Re: [PATCH] KVM: s390: vsie: BUG correction by shadow_crycb

From: David Hildenbrand
Date: Tue Aug 21 2018 - 10:35:09 EST


On 21.08.2018 16:19, Pierre Morel wrote:
> Copy the key mask to the right offset inside the shadow CRYCB

"KVM: s390: vsie: copy wrapping keys to right place"

Indeed, we're writing it into the apcb0 mask (which is ignored).
Luckily, the xor-ing with the g2 keys seems to work.

Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>

>
> Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> ---
> arch/s390/kvm/vsie.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
> index 63844b9..a2b28cd 100644
> --- a/arch/s390/kvm/vsie.c
> +++ b/arch/s390/kvm/vsie.c
> @@ -173,7 +173,8 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
> return set_validity_icpt(scb_s, 0x0039U);
>
> /* copy only the wrapping keys */
> - if (read_guest_real(vcpu, crycb_addr + 72, &vsie_page->crycb, 56))
> + if (read_guest_real(vcpu, crycb_addr + 72,
> + vsie_page->crycb.dea_wrapping_key_mask, 56))
> return set_validity_icpt(scb_s, 0x0035U);
>
> scb_s->ecb3 |= ecb3_flags;
>


--

Thanks,

David / dhildenb