Re: [PATCH] kvm_para_available() should check hypervisor bit before accessing hypervisor cpuid leaf.
|[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]|
On Tue, May 01, 2012 at 03:59:33PM +0300, Avi Kivity wrote: > On 05/01/2012 03:55 PM, Gleb Natapov wrote: > > On Tue, May 01, 2012 at 03:50:44PM +0300, Avi Kivity wrote: > > > On 04/30/2012 02:45 PM, Gleb Natapov wrote: > > > > This couid range does not exist on real HW and Intel spec says that > > > > "Information returned for highest basic information leaf" will be > > > > returned. Not very well defined. > > > > > > > > > > Correct in principle. But IIRC some old qemus supported the kvm cpuid > > > range without setting the hypervisor bit. > > > > > How old? > > commit e19967a0e00c7af4efd2f2db12a7d5d7f0b387f7 > Author: Avi Kivity <avi@xxxxxxxxxxxx> > Date: Tue Apr 22 11:44:19 2008 +0300 > > Set "hypervisor present" cpuid bit > > This tells Microsoft guests that they are running under a hypervisor. > > Signed-off-by: Avi Kivity <avi@xxxxxxxxxxxx > > $ git describe --contains e19967a0e00c > kvm-80rc2~489 > Since latest Windowses will not run on such old version correctly (may use tsc for QPC) may be dropping support for Linuxes past 3.4 is a possibility too? -- 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