From: Wanpeng Li Date: Tue, 23 Aug 2016 12:07:19 +0000 (+0800) Subject: x86/apic: Do not init irq remapping if ioapic is disabled X-Git-Tag: firefly_0821_release~176^2~4^2~31^2~18 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=2e133f2d2cf40736ebc028ffa11dd907dc0753eb;p=firefly-linux-kernel-4.4.55.git x86/apic: Do not init irq remapping if ioapic is disabled commit 2e63ad4bd5dd583871e6602f9d398b9322d358d9 upstream. 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 Cc: Peter Zijlstra Cc: Joerg Roedel Link: http://lkml.kernel.org/r/1471954039-3942-1-git-send-email-wanpeng.li@hotmail.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 2f69e3b184f6..a3e1f8497f8c 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1587,6 +1587,9 @@ 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;