From 69c89efb51510b3dc0fa336f7fa257c6e1799ee4 Mon Sep 17 00:00:00 2001 From: Suresh Siddha Date: Fri, 29 Jan 2010 11:42:20 -0800 Subject: [PATCH] x86, irq: Update the vector domain for legacy irqs handled by io-apic In the recent change of not reserving IRQ0_VECTOR..IRQ15_VECTOR's on all cpu's, we start with irq 0..15 getting directed to (and handled on) cpu-0. In the logical flat mode, once the AP's are online (and before irqbalance comes into picture), kernel intends to handle these IRQ's on any cpu (as the logical flat mode allows to specify multiple cpu's for the irq destination and the chipset based routing can deliver to the interrupt to any one of the specified cpu's). This was broken with our recent change, which was ending up using only cpu 0 as the destination, even when the kernel was specifying to use all online cpu's for the logical flat mode case. Fix this by updating vector allocation domain (cfg->domain) for legacy irqs, when the IO-APIC handles them. Signed-off-by: Suresh Siddha LKML-Reference: <20100129194330.207790269@sbs-t61.sc.intel.com> Tested-by: Li Zefan Cc: Yinghai Lu Cc: Eric W. Biederman Signed-off-by: H. Peter Anvin --- arch/x86/kernel/apic/io_apic.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 1a30587a6bc2..2430b31c9857 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -1428,6 +1428,14 @@ static void setup_IO_APIC_irq(int apic_id, int pin, unsigned int irq, struct irq cfg = desc->chip_data; + /* + * For legacy irqs, cfg->domain starts with cpu 0 for legacy + * controllers like 8259. Now that IO-APIC can handle this irq, update + * the cfg->domain. + */ + if (irq < nr_legacy_irqs && cpumask_test_cpu(0, cfg->domain)) + apic->vector_allocation_domain(0, cfg->domain); + if (assign_irq_vector(irq, cfg, apic->target_cpus())) return;