On 14.02.20 23:26, Christian Borntraeger wrote:
> From: Janosch Frank <frankja@xxxxxxxxxxxxx>
>
> Save response to sidad and disable address checking for protected
> guests.
>
> Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
> Reviewed-by: Thomas Huth <thuth@xxxxxxxxxx>
> Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>
> [borntraeger@xxxxxxxxxx: patch merging, splitting, fixing]
> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
> ---
> arch/s390/kvm/priv.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
> index ed52ffa8d5d4..b2de7dc5f58d 100644
> --- a/arch/s390/kvm/priv.c
> +++ b/arch/s390/kvm/priv.c
> @@ -872,7 +872,7 @@ static int handle_stsi(struct kvm_vcpu *vcpu)
>
> operand2 = kvm_s390_get_base_disp_s(vcpu, &ar);
>
> - if (operand2 & 0xfff)
> + if (!kvm_s390_pv_is_protected(vcpu->kvm) && (operand2 & 0xfff))
> return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
Why is that needed? I'd assume the hardware handles this for us and this
case can never happen for PV? (IOW, change is not necessary)
>
> switch (fc) {
> @@ -893,8 +893,13 @@ static int handle_stsi(struct kvm_vcpu *vcpu)
> handle_stsi_3_2_2(vcpu, (void *) mem);
> break;
> }
> -
> - rc = write_guest(vcpu, operand2, ar, (void *)mem, PAGE_SIZE);
> + if (kvm_s390_pv_is_protected(vcpu->kvm)) {
> + memcpy((void *)sida_origin(vcpu->arch.sie_block), (void *)mem,
> + PAGE_SIZE);
> + rc = 0;
> + } else {
> + rc = write_guest(vcpu, operand2, ar, (void *)mem, PAGE_SIZE);
> + }
> if (rc) {
> rc = kvm_s390_inject_prog_cond(vcpu, rc);
> goto out;
>
I'd pull the interrupt injection into the else case, makes things clearer.
What about user_stsi? Will that still work? (I assume user space will
write to the sida and it should work just fine)
(I assume races regarding kvm_s390_pv_is_protected() will be dealt with
in your next series)
In general, looks good to me.
--
Thanks,
David / dhildenb
