Reviewed-by: Bibo, Mao <maobibo@xxxxxxxxxxx>
在 2023/5/30 09:52, Tianrui Zhao 写道:
> Implement handle fpu exception, using kvm_own_fpu to enable fpu for
> guest.
>
> Signed-off-by: Tianrui Zhao <zhaotianrui@xxxxxxxxxxx>
> ---
> arch/loongarch/kvm/exit.c | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)
>
> diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c
> index 1237ceb06d0c..10f9922a7e76 100644
> --- a/arch/loongarch/kvm/exit.c
> +++ b/arch/loongarch/kvm/exit.c
> @@ -631,3 +631,29 @@ static int _kvm_handle_read_fault(struct kvm_vcpu *vcpu)
> {
> return _kvm_handle_mmu_fault(vcpu, false);
> }
> +
> +/**
> + * _kvm_handle_fpu_disabled() - Guest used fpu however it is disabled at host
> + * @vcpu: Virtual CPU context.
> + *
> + * Handle when the guest attempts to use fpu which hasn't been allowed
> + * by the root context.
> + */
> +static int _kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu)
> +{
> + struct kvm_run *run = vcpu->run;
> +
> + /*
> + * If guest FPU not present, the FPU operation should have been
> + * treated as a reserved instruction!
> + * If FPU already in use, we shouldn't get this at all.
> + */
> + if (WARN_ON(vcpu->arch.aux_inuse & KVM_LARCH_FPU)) {
> + kvm_err("%s internal error\n", __func__);
> + run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
> + return RESUME_HOST;
> + }
> +
> + kvm_own_fpu(vcpu);
> + return RESUME_GUEST;
> +}
