fix: x86: support for new UV apic

Don't warn in read_apic_id() when preemptible but only one CPU online.

Signed-off-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/kernel/genapic_64.c b/arch/x86/kernel/genapic_64.c
index 021624c835832d81f00f1ed6ef5d5437e9303813..cbaaf69bedb29c92055e2272a12efba7f49f9ee1 100644 (file)
--- a/arch/x86/kernel/genapic_64.c
+++ b/arch/x86/kernel/genapic_64.c
@@ -83,7 +83,7 @@ unsigned int read_apic_id(void)
 {
        unsigned int id;
 
-       WARN_ON(preemptible());
+       WARN_ON(preemptible() && num_online_cpus() > 1);
        id = apic_read(APIC_ID);
        if (uv_system_type >= UV_X2APIC)
                id  |= __get_cpu_var(x2apic_extra_bits);