[Qemu-devel] [PATCH stable-0.15 13/36] Fix X86 CPU topology in KVM mode

[Andreas Färber]

From: Bharata B Rao <address@hidden>

apic id returned to guest kernel in ebx for cpuid(function=1) depends on
CPUX86State->cpuid_apic_id which gets populated after the cpuid information
is cached in the host kernel. This results in broken CPU topology in guest.

Fix this by setting cpuid_apic_id before cpuid information is passed to
the host kernel. This is done by moving the setting of cpuid_apic_id
to cpu_x86_init() where it will work for both KVM as well as TCG modes.

Acked-by: Jan Kiszka <address@hidden>
Signed-off-by: Bharata B Rao <address@hidden>
Signed-off-by: Anthony Liguori <address@hidden>
(cherry picked from commit f2209eb854a016eabc444b45f6d6b1636949141f)

Signed-off-by: Bruce Rogers <address@hidden>
Signed-off-by: Andreas Färber <address@hidden>
---
 hw/pc.c              |    1 -
 target-i386/helper.c |    1 +
 2 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/hw/pc.c b/hw/pc.c
index a3e8539..14ce684 100644
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -931,7 +931,6 @@ static CPUState *pc_new_cpu(const char *cpu_model)
         exit(1);
     }
     if ((env->cpuid_features & CPUID_APIC) || smp_cpus > 1) {
-        env->cpuid_apic_id = env->cpu_index;
         env->apic_state = apic_init(env, env->cpuid_apic_id);
     }
     qemu_register_reset(pc_cpu_reset, env);
diff --git a/target-i386/helper.c b/target-i386/helper.c
index e9be104..829c1da 100644
--- a/target-i386/helper.c
+++ b/target-i386/helper.c
@@ -1258,6 +1258,7 @@ CPUX86State *cpu_x86_init(const char *cpu_model)
         cpu_x86_close(env);
         return NULL;
     }
+    env->cpuid_apic_id = env->cpu_index;
     mce_init(env);
 
     qemu_init_vcpu(env);
-- 
1.7.7