Re: [PATCH v4 18/36] KVM: S390: protvirt: Introduce instruction data area bounce buffer

Christian Borntraeger
2020-02-25T18:39:38Z

On 25.02.20 18:21, Cornelia Huck wrote:
> On Tue, 25 Feb 2020 08:50:47 +0100
> Christian Borntraeger <borntraeger@de.ibm.com> wrote:
>
>> This is the guest breaking event address. So a guest (and QEMU) can read it.
>> It is kind of overlaid sida and gbea. Something like this:
>>
>> diff --git a/arch/s390/kvm/pv.c b/arch/s390/kvm/pv.c
>> index cd81a58349a9..055bf0ec8fbb 100644
>> --- a/arch/s390/kvm/pv.c
>> +++ b/arch/s390/kvm/pv.c
>> @@ -39,6 +39,11 @@ int kvm_s390_pv_destroy_cpu(struct kvm_vcpu *vcpu, u16 *rc, u16 *rrc)
>> vcpu->arch.sie_block->pv_handle_config = 0;
>> memset(&vcpu->arch.pv, 0, sizeof(vcpu->arch.pv));
>> vcpu->arch.sie_block->sdf = 0;
>> + /*
>> + * the sidad field (for sdf == 2) is now the gbea field (for sdf == 0).
>
> s/the sidad/The sidad/

ack
>
>> + * Use the reset value of gbea to not leak the kernel pointer of the
>
> s/to not leak/to avoid leaking/

>
>> + * just free sida
>
> s/free sida/freed sida./

ack

>