Re: Crash introduced by commit b8b2c7d845d5 ("base/platform: assert that dev_pm_domain callbacks are called unconditionally")

[Uwe Kleine-König]

Hello Alan,

On Tue, Jan 19, 2016 at 01:22:22PM -0500, Alan Stern wrote:
> 
> Your commit causes my ASUS laptop to crash during early boot.  The 
> problem occurs in platform_drv_probe(), affecting both the alarmtimer 
> and the asus_laptop platform drivers (I can't tell which is the 
> critical one).
> 
> The old code would not call platform_drv_probe() at all, and probing
> would always succeed immediately because these drivers have no probe
> routine.  But with the new code, platform_drv_probe() does run.  The
> call to of_clk_set_defaults() returns -ENODEV, as does the call to
> dev_pm_domain_attach().  The call to drv->probe() gets skipped, of 
> course.  The final return value is -ENODEV, and so probing fails.  This 
> causes the kernel to crash: blank screen, NumLock LED blinking.
> 
> The patch below fixes the problem, but I'm not sure that it's the best 
> solution.  What is your advice?
You want

	http://mid.gmane.org/1449132704-9952-1-git-send-email-martin.wilck@xxxxxxxxxxxxxx

.

Greg, I'd welcome this fix in mainline and 4.4.x.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |