On Wed, Oct 17, 2018 at 12:48:58PM +0200, Paolo Bonzini wrote: > On 17/10/2018 11:30, Tao Xu wrote: > > As the release document ref below link (page 13): > > https://software.intel.com/sites/default/files/managed/c5/15/\ > > architecture-instruction-set-extensions-programming-reference.pdf > > > > PKU is supported in Skylake Server (Only Server) and later, and > > on Intel(R) Xeon(R) Processor Scalable Family. OSPKE is to reads > > the value of PKRU (Instruction of PKU) into EAX and clears EDX. > > So PKU/OSPKE are supposed to be in Skylake-Server CPU model. > > And PKU/OSPKE 's CPUID has been exposed to QEMU. But PKU/OSPKE > > can't be find in Skylake-Server CPU model in the code. > > So this patch will fix PKU/OSPKE this issue in Skylake-Server > > CPU model. > > OSPKE is not needed, since it is added automatically based on CR4 (and > is not set on boot).
Correct. > > Also, the guru of CPU model compatibility is Eduardo, so I'll wait for > him to chime in anyway. Sorry for taking so long to reply. This can be safely done only if every host that is able to run Skylake-Server today is guaranteed to support PKU. Is that the case? You'll also need Skylake-Server-*-cpu.pku=off entries on PC_COMPAT_3_0 to keep PKU disabled on pc-*-3.0 and older. -- Eduardo