Re: [PATCH] driver core: add a debugfs entry to show deferred devices

[Andy Shevchenko]

On Wed, Jun 20, 2018 at 1:51 AM, Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> On Tue, Jun 19, 2018 at 10:59:14PM +0200, Javier Martinez Canillas wrote:
>> For debugging purposes it may be useful to know what are the devices whose
>> probe function was deferred. Add a debugfs entry showing that information.
>>
>>   $ cat /sys/kernel/debug/deferred_devices
>>   48070000.i2c:twl@48:bci
>>   musb-hdrc.0.auto
>>   omapdrm.0


> And what is the use of this file?  What can you do with this
> information?  Who is going to use it?  Don't we have other deferred
> probe debugging somewhere else?

Indeed.

Javier, have you tried to add 'initcall_debug' to a kernel command
line followed by 'dyndbg="file drivers/base/dd.c +p"'?

-- 
With Best Regards,
Andy Shevchenko