Re: [PATCH] power: Change device_wakeup_enable() to check for null dev_name(dev)

On Friday, November 15, 2013 05:16:31 PM Shuah Khan wrote:

On 11/15/2013 05:21 PM, Rafael J. Wysocki wrote:

quoted

On Friday, November 15, 2013 05:03:57 PM Shuah Khan wrote:

quoted

device_wakeup_enable() uses dev_name(dev) as the wakeup source name.
When it gets called with a device with its name not yet set, ws structure
with ws->name = NULL gets created.

When kernel is booted with wakeup_source_activate enabled, it will panic
when the trace point code tries to derefernces ws->name.

Change device_wakeup_enable() to check for dev_name(dev) null condition
and return -EINVAL to avoid panics when device_wakeup_enable() gets called
before device is fully initialized with its name.

  		return -EINVAL;

quoted

Can you please use WARN_ON(!dev_name(dev)) here?  While I agree that it is a
bad idea to crash the kernel because dev has no name, that indicates a driver
bug that shouldn't be too easy to ignore.

Thanks!

Right. ok I will re-cut the patch with WARN_ON and send it. fyi I did 
send fix for the driver (power_supply) as well.

http://www.kernelhub.org/?msg=362354&p=2

That's OK (thanks for taking care of this), but there may be more brilliant
stuff like that in the future and people should see right away that something's
wrong in those cases.

Rafael