Drivers: hv: vmbus: incorrect device name is printed when child device is unregistered

commit 84672369ffb98a51d4ddf74c20a23636da3ad615 upstream.

Whenever a device is unregistered in vmbus_device_unregister (drivers/hv/vmbus_drv.c), the device name in the log message may contain garbage as the memory has already been freed by the time pr_info is called. Log example:
 [ 3149.170475] hv_vmbus: child device àõsèè0_5 unregistered

By logging the message just before calling device_unregister, the correct device name is printed:
[ 3145.034652] hv_vmbus: child device vmbus_0_5 unregistered

Also changing register & unregister messages to debug to avoid unnecessarily cluttering the kernel log.

Signed-off-by: Fernando M Soto <fsoto@bluecatnetworks.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 44442d5..f58067f 100644 (file)
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -681,7 +681,7 @@ int vmbus_device_register(struct hv_device *child_device_obj)
        if (ret)
                pr_err("Unable to register child device\n");
        else
-               pr_info("child device %s registered\n",
+               pr_debug("child device %s registered\n",
                        dev_name(&child_device_obj->device));
 
        return ret;
@@ -693,14 +693,14 @@ int vmbus_device_register(struct hv_device *child_device_obj)
  */
 void vmbus_device_unregister(struct hv_device *device_obj)
 {
+       pr_debug("child device %s unregistered\n",
+               dev_name(&device_obj->device));
+
        /*
         * Kick off the process of unregistering the device.
         * This will call vmbus_remove() and eventually vmbus_device_release()
         */
        device_unregister(&device_obj->device);
-
-       pr_info("child device %s unregistered\n",
-               dev_name(&device_obj->device));
 }