18 @@ static struct chipset early_qrk[] __initdata = {
 	{}
 };
 
-static void __init check_dev_quirk(int num, int slot, int func)
+/**
+ * check_dev_quirk - apply early quirks to a given PCI device
+ * @num: bus number
+ * @slot: slot number
+ * @func: PCI function
+ *
+ * Check the vendor & device ID against the early quirks table.
+ *
+ * If the device is single function, let early_quirks() know so we don't
+ * poke at this device again.
+ */
+static int __init check_dev_quirk(int num, int slot, int func)
 {
 	u16 class;
 	u16 vendor;
@@ -131,7 +142,7 @@ static void __init check_dev_quirk(int num, int slot, int func)
 	class = read_pci_config_16(num, slot, func, PCI_CLASS_DEVICE);
 
 	if (class == 0xffff)
-		return;
+		return -1; /* no class, treat as single function */
 
 	vendor = read_pci_config_16(num, slot, func, PCI_VENDOR_ID);
 
@@ -154,7 +165,9 @@ static void __init check_dev_quirk(int num, int slot, int func)
 	type = read_pci_config_byte(num, slot, func,
 				    PCI_HEADER_TYPE);
 	if (!(type & 0x80))
-		return;
+		return -1;
+
+	return 0;
 }
 
 void __init early_quirks(void)
@@ -167,6 +180,9 @@ void __init early_quirks(void)
 	/* Poor man's PCI discovery */
 	for (num = 0; num < 32; num++)
 		for (slot = 0; slot < 32; slot++)
-			for (func = 0; func < 8; func++)
-				check_dev_quirk(num, slot, func);
+			for (func = 0; func < 8; func++) {
+				/* Only probe function 0 on single fn devices */
+				if (check_dev_quirk(num, slot, func))
+					break;
+			}
 }