x86/apic: Do not init irq remapping if ioapic is disabled

native_smp_prepare_cpus
  -> default_setup_apic_routing
    -> enable_IR_x2apic
      -> irq_remapping_prepare
        -> intel_prepare_irq_remapping
          -> intel_setup_irq_remapping

So IR table is setup even if "noapic" boot parameter is added. As a result we
crash later when the interrupt affinity is set due to a half initialized
remapping infrastructure.

Prevent remap initialization when IOAPIC is disabled.

Signed-off-by: Wanpeng Li <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Joerg Roedel <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Cc: [email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index cea4fc19e8447d14fd6dcba5df94aa91f7a2332d..50c95af0f017d7ab73a5cad5dc226b1bf5d9cf60 100644 (file)
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1623,6 +1623,9 @@ void __init enable_IR_x2apic(void)
        unsigned long flags;
        int ret, ir_stat;
 
+       if (skip_ioapic_setup)
+               return;
+
        ir_stat = irq_remapping_prepare();
        if (ir_stat < 0 && !x2apic_supported())
                return;