Bunch of machines are not booting in next again, GPIO regression?

[Michael Welling]

On Wed, Feb 17, 2016 at 01:55:43PM -0600, Josh Cartwright wrote:
> On Wed, Feb 17, 2016 at 11:27:55AM -0800, Tony Lindgren wrote:
> > Hi Linus,
> > 
> > Looks like ff2b13592299 ("gpio: make the gpiochip a real device")
> > broke booting on all omaps, and probably other machines too according
> > to this:
> > 
> > https://kernelci.org/boot/all/job/next/kernel/next-20160217/
> > 
> > So far we've gone from 1 failed machine with next-20160216 to
> > 18 failed machines with next-20160217.
> > 
> > The error I'm getting on omaps is below with debug_ll enable,
> > any ideas?
> 
> Hey Tony-
> 
> Looks like the newly allocated gpio_device object isn't zeroed,
> confusing dev_set_name.  Can you give this a try?
> 
>   Josh
> 
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index d8511cd..59f0045 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -435,7 +435,7 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
>  	 * First: allocate and populate the internal stat container, and
>  	 * set up the struct device.
>  	 */
> -	gdev = kmalloc(sizeof(*gdev), GFP_KERNEL);
> +	gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
>  	if (!gdev)
>  		return -ENOMEM;
>  	gdev->dev.bus = &gpio_bus_type;

As you can see by my post on the GPIO mailing list, a boot failure
was occurring on the Dragonboard 410C:
http://permalink.gmane.org/gmane.linux.kernel.gpio/14360

With the above patch the board now boots. Good catch.