x86, NMI: NMI-selftest should handle the UP case properly

If no remote cpus are online, then just quietly skip the remote
IPI test for now.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: andi@firstfloor.org
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: robert.richter@amd.com
Link: http://lkml.kernel.org/r/20111206180859.GR1669@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/nmi_selftest.c b/arch/x86/kernel/nmi_selftest.c
index 572adb622251a075e8b592d1cf3b0ecb720140ae..1e42a23c1f2a766dbf3ced1a0db605d4b4a7b0a6 100644 (file)
--- a/arch/x86/kernel/nmi_selftest.c
+++ b/arch/x86/kernel/nmi_selftest.c
@@ -90,7 +90,8 @@ static void remote_ipi(void)
 {
        cpumask_copy(to_cpumask(nmi_ipi_mask), cpu_online_mask);
        cpumask_clear_cpu(smp_processor_id(), to_cpumask(nmi_ipi_mask));
-       test_nmi_ipi(to_cpumask(nmi_ipi_mask));
+       if (!cpumask_empty(nmi_ipi_mask))
+               test_nmi_ipi(to_cpumask(nmi_ipi_mask));
 }
 
 static void local_ipi(void)