diff --git a/arch/s390/kvm/guestdbg.c b/arch/s390/kvm/guestdbg.c index e97b3455d7e6..47518a324d75 100644 --- a/arch/s390/kvm/guestdbg.c +++ b/arch/s390/kvm/guestdbg.c @@ -473,10 +473,45 @@ static void filter_guest_per_event(struct kvm_vcpu *vcpu) vcpu->arch.sie_block->iprcc &= ~PGM_PER; } +#define pssec(vcpu) (vcpu->arch.sie_block->gcr[1] & _ASCE_SPACE_SWITCH) +#define hssec(vcpu) (vcpu->arch.sie_block->gcr[13] & _ASCE_SPACE_SWITCH) +#define old_ssec(vcpu) ((vcpu->arch.sie_block->tecmc >> 31) & 0x1) +#define old_as_is_home(vcpu) !(vcpu->arch.sie_block->tecmc & 0xffff) + void kvm_s390_handle_per_event(struct kvm_vcpu *vcpu) { + int new_as; + if (debug_exit_required(vcpu)) vcpu->guest_debug |= KVM_GUESTDBG_EXIT_PENDING; filter_guest_per_event(vcpu); + + /* + * Only RP, SAC, SACF, PT, PTI, PR, PC instructions can trigger + * a space-switch event. PER events enforce space-switch events + * for these instructions. So if no PER event for the guest is left, + * we might have to filter the space-switch element out, too. + */ + if (vcpu->arch.sie_block->iprcc == PGM_SPACE_SWITCH) { + vcpu->arch.sie_block->iprcc = 0; + new_as = psw_bits(vcpu->arch.sie_block->gpsw).as; + + /* + * If the AS changed from / to home, we had RP, SAC or SACF + * instruction. Check primary and home space-switch-event + * controls. (theoretically home -> home produced no event) + */ + if (((new_as == PSW_AS_HOME) ^ old_as_is_home(vcpu)) && + (pssec(vcpu) || hssec(vcpu))) + vcpu->arch.sie_block->iprcc = PGM_SPACE_SWITCH; + + /* + * PT, PTI, PR, PC instruction operate on primary AS only. Check + * if the primary-space-switch-event control was or got set. + */ + if (new_as == PSW_AS_PRIMARY && !old_as_is_home(vcpu) && + (pssec(vcpu) || old_ssec(vcpu))) + vcpu->arch.sie_block->iprcc = PGM_SPACE_SWITCH; + } }