Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-19 Thread Paolo Bonzini
On 19/02/2018 14:35, David Woodhouse wrote: > On Mon, 2018-02-19 at 14:10 +0100, Paolo Bonzini wrote: >>> Hardware seems like a reasonable place to get the default value (cf. >>> the VMX capability MSRs). >> >> There are some differences: >> >> - a zero value for ARCH_CAPABILITIES should be safe,

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-19 Thread Paolo Bonzini
On 19/02/2018 14:35, David Woodhouse wrote: > On Mon, 2018-02-19 at 14:10 +0100, Paolo Bonzini wrote: >>> Hardware seems like a reasonable place to get the default value (cf. >>> the VMX capability MSRs). >> >> There are some differences: >> >> - a zero value for ARCH_CAPABILITIES should be safe,

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-19 Thread David Woodhouse
On Mon, 2018-02-19 at 14:10 +0100, Paolo Bonzini wrote: > > Hardware seems like a reasonable place to get the default value (cf. > > the VMX capability MSRs). > > There are some differences: > > - a zero value for ARCH_CAPABILITIES should be safe, while a zero value > for VMX capabilities

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-19 Thread David Woodhouse
On Mon, 2018-02-19 at 14:10 +0100, Paolo Bonzini wrote: > > Hardware seems like a reasonable place to get the default value (cf. > > the VMX capability MSRs). > > There are some differences: > > - a zero value for ARCH_CAPABILITIES should be safe, while a zero value > for VMX capabilities

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-19 Thread Paolo Bonzini
On 16/02/2018 17:29, Jim Mattson wrote: > On Fri, Feb 16, 2018 at 6:18 AM, Paolo Bonzini wrote: > >> Uhm, taking contents from the hardware is wrong (guess why---live >> migration). I'll send a revert of those two lines. > > Hardware seems like a reasonable place to get

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-19 Thread Paolo Bonzini
On 16/02/2018 17:29, Jim Mattson wrote: > On Fri, Feb 16, 2018 at 6:18 AM, Paolo Bonzini wrote: > >> Uhm, taking contents from the hardware is wrong (guess why---live >> migration). I'll send a revert of those two lines. > > Hardware seems like a reasonable place to get the default value (cf.

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-16 Thread David Woodhouse
On Fri, 2018-02-16 at 08:29 -0800, Jim Mattson wrote: > On Fri, Feb 16, 2018 at 6:18 AM, Paolo Bonzini wrote: > > > Uhm, taking contents from the hardware is wrong (guess why---live > > migration).  I'll send a revert of those two lines. > > Hardware seems like a

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-16 Thread David Woodhouse
On Fri, 2018-02-16 at 08:29 -0800, Jim Mattson wrote: > On Fri, Feb 16, 2018 at 6:18 AM, Paolo Bonzini wrote: > > > Uhm, taking contents from the hardware is wrong (guess why---live > > migration).  I'll send a revert of those two lines. > > Hardware seems like a reasonable place to get the

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-16 Thread Jim Mattson
On Fri, Feb 16, 2018 at 6:18 AM, Paolo Bonzini wrote: > Uhm, taking contents from the hardware is wrong (guess why---live > migration). I'll send a revert of those two lines. Hardware seems like a reasonable place to get the default value (cf. the VMX capability MSRs).

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-16 Thread Jim Mattson
On Fri, Feb 16, 2018 at 6:18 AM, Paolo Bonzini wrote: > Uhm, taking contents from the hardware is wrong (guess why---live > migration). I'll send a revert of those two lines. Hardware seems like a reasonable place to get the default value (cf. the VMX capability MSRs). Should these two lines

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-16 Thread Paolo Bonzini
On 06/02/2018 18:29, David Woodhouse wrote: > From: KarimAllah Ahmed > > Intel processors use MSR_IA32_ARCH_CAPABILITIES MSR to indicate RDCL_NO > (bit 0) and IBRS_ALL (bit 1). This is a read-only MSR. By default the > contents will come directly from the hardware, but

Re: [PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-16 Thread Paolo Bonzini
On 06/02/2018 18:29, David Woodhouse wrote: > From: KarimAllah Ahmed > > Intel processors use MSR_IA32_ARCH_CAPABILITIES MSR to indicate RDCL_NO > (bit 0) and IBRS_ALL (bit 1). This is a read-only MSR. By default the > contents will come directly from the hardware, but user-space can still >

[PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-06 Thread David Woodhouse
From: KarimAllah Ahmed Intel processors use MSR_IA32_ARCH_CAPABILITIES MSR to indicate RDCL_NO (bit 0) and IBRS_ALL (bit 1). This is a read-only MSR. By default the contents will come directly from the hardware, but user-space can still override it. [dwmw2: The bit in

[PATCH 7/9] KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES

2018-02-06 Thread David Woodhouse
From: KarimAllah Ahmed Intel processors use MSR_IA32_ARCH_CAPABILITIES MSR to indicate RDCL_NO (bit 0) and IBRS_ALL (bit 1). This is a read-only MSR. By default the contents will come directly from the hardware, but user-space can still override it. [dwmw2: The bit in