myri10ge: fix potential infinite loop in enable_ecrc

Fix another potential for an infinite loop while looking for the
root port in myri10ge_enable_ecrc().

Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Andrew Gallatin <gallatin@myri.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

diff --git a/drivers/net/myri10ge/myri10ge.c b/drivers/net/myri10ge/myri10ge.c
index 9165a55f8111d5dcaf117a2b36f422bdcee0b056..6526214f69d9b5e662fef019d864fa69355cb5f4 100644 (file)
--- a/drivers/net/myri10ge/myri10ge.c
+++ b/drivers/net/myri10ge/myri10ge.c
@@ -2657,13 +2657,14 @@ static void myri10ge_enable_ecrc(struct myri10ge_priv *mgp)
        ext_type = (val & PCI_EXP_FLAGS_TYPE) >> 4;
        if (ext_type != PCI_EXP_TYPE_ROOT_PORT) {
                if (myri10ge_ecrc_enable > 1) {
-                       struct pci_dev *old_bridge = bridge;
+                       struct pci_dev *prev_bridge, *old_bridge = bridge;
 
                        /* Walk the hierarchy up to the root port
                         * where ECRC has to be enabled */
                        do {
+                               prev_bridge = bridge;
                                bridge = bridge->bus->self;
-                               if (!bridge) {
+                               if (!bridge || prev_bridge == bridge) {
                                        dev_err(dev,
                                                "Failed to find root port"
                                                " to force ECRC\n");