Re: [PATCH v2 4/5] KVM: s390: vsie: Always test the crycbd for NULL

From: David Hildenbrand
Date: Wed Aug 22 2018 - 13:07:47 EST


On 22.08.2018 18:51, Pierre Morel wrote:
> BUG: the crycbd must be tested for null even if
> not crossing a page boundary (which will never
> occur in this case anyway).

I don't see the BUG. Can you elaborate? (maybe it is too late for me)

Either we return or we check for !crycb_addr

>
> Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> ---
> arch/s390/kvm/vsie.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
> index 0b12916..7ee4329 100644
> --- a/arch/s390/kvm/vsie.c
> +++ b/arch/s390/kvm/vsie.c
> @@ -172,7 +172,7 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
>
> if ((crycb_addr & PAGE_MASK) != ((crycb_addr + 128) & PAGE_MASK))
> return set_validity_icpt(scb_s, 0x003CU);
> - else if (!crycb_addr)
> + if (!crycb_addr)
> return set_validity_icpt(scb_s, 0x0039U);
>
> /* copy only the wrapping keys */
>


--

Thanks,

David / dhildenb