From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [uq/master PATCH] kvm: i386: fix LAPIC TSC deadline timer save/restore
Date: Mon, 19 Aug 2013 20:57:58 +0200
Message-ID: <52126AB6.20005@redhat.com>
References: <20130819171342.GA3272@amt.cnet>
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Cc: kvm-devel <kvm@vger.kernel.org>, Gleb Natapov <gleb@redhat.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
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Il 19/08/2013 19:13, Marcelo Tosatti ha scritto:
> 
> The configuration of the timer represented by MSR_IA32_TSCDEADLINE depends on:
> 
> - APIC LVT Timer register.
> - TSC value.
> 
> Change the order to respect the dependency.

Do you have a testcase?

Paolo

> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
> 
> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index 376fc70..d04c6ae 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -1044,6 +1044,26 @@ static void kvm_msr_entry_set(struct kvm_msr_entry *entry,
>      entry->data = value;
>  }
>  
> +static int kvm_put_tscdeadline_msr(X86CPU *cpu)
> +{
> +    CPUX86State *env = &cpu->env;
> +    struct {
> +        struct kvm_msrs info;
> +        struct kvm_msr_entry entries[1];
> +    } msr_data;
> +    struct kvm_msr_entry *msrs = msr_data.entries;
> +
> +    if (!has_msr_tsc_deadline) {
> +        return 0;
> +    }
> +
> +    kvm_msr_entry_set(&msrs[0], MSR_IA32_TSCDEADLINE, env->tsc_deadline);
> +
> +    msr_data.info.nmsrs = 1;
> +
> +    return kvm_vcpu_ioctl(CPU(cpu), KVM_SET_MSRS, &msr_data);
> +}
> +
>  static int kvm_put_msrs(X86CPU *cpu, int level)
>  {
>      CPUX86State *env = &cpu->env;
> @@ -1067,9 +1087,6 @@ static int kvm_put_msrs(X86CPU *cpu, int level)
>      if (has_msr_tsc_adjust) {
>          kvm_msr_entry_set(&msrs[n++], MSR_TSC_ADJUST, env->tsc_adjust);
>      }
> -    if (has_msr_tsc_deadline) {
> -        kvm_msr_entry_set(&msrs[n++], MSR_IA32_TSCDEADLINE, env->tsc_deadline);
> -    }
>      if (has_msr_misc_enable) {
>          kvm_msr_entry_set(&msrs[n++], MSR_IA32_MISC_ENABLE,
>                            env->msr_ia32_misc_enable);
> @@ -1708,6 +1725,12 @@ int kvm_arch_put_registers(CPUState *cpu, int level)
>              return ret;
>          }
>      }
> +
> +    ret = kvm_put_tscdeadline_msr(x86_cpu);
> +    if (ret < 0) {
> +        return ret;
> +    }
> +
>      ret = kvm_put_vcpu_events(x86_cpu, level);
>      if (ret < 0) {
>          return ret;
>