On Wed, Jan 07, 2015 at 11:37:52PM +0800, Jiang Liu wrote:
> On 2015/1/7 22:50, Konrad Rzeszutek Wilk wrote:
> > On Wed, Jan 07, 2015 at 02:13:49PM +0800, Jiang Liu wrote:
> >> Commit b81975eade8c ("x86, irq: Clean up irqdomain transition code")
> >> breaks xen IRQ allocation because xen_smp_prepare_cpus() doesn't invoke
> >> setup_IO_APIC(), so no irqdomains created for IOAPICs and
> >> mp_map_pin_to_irq() fails at the very beginning.
> >> --- a/arch/x86/kernel/apic/io_apic.c
> >> +++ b/arch/x86/kernel/apic/io_apic.c
> >> @@ -2369,31 +2369,29 @@ static void ioapic_destroy_irqdomain(int idx)
> >> ioapics[idx].pin_info = NULL;
> >> }
> >>
> >> -void __init setup_IO_APIC(void)
> >> +void __init setup_IO_APIC(bool xen_smp)
> >> {
> >> int ioapic;
> >>
> >> - /*
> >> - * calling enable_IO_APIC() is moved to setup_local_APIC for BP
> >> - */
> >> - io_apic_irqs = nr_legacy_irqs() ? ~PIC_IRQS : ~0UL;
> >> + if (!xen_smp) {
> >> + apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");
> >> + io_apic_irqs = nr_legacy_irqs() ? ~PIC_IRQS : ~0UL;
> >> +
> >> + /* Set up IO-APIC IRQ routing. */
> >> + x86_init.mpparse.setup_ioapic_ids();
> >> + sync_Arb_IDs();
> >> + }
> >
> >
> > Is there a specific reason that this cannot run in all cases?
> >
> > What I am asking is why are we doing a special case here? The description
> > at the top implied that we were just missing an call to
> > setup_IO_APIC..
> Hi Konrad,
> I'm not very familiar with Xen IRQ yet, so I just enabled the
> code to create irqdomains for IOAPICs and keep other part as is. I will
> try to check whether we could enable other part all together:)
If you want you can (privately) send me (or Sander) and patch that I would
be happy to test out. It is quite amusing that I have not used the power
button for quite a while - I always rebooting the machine to install
a new kernel :-)
> Regards!
> Gerry
>
> >
> >>
> >> - apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");
> >> for_each_ioapic(ioapic)
> >> BUG_ON(mp_irqdomain_create(ioapic));
> >> -
> >> - /*
> >> - * Set up IO-APIC IRQ routing.
> >> - */
> >> - x86_init.mpparse.setup_ioapic_ids();
> >> -
> >> - sync_Arb_IDs();
> >> setup_IO_APIC_irqs();
> >> - init_IO_APIC_traps();
> >> - if (nr_legacy_irqs())
> >> - check_timer();
> >> -
> >> ioapic_initialized = 1;
> >> +
> >> + if (!xen_smp) {
> >> + init_IO_APIC_traps();
> >> + if (nr_legacy_irqs())
> >> + check_timer();
> >> + }
> >> }
> >>
> >> /*
> >> diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
> >> index 4c071aeb8417..7eb0283901fa 100644
> >> --- a/arch/x86/xen/smp.c
> >> +++ b/arch/x86/xen/smp.c
> >> @@ -326,7 +326,10 @@ static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
> >>
> >> xen_raw_printk(m);
> >> panic(m);
> >> + } else {
> >> + setup_IO_APIC(true);
> >> }
> >> +
> >> xen_init_lock_cpu(0);
> >>
> >> smp_store_boot_cpu_info();
> >> --
> >> 1.7.10.4
> >>
> > --
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