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>

1 files changed, 3 insertions, 2 deletions

diff --git a/drivers/net/myri10ge/myri10ge.c b/drivers/net/myri10ge/myri10ge.c
index 9165a55f8111..6526214f69d9 100644
--- 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");