From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:51703) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R1XFP-0008OG-1Y for qemu-devel@nongnu.org; Thu, 08 Sep 2011 01:34:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1R1XFN-0005NT-QW for qemu-devel@nongnu.org; Thu, 08 Sep 2011 01:33:59 -0400 Received: from mail-gw0-f52.google.com ([74.125.83.52]:57917) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R1XFN-0005NL-O0 for qemu-devel@nongnu.org; Thu, 08 Sep 2011 01:33:57 -0400 Received: by gwj15 with SMTP id 15so534834gwj.11 for ; Wed, 07 Sep 2011 22:33:56 -0700 (PDT) From: bharata.rao@gmail.com Date: Thu, 8 Sep 2011 11:03:28 +0530 Message-Id: <1315460008-22657-1-git-send-email-bharata.rao@gmail.com> Subject: [Qemu-devel] [PATCH v2] Fix X86 CPU topology in KVM mode List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: jan.kiszka@siemens.com, avi@redhat.com, Bharata B Rao From: Bharata B Rao 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. Signed-off-by: Bharata B Rao --- This is the next post of the fix that addresses Jan's comment about bringing back (smp_cpus > 1) check. The previous version was posted here: http://lists.gnu.org/archive/html/qemu-devel/2011-09/msg00892.html I coudn't boot a 486 kernel successfully with qemu and hence not sure if and how this fix breaks i486. Any help from Jan or others who might have easy means to boot 486 would be good. hw/pc.c | 1 - target-i386/helper.c | 5 +++++ 2 files changed, 5 insertions(+), 1 deletions(-) diff --git a/hw/pc.c b/hw/pc.c index 5bc845a..f9cca4d 100644 --- a/hw/pc.c +++ b/hw/pc.c @@ -933,7 +933,6 @@ 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 5df40d4..139a193 100644 --- a/target-i386/helper.c +++ b/target-i386/helper.c @@ -1256,6 +1256,11 @@ CPUX86State *cpu_x86_init(const char *cpu_model) cpu_x86_close(env); return NULL; } + + if ((env->cpuid_features & CPUID_APIC) || smp_cpus > 1) { + env->cpuid_apic_id = env->cpu_index; + } + mce_init(env); qemu_init_vcpu(env); -- 1.7.3.1