x86/apic: Fix UP boot crash
Commit 31b3c9d72340 ("xen/x86: Implement x86_apic_ops") implemented
this:
... without considering that on UP the function pointer might be NULL.
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/n/tip-3pfty0ml4yp62phbkchichh0@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 8526317..7e67c5a 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1012,7 +1012,8 @@
init_cpu_to_node();
init_apic_mappings();
- x86_io_apic_ops.init();
+ if (x86_io_apic_ops.init)
+ x86_io_apic_ops.init();
kvm_guest_init();