From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:37392) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R1HjY-0002qM-Gl for qemu-devel@nongnu.org; Wed, 07 Sep 2011 09:00:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1R1HjR-0007vV-NR for qemu-devel@nongnu.org; Wed, 07 Sep 2011 09:00:04 -0400 Received: from mail-yx0-f173.google.com ([209.85.213.173]:46351) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R1HjR-0007vN-HU for qemu-devel@nongnu.org; Wed, 07 Sep 2011 08:59:57 -0400 Received: by yxt3 with SMTP id 3so4377237yxt.4 for ; Wed, 07 Sep 2011 05:59:56 -0700 (PDT) Message-ID: <4E676AC7.7030405@codemonkey.ws> Date: Wed, 07 Sep 2011 07:59:51 -0500 From: Anthony Liguori MIME-Version: 1.0 References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [FIX] X86 CPU topology broken in KVM mode List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Bharata B Rao Cc: Jan Kiszka , qemu-devel@nongnu.org, Avi Kivity On 09/06/2011 11:21 PM, Bharata B Rao wrote: > Hi, > > Sometime back I posted a patch for fixing x86 CPU topology ( > http://lists.gnu.org/archive/html/qemu-devel/2011-08/msg02022.html). > Here is the next version of the fix which addresses all but one > comment received during that post. > > - Fixed code style issues > - Ensured that the fix doesn't break TCG mode > - I am not sure what is the problem with i486 as I haven't been able > to boot an i486 VM successfully, hence haven't attempted to fix this. > > I have tested following scenarios and found the fix to be working fine. > > KVM: (with --enable-kvm) > -smp sockets=1,cores=4,threads=2 > -smp sockets=4,cores=4,threads=2 > -cpu core2duo sockets=1,cores=4,threads=2 > -cpu core2duo sockets=2,cores=4,threads=2 > > TCG: (without --enable-kvm) > -cpu core2duo sockets=1,cores=4,threads=2 > -cpu core2duo sockets=2,cores=4,threads=2 > > Here is the updated patch which now applies against qemu.git. > > ******************** > Fix apic id enumeration > > 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. > > 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 Please post patches as top-level threads with [PATCH] in the subject. Please use git diff or better yet, git-send-email. Regards, Anthony Liguori > --- > hw/pc.c | 1 - > target-i386/helper.c | 5 +++++ > 2 files changed, 5 insertions(+), 1 deletion(-) > > Index: qemu/hw/pc.c > =================================================================== > --- qemu.orig/hw/pc.c > +++ qemu/hw/pc.c > @@ -933,7 +933,6 @@ static CPUState *pc_new_cpu(const char * > 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); > Index: qemu/target-i386/helper.c > =================================================================== > --- qemu.orig/target-i386/helper.c > +++ qemu/target-i386/helper.c > @@ -1256,6 +1256,11 @@ CPUX86State *cpu_x86_init(const char *cp > cpu_x86_close(env); > return NULL; > } > + > + if (env->cpuid_features& CPUID_APIC) { > + env->cpuid_apic_id = env->cpu_index; > + } > + > mce_init(env); > > qemu_init_vcpu(env); > ************************* > > Regards, > Bharata. > -- > http://bharata.sulekha.com/blog/posts.htm, http://raobharata.wordpress.com/ >