From: Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 15 Jan 2015 21:22:32 +0000 (+0000)
Subject: x86/ioapic: Add proper checks to setp/enable_IO_APIC()
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=a46f5c89274245e42834dc976896444efd53ccdc;p=linux-beck.git

x86/ioapic: Add proper checks to setp/enable_IO_APIC()

No point to have the same checks at every call site. Add them to the
functions, so they can be called unconditionally.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211703.490719938@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index e5e00f509f03..f4dc2462a1ac 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1507,7 +1507,10 @@ void __init enable_IO_APIC(void)
 	int i8259_apic, i8259_pin;
 	int apic, pin;
 
-	if (!nr_legacy_irqs())
+	if (skip_ioapic_setup)
+		nr_ioapics = 0;
+
+	if (!nr_legacy_irqs() || !nr_ioapics)
 		return;
 
 	for_each_ioapic_pin(apic, pin) {
@@ -2373,9 +2376,9 @@ void __init setup_IO_APIC(void)
 {
 	int ioapic;
 
-	/*
-	 * calling enable_IO_APIC() is moved to setup_local_APIC for BP
-	 */
+	if (skip_ioapic_setup || !nr_ioapics)
+		return;
+
 	io_apic_irqs = nr_legacy_irqs() ? ~PIC_IRQS : ~0UL;
 
 	apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");