[RFC/PATCH] arm: do not skip SMP init calls on SMP_ON_UP case
nyushchenko at dev.rtsoft.ru
Tue Nov 24 07:05:37 PST 2015
> I'm still trying to understand what is going on, and my printk()s show
> that this is not entirely true.
> When smp_init() is entered on mainline om imx6s, cpu_possible_mask and
> cpu_present_mask both contain two cpus. These get initialized in
> arm_dt_init_cpu_maps() and stay unmodified since then.
> But cpu_online() returns 1 for cpu0 and 0 from cpu1 - thus it is
> cpu_online() check, not possible_mask or present_mask, that prevents
> cpu1 initialization attempt.
Sorry was too quick to type.
cpu_online(0) is true and cpu_online(1) is false.
It is natural, since cpu0 is already running.
Thus cpu_up(1) is entered!
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