On 16.10.20 09:34, Janosch Frank wrote: > On 10/15/20 9:59 PM, Collin Walling wrote: >> The DIAGNOSE 0x0318 instruction must be reset on a normal and clear >> reset. However, this was missed for the clear reset case. >> >> Let's fix this by resetting the information during a normal reset. >> Since clear reset is a superset of normal reset, the info will >> still reset on a clear reset. > > The architecture really confuses me here but I think we don't want this > in the kernel VCPU reset handlers at all. > > This needs to be reset per VM *NOT* per VCPU. > Hence the resets are bound to diag308 and not SIGP. > > I.e. we need to clear it in QEMU's VM reset handler. > It's still early and I have yet to consume my first coffee, am I missing > something? I agree with Janosch. architecture indicates that this should only be reset for VM-wide resets, e.g. sigp orders 11 and 12 are explicitly mentioned to NOT reset the value. > >> >> Signed-off-by: Collin Walling <walling@xxxxxxxxxxxxx> >> --- >> arch/s390/kvm/kvm-s390.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c >> index 6b74b92c1a58..b0cf8367e261 100644 >> --- a/arch/s390/kvm/kvm-s390.c >> +++ b/arch/s390/kvm/kvm-s390.c >> @@ -3516,6 +3516,7 @@ static void kvm_arch_vcpu_ioctl_normal_reset(struct kvm_vcpu *vcpu) >> vcpu->arch.sie_block->gpsw.mask &= ~PSW_MASK_RI; >> vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID; >> memset(vcpu->run->s.regs.riccb, 0, sizeof(vcpu->run->s.regs.riccb)); >> + vcpu->run->s.regs.diag318 = 0; >> >> kvm_clear_async_pf_completion_queue(vcpu); >> if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) >> @@ -3582,7 +3583,6 @@ static void kvm_arch_vcpu_ioctl_clear_reset(struct kvm_vcpu *vcpu) >> >> regs->etoken = 0; >> regs->etoken_extension = 0; >> - regs->diag318 = 0; >> } >> >> int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) >> > >
