[Xen-devel] [PATCH 4/9] x86/amd: Introduce CPUID/MSR definitions for per-vcpu SSBD support

2018-12-03 Thread Andrew Cooper
At the time of writing, the spec is available from: https://developer.amd.com/wp-content/resources/124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf Future hardware (Zen v2) is expect to have hardware MSR_SPEC_CTRL support, including SPEC_CTRL.SSBD, and with the expectation that

Re: [Xen-devel] [PATCH 4/9] x86/amd: Introduce CPUID/MSR definitions for per-vcpu SSBD support

2018-12-04 Thread Woods, Brian
On Mon, Dec 03, 2018 at 04:18:17PM +, Andy Cooper wrote: > At the time of writing, the spec is available from: > > > https://developer.amd.com/wp-content/resources/124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf > > Future hardware (Zen v2) is expect to have hardware MSR_SP

Re: [Xen-devel] [PATCH 4/9] x86/amd: Introduce CPUID/MSR definitions for per-vcpu SSBD support

2018-12-05 Thread Jan Beulich
>>> On 03.12.18 at 17:18, wrote: > At the time of writing, the spec is available from: > > > https://developer.amd.com/wp-content/resources/124441_AMD64_SpeculativeStoreB > ypassDisable_Whitepaper_final.pdf > > Future hardware (Zen v2) is expect to have hardware MSR_SPEC_CTRL support, > incl

Re: [Xen-devel] [PATCH 4/9] x86/amd: Introduce CPUID/MSR definitions for per-vcpu SSBD support

2018-12-05 Thread Andrew Cooper
On 05/12/2018 16:39, Jan Beulich wrote: On 03.12.18 at 17:18, wrote: >> At the time of writing, the spec is available from: >> >> >> https://developer.amd.com/wp-content/resources/124441_AMD64_SpeculativeStoreB >> >> ypassDisable_Whitepaper_final.pdf >> >> Future hardware (Zen v2) is exp

Re: [Xen-devel] [PATCH 4/9] x86/amd: Introduce CPUID/MSR definitions for per-vcpu SSBD support

2018-12-06 Thread Jan Beulich
>>> On 05.12.18 at 18:50, wrote: > On 05/12/2018 16:39, Jan Beulich wrote: > On 03.12.18 at 17:18, wrote: >>> As an alternative, MSR_VIRT_SPEC_CTRL is specified as an architectural >>> control >>> (with semantics equivilent to MSR_SPEC_CTRL) which is provided by the >>> hypervisor. This abs

Re: [Xen-devel] [PATCH 4/9] x86/amd: Introduce CPUID/MSR definitions for per-vcpu SSBD support

2018-12-06 Thread Andrew Cooper
On 06/12/2018 08:49, Jan Beulich wrote: +{"amd_stibp",0x8008, NA, CPUID_REG_EBX, 15, 1}, +{"amd_ssbd", 0x8008, NA, CPUID_REG_EBX, 24, 1}, +{"virt_sc_ssbd", 0x8008, NA, CPUID_REG_EBX, 25, 1}, +{"amd_ssb_no", 0x8008, NA,