On 15.02.2018 16:43, Janosch Frank wrote:
> Up to now we always expected to have the storage key facility
> available for our (non-VSIE) KVM guests. For huge page support, we
> need to be able to disable it, so let's introduce that now.
>
> Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxxxxxxx>
> ---
> arch/s390/include/asm/kvm_host.h | 1 +
> arch/s390/kvm/kvm-s390.c | 1 +
> arch/s390/kvm/priv.c | 22 +++++++++++++---------
> 3 files changed, 15 insertions(+), 9 deletions(-)
>
> diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
> index b768754..ccbbd12 100644
> --- a/arch/s390/include/asm/kvm_host.h
> +++ b/arch/s390/include/asm/kvm_host.h
> @@ -793,6 +793,7 @@ struct kvm_arch{
> int use_irqchip;
> int has_cmma;
> int has_pfmfi;
> + int has_skf;
> int user_cpu_state_ctrl;
> int user_sigp;
> int user_stsi;
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 781aaf0..ddf3599 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -2010,6 +2010,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
> kvm->arch.css_support = 0;
> kvm->arch.use_irqchip = 0;
> kvm->arch.has_pfmfi = sclp.has_pfmfi;
> + kvm->arch.has_skf = sclp.has_skey;
Dito has_skf rather relates to a vSIE feature for the guest ("this guest
has the SKF, therefore can use it for the (v)SIE").
-> use_skf IMHO.
> kvm->arch.epoch = 0;
>
> spin_lock_init(&kvm->arch.start_stop_lock);
> diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
> index 908b579..c74ad22 100644
> --- a/arch/s390/kvm/priv.c
> +++ b/arch/s390/kvm/priv.c
> @@ -208,19 +208,23 @@ int kvm_s390_skey_check_enable(struct kvm_vcpu *vcpu)
> struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block;
>
> trace_kvm_s390_skey_related_inst(vcpu);
> - if (!(sie_block->ictl & (ICTL_ISKE | ICTL_SSKE | ICTL_RRBE)) &&
> + /* Already enabled? */
> + if (vcpu->kvm->arch.has_skf &&
> + !(sie_block->ictl & (ICTL_ISKE | ICTL_SSKE | ICTL_RRBE)) &&
> !kvm_s390_test_cpuflags(vcpu, CPUSTAT_KSS))
> return rc;
>
> rc = s390_enable_skey();
> VCPU_EVENT(vcpu, 3, "enabling storage keys for guest: %d", rc);
> - if (!rc) {
> - if (kvm_s390_test_cpuflags(vcpu, CPUSTAT_KSS))
> - kvm_s390_clear_cpuflags(vcpu, CPUSTAT_KSS);
> - else
> - sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE |
> - ICTL_RRBE);
> - }
> + if (rc)
> + return rc;
> +
> + if (kvm_s390_test_cpuflags(vcpu, CPUSTAT_KSS))
> + kvm_s390_clear_cpuflags(vcpu, CPUSTAT_KSS);
> + if (!vcpu->kvm->arch.has_skf)
> + sie_block->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
> + else
> + sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE | ICTL_RRBE);
> return rc;
> }
>
> @@ -231,7 +235,7 @@ static int try_handle_skey(struct kvm_vcpu *vcpu)
> rc = kvm_s390_skey_check_enable(vcpu);
> if (rc)
> return rc;
> - if (sclp.has_skey) {
> + if (vcpu->kvm->arch.has_skf) {
> /* with storage-key facility, SIE interprets it for us */
> kvm_s390_retry_instr(vcpu);
> VCPU_EVENT(vcpu, 4, "%s", "retrying storage key operation");
>
--
Thanks,
David / dhildenb
