Re: [Qemu-devel] [PATCH] KVM: emulate lapic tsc deadline timer for hvm

[Avi Kivity]

On 09/07/2011 07:45 PM, Liu, Jinsong wrote:
> Avi Kivity wrote:
> >>
> >>  --- a/arch/x86/include/asm/msr-index.h
> >>  +++ b/arch/x86/include/asm/msr-index.h
> >>  @@ -229,6 +229,8 @@
> >>    #define MSR_IA32_APICBASE_ENABLE    (1<<11)
> >>    #define MSR_IA32_APICBASE_BASE              (0xfffff<<12)
> >>
> >>  +#define MSR_IA32_TSCDEADLINE         0x000006e0
> >>  +
> >>    #define MSR_IA32_UCODE_WRITE                0x00000079
> >>    #define MSR_IA32_UCODE_REV          0x0000008b
> >>
> >
> >  Need to add to msrs_to_save so live migration works.
> >
>
> 2 questions:
> 1). how about add to emulated_msrs instead of msrs_to_save? msrs_to_save 
> modified at runtime and depend on capacibility of host cpu.

Look at kvm_init_msrs_list(), it does the checks.

> 2). do we need add code at qemu (kvm_get_msrs/ kvm_put_msrs) to expose 
> MSR_IA32_TSCDEADLINE to userspace?

It should be automatic.  Better check it though that you can 
live-migrate a guest that uses TSC deadline.  Please add a testcase to 
kvm-unit-tests.git (there's x86/apic.c, can probably be added there easily).

--
error compiling committee.c: too many arguments to function