Re: [PATCH v5 12/12] Send async PF when guest is not in userspace too.

Avi Kivity
2010-08-24T09:37:11Z

On 07/19/2010 06:31 PM, Gleb Natapov wrote:
> If guest indicates that it can handle async pf in kernel mode too send
> it, but only if interrupt are enabled.
>
> Reviewed-by: Rik van Riel<riel@redhat.com>
> Signed-off-by: Gleb Natapov<gleb@redhat.com>
> ---
> arch/x86/kvm/mmu.c | 8 +++++++-
> 1 files changed, 7 insertions(+), 1 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
> index 12d1a7b..ed87b1c 100644
> --- a/arch/x86/kvm/mmu.c
> +++ b/arch/x86/kvm/mmu.c
> @@ -2361,7 +2361,13 @@ static bool can_do_async_pf(struct kvm_vcpu *vcpu)
> if (!vcpu->arch.apf_data || kvm_event_needs_reinjection(vcpu))
> return false;
>
> - return !!kvm_x86_ops->get_cpl(vcpu);
> + if (vcpu->arch.apf_send_user_only)
> + return !!kvm_x86_ops->get_cpl(vcpu);

cpl is not a bool. Compare it with 0.

> +
> + if (!kvm_x86_ops->interrupt_allowed(vcpu))
> + return false;
> +
> + return true;
> }

Should have commented before, but get_cpl() is not accurate when doing
nested virtualization. When L1 intercepts page faults, being in L2 is
equivalent to CPL 3. But we need to get the apf information to L1 somehow.

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