eal: fix deadlock in hot-unplug

When device be hot-unplugged, the hot-unplug handler will be invoked by uio
remove event and the device will be detached, then kernel will sent another
pci remove event. So if there is any unlock miss, it will cause a dead lock
issue. This patch will add this missing unlock for hot-unplug handler.

Fixes: 0fc54536b14a ("eal: add failure handling for hot-unplug")

Signed-off-by: Jeff Guo <jia.guo@intel.com>

diff --git a/lib/librte_eal/linuxapp/eal/eal_dev.c b/lib/librte_eal/linuxapp/eal/eal_dev.c
index d589c69..2830c86 100644 (file)
--- a/lib/librte_eal/linuxapp/eal/eal_dev.c
+++ b/lib/librte_eal/linuxapp/eal/eal_dev.c
@@ -258,7 +258,7 @@ dev_uev_handler(__rte_unused void *param)
                        if (bus == NULL) {
                                RTE_LOG(ERR, EAL, "Cannot find bus (%s)\n",
                                        busname);
-                               return;
+                               goto failure_handle_err;
                        }
 
                        dev = bus->find_device(NULL, cmp_dev_name,
@@ -266,19 +266,23 @@ dev_uev_handler(__rte_unused void *param)
                        if (dev == NULL) {
                                RTE_LOG(ERR, EAL, "Cannot find device (%s) on "
                                        "bus (%s)\n", uevent.devname, busname);
-                               return;
+                               goto failure_handle_err;
                        }
 
                        ret = bus->hot_unplug_handler(dev);
-                       rte_spinlock_unlock(&failure_handle_lock);
                        if (ret) {
                                RTE_LOG(ERR, EAL, "Can not handle hot-unplug "
                                        "for device (%s)\n", dev->name);
-                               return;
                        }
+                       rte_spinlock_unlock(&failure_handle_lock);
                }
                rte_dev_event_callback_process(uevent.devname, uevent.type);
        }
+
+       return;
+
+failure_handle_err:
+       rte_spinlock_unlock(&failure_handle_lock);
 }
 
 int __rte_experimental