search for: 400000ffh

On Thu, Sep 18, 2014 at 9:36 AM, KY Srinivasan <kys at microsoft.com> wrote: > > I am copying other Hyper-V engineers to this discussion. > Thanks, K.Y. In terms of the address for the MSR, I suggest that you choose one from the range between 40000000H - 400000FFH. The SDM (35.1 ARCHITECTURAL MSRS) says "All existing and future processors will not implement any features using any MSR in this range." Hyper-V already defines many synthetic MSRs in this range, and I think it would be reasonable for you to pick one for this to avoid a conflict? -- Ju...

On Thu, Sep 18, 2014 at 9:36 AM, KY Srinivasan <kys at microsoft.com> wrote: > > I am copying other Hyper-V engineers to this discussion. > Thanks, K.Y. In terms of the address for the MSR, I suggest that you choose one from the range between 40000000H - 400000FFH. The SDM (35.1 ARCHITECTURAL MSRS) says "All existing and future processors will not implement any features using any MSR in this range." Hyper-V already defines many synthetic MSRs in this range, and I think it would be reasonable for you to pick one for this to avoid a conflict? -- Ju...

...on >>> Subject: Re: Standardizing an MSR or other hypercall to get an RNG seed? >>> >>> Il 18/09/2014 19:13, Nakajima, Jun ha scritto: >>> > In terms of the address for the MSR, I suggest that you choose one >>> > from the range between 40000000H - 400000FFH. The SDM (35.1 >>> > ARCHITECTURAL MSRS) says "All existing and future processors will not >>> > implement any features using any MSR in this range." Hyper-V already >>> > defines many synthetic MSRs in this range, and I think it would be >>> &...

...on >>> Subject: Re: Standardizing an MSR or other hypercall to get an RNG seed? >>> >>> Il 18/09/2014 19:13, Nakajima, Jun ha scritto: >>> > In terms of the address for the MSR, I suggest that you choose one >>> > from the range between 40000000H - 400000FFH. The SDM (35.1 >>> > ARCHITECTURAL MSRS) says "All existing and future processors will not >>> > implement any features using any MSR in this range." Hyper-V already >>> > defines many synthetic MSRs in this range, and I think it would be >>> &...

...n; Jake Oshins; Linux > Virtualization > Subject: Re: Standardizing an MSR or other hypercall to get an RNG seed? > > Il 18/09/2014 19:13, Nakajima, Jun ha scritto: > > In terms of the address for the MSR, I suggest that you choose one > > from the range between 40000000H - 400000FFH. The SDM (35.1 > > ARCHITECTURAL MSRS) says "All existing and future processors will not > > implement any features using any MSR in this range." Hyper-V already > > defines many synthetic MSRs in this range, and I think it would be > > reasonable for you to pick o...

...n; Jake Oshins; Linux > Virtualization > Subject: Re: Standardizing an MSR or other hypercall to get an RNG seed? > > Il 18/09/2014 19:13, Nakajima, Jun ha scritto: > > In terms of the address for the MSR, I suggest that you choose one > > from the range between 40000000H - 400000FFH. The SDM (35.1 > > ARCHITECTURAL MSRS) says "All existing and future processors will not > > implement any features using any MSR in this range." Hyper-V already > > defines many synthetic MSRs in this range, and I think it would be > > reasonable for you to pick o...

...pervisors and >> guests? That is, could we put something like "CrossHVPara\0" >> somewhere in that range, where each hypervisor would be free to decide >> exactly where it ends up? > > That's also possible, but extending the hypervisor CPUID range > beywond 400000FFH is not officially sanctioned by Intel. > > Xen started doing that in order to expose both Hyper-V and Xen > CPUID leaves, and KVM followed the practice. > Whoops. Might Intel be willing to extend that range to 0x40000000 - 0x400fffff? And would Microsoft be okay with using this mecha...

...pervisors and >> guests? That is, could we put something like "CrossHVPara\0" >> somewhere in that range, where each hypervisor would be free to decide >> exactly where it ends up? > > That's also possible, but extending the hypervisor CPUID range > beywond 400000FFH is not officially sanctioned by Intel. > > Xen started doing that in order to expose both Hyper-V and Xen > CPUID leaves, and KVM followed the practice. > Whoops. Might Intel be willing to extend that range to 0x40000000 - 0x400fffff? And would Microsoft be okay with using this mecha...

Il 18/09/2014 19:13, Nakajima, Jun ha scritto: > In terms of the address for the MSR, I suggest that you choose one > from the range between 40000000H - 400000FFH. The SDM (35.1 > ARCHITECTURAL MSRS) says "All existing and > future processors will not implement any features using any MSR in > this range." Hyper-V already defines many synthetic MSRs in this > range, and I think it would be reasonable for you to pick one for this > to...

...gt;> Virtualization >> Subject: Re: Standardizing an MSR or other hypercall to get an RNG seed? >> >> Il 18/09/2014 19:13, Nakajima, Jun ha scritto: >> > In terms of the address for the MSR, I suggest that you choose one >> > from the range between 40000000H - 400000FFH. The SDM (35.1 >> > ARCHITECTURAL MSRS) says "All existing and future processors will not >> > implement any features using any MSR in this range." Hyper-V already >> > defines many synthetic MSRs in this range, and I think it would be >> > reasonable f...

...nism to work across all hypervisors and > guests? That is, could we put something like "CrossHVPara\0" > somewhere in that range, where each hypervisor would be free to decide > exactly where it ends up? That's also possible, but extending the hypervisor CPUID range beywond 400000FFH is not officially sanctioned by Intel. Xen started doing that in order to expose both Hyper-V and Xen CPUID leaves, and KVM followed the practice. Paolo

...Re: Standardizing an MSR or other hypercall to get an RNG >seed? >>>> >>>> Il 18/09/2014 19:13, Nakajima, Jun ha scritto: >>>> > In terms of the address for the MSR, I suggest that you choose >one >>>> > from the range between 40000000H - 400000FFH. The SDM (35.1 >>>> > ARCHITECTURAL MSRS) says "All existing and future processors will >not >>>> > implement any features using any MSR in this range." Hyper-V >already >>>> > defines many synthetic MSRs in this range, and I think it wou...

On Thu, Sep 18, 2014 at 7:43 AM, H. Peter Anvin <hpa at zytor.com> wrote: > On 09/18/2014 07:40 AM, KY Srinivasan wrote: >>> >>> The main questions are what MSR index to use and how to detect the >>> presence of the MSR. I've played with two approaches: >>> >>> 1. Use CPUID to detect the presence of this feature. This is very easy for

On Thu, Sep 18, 2014 at 7:43 AM, H. Peter Anvin <hpa at zytor.com> wrote: > On 09/18/2014 07:40 AM, KY Srinivasan wrote: >>> >>> The main questions are what MSR index to use and how to detect the >>> presence of the MSR. I've played with two approaches: >>> >>> 1. Use CPUID to detect the presence of this feature. This is very easy for

...visors and >> guests? That is, could we put something like "CrossHVPara\0" >> somewhere in that range, where each hypervisor would be free to >> decide exactly where it ends up? > > That's also possible, but extending the hypervisor CPUID range beywond > 400000FFH is not officially sanctioned by Intel. > > Xen started doing that in order to expose both Hyper-V and Xen CPUID > leaves, and KVM followed the practice. > Whoops. Might Intel be willing to extend that range to 0x40000000 - 0x400fffff? And would Microsoft be okay with using this mech...

...visors and >> guests? That is, could we put something like "CrossHVPara\0" >> somewhere in that range, where each hypervisor would be free to >> decide exactly where it ends up? > > That's also possible, but extending the hypervisor CPUID range beywond > 400000FFH is not officially sanctioned by Intel. > > Xen started doing that in order to expose both Hyper-V and Xen CPUID > leaves, and KVM followed the practice. > Whoops. Might Intel be willing to extend that range to 0x40000000 - 0x400fffff? And would Microsoft be okay with using this mech...

...Re: Standardizing an MSR or other hypercall to get an RNG >seed? >>>> >>>> Il 18/09/2014 19:13, Nakajima, Jun ha scritto: >>>> > In terms of the address for the MSR, I suggest that you choose >one >>>> > from the range between 40000000H - 400000FFH. The SDM (35.1 >>>> > ARCHITECTURAL MSRS) says "All existing and future processors will >not >>>> > implement any features using any MSR in this range." Hyper-V >already >>>> > defines many synthetic MSRs in this range, and I think it wo...

...Re: Standardizing an MSR or other hypercall to get an RNG >seed? >>>> >>>> Il 18/09/2014 19:13, Nakajima, Jun ha scritto: >>>> > In terms of the address for the MSR, I suggest that you choose >one >>>> > from the range between 40000000H - 400000FFH. The SDM (35.1 >>>> > ARCHITECTURAL MSRS) says "All existing and future processors will >not >>>> > implement any features using any MSR in this range." Hyper-V >already >>>> > defines many synthetic MSRs in this range, and I think it wo...