Re: [PATCH 1/2] KVM: async_pf: Cleanup kvm_setup_async_pf()

[Paolo Bonzini]

On 10/06/20 20:14, Sean Christopherson wrote:
>> -	/* setup delayed work */
>> +	/* Arch specific code should not do async PF in this case */
>> +	if (unlikely(kvm_is_error_hva(hva)))
> This feels like it should be changed to a WARN_ON_ONCE in a follow-up.
> With the WARN, the comment could probably be dropped.

I think a race is possible in principle where the memslots are changed
(for example) between s390's page fault handler and the gfn_to_hva call
in kvm_arch_setup_async_pf.

Queued both, thanks!

Paolo