x86: don't call read_apic_id if !cpu_has_apic

should not call that if apic is disabled.

[ Impact: fix crash on certain UP configs ]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
LKML-Reference: <4A09CCBB.2000306@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 6 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index c1caefc82e62..017c600e05ab 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -761,6 +761,12 @@ static void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
         if (this_cpu->c_identify)
                 this_cpu->c_identify(c);
 
+        /* Clear/Set all flags overriden by options, after probe */
+        for (i = 0; i < NCAPINTS; i++) {
+                c->x86_capability[i] &= ~cpu_caps_cleared[i];
+                c->x86_capability[i] |= cpu_caps_set[i];
+        }
+
 #ifdef CONFIG_X86_64
         c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
 #endif