> -----Original Message----- > From: Gleb Natapov [mailto:gleb@xxxxxxxxxx] > Sent: Thursday, April 18, 2013 7:08 PM > To: Ren, Yongjie > Cc: Marcelo Tosatti; kvm@xxxxxxxxxxxxxxx; qemu-devel@xxxxxxxxxx; > ehabkost@xxxxxxxxxx > Subject: Re: [PATCH] target-i386: upgrade family number of qemu64 CPU > model to 15 > > On Thu, Apr 18, 2013 at 10:45:38AM +0000, Ren, Yongjie wrote: > > qemu64 is the default CPU model for QEMU/KVM on x86-64, but its > family number > > definition is not accurate. The vendor of 'qemu64' is defined as 'AMD'. > For AMD > > processors, AMD K8 (i.e. Family 15) firstly introduced SSE3 instruction > set. > > 'qemu64' already has 'CPUID_EXT_SSE3' in its ext_features, but its family > > number is only 6 which is not equal to or greater than 15. > > So, upgrade the CPU family number of qemu64 model to 15. > > After this upgrade, 32bit Windows 8 can boot up with qemu64 CPU > model. > > This upgrade can be also a fix to the below bug about 32bit Windows 8 > booting. > > https://bugs.launchpad.net/qemu/+bug/1007269 > > Changing cpuid info is not that simple since this is guest visible > information and can impact migration. Old machine models should still > expose the old family. > Sorry, I didn't consider migration issue. I just think the cupid info for qemu64 is not compatible with real-world CPU. Family 6 AMD CPU should not have SSE3 but it has SSE3 in qemu64 model. If it's not so simple to modify cupid info, just ignore my patch. :-) > > > > Signed-off-by: Yongjie Ren <yongjie.ren@xxxxxxxxx> > > --- > > target-i386/cpu.c | 2 +- > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > diff --git a/target-i386/cpu.c b/target-i386/cpu.c > > index e2302d8..3f8e6c3 100644 > > --- a/target-i386/cpu.c > > +++ b/target-i386/cpu.c > > @@ -420,7 +420,7 @@ static x86_def_t builtin_x86_defs[] = { > > .name = "qemu64", > > .level = 4, > > .vendor = CPUID_VENDOR_AMD, > > - .family = 6, > > + .family = 15, > > .model = 2, > > .stepping = 3, > > .features = PPRO_FEATURES | > > -- > > 1.7.1 > > -- > Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
