Re: qemu-kvm: enable get/set vcpu events on reset and migration

[Jan Kiszka <jan.kiszka@siemens.com>]

Marcelo Tosatti wrote:
> qemu-kvm should reset and save/restore vcpu events.
> 
> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
> 
> diff --git a/kvm.h b/kvm.h
> index e2a945b..9fa4e25 100644
> --- a/kvm.h
> +++ b/kvm.h
> @@ -52,6 +52,9 @@ int kvm_set_migration_log(int enable);
>  int kvm_has_sync_mmu(void);
>  #endif /* KVM_UPSTREAM */
>  int kvm_has_vcpu_events(void);
> +int kvm_put_vcpu_events(CPUState *env);
> +int kvm_get_vcpu_events(CPUState *env);
> +
>  #ifdef KVM_UPSTREAM
>  
>  void kvm_setup_guest_memory(void *start, size_t size);
> @@ -96,7 +99,9 @@ int kvm_arch_init(KVMState *s, int smp_cpus);
>  
>  int kvm_arch_init_vcpu(CPUState *env);
>  
> +#endif
>  void kvm_arch_reset_vcpu(CPUState *env);
> +#ifdef KVM_UPSTREAM
>  
>  struct kvm_guest_debug;
>  struct kvm_debug_exit_arch;
> diff --git a/qemu-kvm-x86.c b/qemu-kvm-x86.c
> index 82e362c..7f820a4 100644
> --- a/qemu-kvm-x86.c
> +++ b/qemu-kvm-x86.c
> @@ -1457,8 +1457,9 @@ void kvm_arch_push_nmi(void *opaque)
>  
>  void kvm_arch_cpu_reset(CPUState *env)
>  {
> -    env->interrupt_injected = -1;
> +    kvm_arch_reset_vcpu(env);
>      kvm_arch_load_regs(env);
> +    kvm_put_vcpu_events(env);
>      if (!cpu_is_bsp(env)) {
>  	if (kvm_irqchip_in_kernel()) {
>  #ifdef KVM_CAP_MP_STATE
> diff --git a/qemu-kvm.c b/qemu-kvm.c
> index 1c34846..f891a3e 100644
> --- a/qemu-kvm.c
> +++ b/qemu-kvm.c
> @@ -2187,6 +2187,11 @@ static int kvm_create_context(void)
>          return r;
>      }
>  
> +    kvm_state->vcpu_events = 0;
> +#ifdef KVM_CAP_VCPU_EVENTS
> +    kvm_state->vcpu_events = kvm_check_extension(kvm_state, KVM_CAP_VCPU_EVENTS);
> +#endif
> +
>      kvm_init_ap();
>      if (kvm_irqchip) {
>          if (!qemu_kvm_has_gsi_routing()) {
> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index 9af1e48..79be2d5 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -285,6 +285,7 @@ int kvm_arch_init_vcpu(CPUState *env)
>      return kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
>  }
>  
> +#endif
>  void kvm_arch_reset_vcpu(CPUState *env)
>  {
>      env->exception_injected = -1;
> @@ -292,6 +293,7 @@ void kvm_arch_reset_vcpu(CPUState *env)
>      env->nmi_injected = 0;
>      env->nmi_pending = 0;
>  }
> +#ifdef KVM_UPSTREAM
>  
>  static int kvm_has_msr_star(CPUState *env)
>  {
> @@ -776,8 +778,9 @@ static int kvm_get_mp_state(CPUState *env)
>      env->mp_state = mp_state.mp_state;
>      return 0;
>  }
> +#endif
>  
> -static int kvm_put_vcpu_events(CPUState *env)
> +int kvm_put_vcpu_events(CPUState *env)
>  {
>  #ifdef KVM_CAP_VCPU_EVENTS
>      struct kvm_vcpu_events events;
> @@ -807,7 +810,7 @@ static int kvm_put_vcpu_events(CPUState *env)
>  #endif
>  }
>  
> -static int kvm_get_vcpu_events(CPUState *env)
> +int kvm_get_vcpu_events(CPUState *env)
>  {
>  #ifdef KVM_CAP_VCPU_EVENTS
>      struct kvm_vcpu_events events;
> @@ -844,6 +847,7 @@ static int kvm_get_vcpu_events(CPUState *env)
>      return 0;
>  }
>  
> +#ifdef KVM_UPSTREAM
>  int kvm_arch_put_registers(CPUState *env)
>  {
>      int ret;
> diff --git a/target-i386/machine.c b/target-i386/machine.c
> index 47ca6e8..219224d 100644
> --- a/target-i386/machine.c
> +++ b/target-i386/machine.c
> @@ -324,6 +324,7 @@ static void cpu_pre_save(void *opaque)
>  
>      cpu_synchronize_state(env);
>      kvm_save_mpstate(env);
> +    kvm_get_vcpu_events(env);
>  
>      /* FPU */
>      env->fpus_vmstate = (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
> @@ -374,6 +375,7 @@ static int cpu_post_load(void *opaque, int version_id)
>  
>          kvm_load_tsc(env);
>          kvm_load_mpstate(env);
> +        kvm_put_vcpu_events(env);

The last two hunks will cause the same !CONFIG_KVM breakages qemu-kvm's
mpstate used to as well. You may either fix it up temporarily or wait
for my refactoring that is now scheduled with highest priority (should
be ready today or tomorrow).

Jan

-- 
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