On Wed, Dec 21, 2011 at 05:59:07PM +0800, Barry Song wrote: > 2011/12/21 Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx>: > > cpu hotplug is basically totally buggered - the preconditions placed > > upon the bringup code path are basically impossible to satisfy in any > > shape or form at the moment. > > > > There's the requirement that the secondary CPU is marked online and > > active before interrupts are enabled for the thread migration stuff > > to behave correctly. However, this is incompatible with smp_call_function() > > which will wait for online CPUs to respond to an IPI - which this one > > won't because interrupts are disabled. > > > > I think there was some discussion about how to fix this but I don't > > recall the details. > > thanks, Russell. then could i think this is an ARM-kernel-specific bug > which exists on all ARM SMP chips for the moment? > and that bug doesn't happen on x86: I don't think so. There's nothing ARM specific about it. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
