Shutdown problem in SMP system happened on Tegra20

[Russell King - ARM Linux]

On Sat, Aug 25, 2012 at 03:36:27PM +0800, Shawn Guo wrote:
> On Fri, Aug 24, 2012 at 07:21:33PM +0100, Russell King - ARM Linux wrote:
> > Why not just ensure that CONFIG_PM_SLEEP_SMP is enabled if your platform
> > requires that the lowest CPU number be the CPU dealing with reboot?
> 
> I have CONFIG_PM_SLEEP_SMP enabled for imx6q, but still see the imx6q
> restart hook running on cpu1 than cpu0.  It seems that
> disable_nonboot_cpus is only called in kernel_power_off but never
> kernel_restart.  We should probably patch kernel_restart or
> machine_restart to have disable_nonboot_cpus called? 

Remember that this path gets called from IRQ context which makes calling
functions which sleep very dodgy.