> -----Original Message----- > From: Jan Beulich [mailto:JBeulich@xxxxxxxx] > Sent: Thursday, January 31, 2013 2:38 AM > To: KY Srinivasan > Cc: olaf@xxxxxxxxx; bp@xxxxxxxxx; apw@xxxxxxxxxxxxx; x86@xxxxxxxxxx; > tglx@xxxxxxxxxxxxx; devel@xxxxxxxxxxxxxxxxxxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; > jasowang@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; hpa@xxxxxxxxx > Subject: RE: [PATCH 2/3] X86: Add a check to catch Xen emulation of Hyper-V > > >>> On 30.01.13 at 19:12, KY Srinivasan <kys@xxxxxxxxxxxxx> wrote: > > Presumably, Hyper-V emulation is only to run enlightened Windows. The issue > > with > > Xen is not that it emulates Hyper-V, but this emulation is turned on while > > running Linux. > > That is the reason I chose to check for Xen. Would you prefer a DMI check > > for the Hyper-V > > platform. > > I consider DMI checks to be too fragile here - in particular with > the eventual passing through of host DMI attributes to guests, > this sets you up for mistakes. Instead, I would envision you > scanning the whole CPUID range "reserved" for virtualization > (starting at 0x40000000) and see whether you get back > anything other than the Hyper-V identification (much like the > way xen_cpuid_base() scans for the Xen range). Of course > that's under the premise that you're right in assuming Hyper-V > would never emulate any other hypervisor's interface. Agreed; I will make the appropriate changes as you have recommended. Regards, K. Y _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
