On Mon, 2015-08-03 at 19:32 +0800, Chenhui Zhao wrote:
> >
> On Sat, Aug 1, 2015 at 7:59 AM, Scott Wood <scottw...@freescale.com>
> wrote:
> >
> > Could you explain irq_mask()? Why would there still be IRQs destined
> > for
> > this CPU at this point?
>
> This function just masks irq by setting the registers in RCPM (for
> example, RCPM_CPMIMR, RCPM_CPMCIMR). Actually, all irqs to this CPU
> have been migrated to other CPUs.
So why do we need to set those bits in RCPM? Is it just caution?
> > @@ -431,21 +415,9 @@ void __init mpc85xx_smp_init(void)
> > > smp_85xx_ops.probe = NULL;
> > > }
> > >
> > > - np = of_find_matching_node(NULL, mpc85xx_smp_guts_ids);
> > > - if (np) {
> > > - guts = of_iomap(np, 0);
> > > - of_node_put(np);
> > > - if (!guts) {
> > > - pr_err("%s: Could not map guts node
> > > address\n",
> > > -
> > > __func__);
> > > - return;
> > > - }
> > > - smp_85xx_ops.give_timebase = mpc85xx_give_timebase;
> > > - smp_85xx_ops.take_timebase = mpc85xx_take_timebase;
> > > #ifdef CONFIG_HOTPLUG_CPU
> > > - ppc_md.cpu_die = smp_85xx_mach_cpu_die;
> > > + ppc_md.cpu_die = qoriq_cpu_dying;
> > > #endif
> >
> > Shouldn't you make sure there's a valid qoriq_pm_ops before setting
> > cpu_die()? Or make sure that qoriq_cpu_dying() works regardless.
> >
> > -Scott
>
> This patch is just for e500v2. The following patches will handle the
> case of e500mc, e5500 and e6500.
What stops a user from trying to use cpu hotplug on unsupported cpus, or in a
virtualized environment, and crashing here?
-Scott
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