USB: Fix race condition when removing host controllers

[firefly-linux-kernel-4.4.55.git] / drivers / usb / core / devices.c

diff --git a/drivers/usb/core/devices.c b/drivers/usb/core/devices.c
index d9569658476274f34d8a51726da828d87bf44831..3440812b4a849c3d2f372e022f730ade5f5e3e6b 100644 (file)
--- a/drivers/usb/core/devices.c
+++ b/drivers/usb/core/devices.c
@@ -624,7 +624,7 @@ static ssize_t usb_device_read(struct file *file, char __user *buf,
        /* print devices for all busses */
        list_for_each_entry(bus, &usb_bus_list, bus_list) {
                /* recurse through all children of the root hub */
-               if (!bus->root_hub)
+               if (!bus_to_hcd(bus)->rh_registered)
                        continue;
                usb_lock_device(bus->root_hub);
                ret = usb_device_dump(&buf, &nbytes, &skip_bytes, ppos,