On Wed, Sep 14, 2011 at 2:15 AM, Dave Martin [off-list ref] wrote:

<snip>

With regard to Thumb-2 kernels, what code is responsible for
performing the jump to tegra_secondary_startup?

arch/arm/mach-tegra/platsmp.c puts the physical address of
tegra_secondary_startup into the reset vector, and then brings the cpu
out of reset.  As far as I know, it is always in ARM mode, but it is
possible that it comes through ROM code that ends with a bx, allowing
it to be entered in Thumb mode.

If the jump is done by making an exception return from some firmware,
you may find you hit tegra_secondary_starup in ARM state, and
everything will go horribly wrong...

It could be worth making the secondary kernel entry point ARM code
unconditionally (just as is now done for the primary kernel entry
point).

That seems safest.

Cheers
---Dave

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel at lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel