driver core: Print device when resources present in really_probe()
authorGeert Uytterhoeven <geert+renesas@glider.be>
Fri, 6 Dec 2019 13:22:19 +0000 (14:22 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 14 Jan 2020 15:14:48 +0000 (16:14 +0100)
If a device already has devres items attached before probing, a warning
backtrace is printed.  However, this backtrace does not reveal the
offending device, leaving the user uninformed.  Furthermore, using
WARN_ON() causes systems with panic-on-warn to reboot.

Fix this by replacing the WARN_ON() by a dev_crit() message.
Abort probing the device, to prevent doing more damage to the device's
resources.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20191206132219.28908-1-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/base/dd.c

index d811e60..b25bcab 100644 (file)
@@ -516,7 +516,10 @@ static int really_probe(struct device *dev, struct device_driver *drv)
        atomic_inc(&probe_count);
        pr_debug("bus: '%s': %s: probing driver %s with device %s\n",
                 drv->bus->name, __func__, drv->name, dev_name(dev));
-       WARN_ON(!list_empty(&dev->devres_head));
+       if (!list_empty(&dev->devres_head)) {
+               dev_crit(dev, "Resources present before probing\n");
+               return -EBUSY;
+       }
 
 re_probe:
        dev->driver = drv;