Re: [PATCH 3.10 005/103] irqchip: Gic: Support forced affinity setting

Greg Kroah-Hartman
2014-06-05T18:01:45Z

On Thu, Jun 05, 2014 at 05:05:00PM +0100, Mark Rutland wrote:
> Hi Greg,
>
> On Thu, Jun 05, 2014 at 12:24:28AM +0100, Greg Kroah-Hartman wrote:
> > 3.10-stable review patch. If anyone has any objections, please let me know.
> >
> > ------------------
> >
> > From: Thomas Gleixner <tglx@linutronix.de>
> >
> > commit ffde1de64012c406dfdda8690918248b472f24e4 upstream.
> >
> > To support the affinity setting of per cpu timers in the early startup
> > of a not yet online cpu, implement the force logic, which disables the
> > cpu online check.
> >
> > Tagged for stable to allow a simple fix of the affected SoC clock
> > event drivers.
>
> This patch alone has the possiblity of breaking CPU hotplug on arm and
> arm64 (specifically it breaks hot unplugging CPU0 where interrupts may
> be left targetting the offline CPU).
>
> For arm64 [1] that's fixed by commit 601c942176d8 (arm64: use
> cpu_online_mask when using forced irq_set_affinity).

Thanks, I'll apply that to the 3.14-stable tree, but, it doesn't seem
relevant at all for 3.10-stable as arch/arm64/kernel/irq.c doesn't do
anything with cpumask or set_affinity. If it's relevant for 3.10,
please provide a backported version.

> Unfortunately there is not an equivalent fix for arm - Russell objected
> to the approach [2,3,4], and that's not yet settled.

Ok, be sure to cc: stable on the patch when it goes into the tree and
I'll pick it up then.

thanks,

greg k-h