On Mon, May 23, 2016 at 6:07 PM, Russell King - ARM Linux
[off-list ref] wrote:

Read the code again.  There's three states:

1. CONFIG_SMP=n - it always returns false.
2. CONFIG_SMP=y, CONFIG_SMP_ON_UP=n - it always returns true.  Such a
   kernel can _only_ be run on SMP capable systems.
3. CONFIG_SMP=y, CONFIG_SMP_ON_UP=y - it returns depending on whether
   we detect that the CPU is SMP capable.

Yes, I meant that on imx6ul we have option 2 above with imx_v6_v7_defconfig.

Also tested option 3 and is_smp() returns true as well.

I will try to see why GIC on this SoC cannot work in SMP.