Re: [PATCH 2/5] KVM: s390: Add support for machine checks.

[Cornelia Huck <cornelia.huck@de.ibm.com>]

On Mon, 10 Dec 2012 08:51:11 +0100
Alexander Graf <agraf@suse.de> wrote:

> 
> On 07.12.2012, at 13:30, Cornelia Huck wrote:
> 
> > Add support for injecting machine checks (only repressible
> > conditions for now).
> > 
> > This is a bit more involved than I/O interrupts, for these reasons:
> > 
> > - Machine checks come in both floating and cpu varieties.
> > - We don't have a bit for machine checks enabling, but have to use
> >  a roundabout approach with trapping PSW changing instructions and
> >  watching for opened machine checks.
> > 
> > Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
> > Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
> > ---
> > Documentation/virtual/kvm/api.txt |   4 ++
> > arch/s390/include/asm/kvm_host.h  |   8 +++
> > arch/s390/kvm/intercept.c         |   2 +
> > arch/s390/kvm/interrupt.c         | 112 ++++++++++++++++++++++++++++++++
> > arch/s390/kvm/kvm-s390.h          |   3 +
> > arch/s390/kvm/priv.c              | 133 ++++++++++++++++++++++++++++++++++++++
> > arch/s390/kvm/trace-s390.h        |   6 +-
> > include/uapi/linux/kvm.h          |   1 +
> > 8 files changed, 266 insertions(+), 3 deletions(-)
> > 
> > diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
> > index e298a72..8617339 100644
> > --- a/Documentation/virtual/kvm/api.txt
> > +++ b/Documentation/virtual/kvm/api.txt
> > @@ -2072,6 +2072,10 @@ KVM_S390_INT_IO(ai,cssid,ssid,schid) (vm) - compound value to indicate an
> >     I/O interrupt (ai - adapter interrupt; cssid,ssid,schid - subchannel);
> >     I/O interruption parameters in parm (subchannel) and parm64 (intparm,
> >     interruption subclass)
> > +KVM_S390_MCHK (vm, vcpu) - machine check interrupt; cr 14 bits in parm,
> > +                           machine check interrupt code in parm64 (note that
> > +                           machine checks needing further payload are not
> > +                           supported by this ioctl)
> > 
> > Note that the vcpu ioctl is asynchronous to vcpu execution.
> > 
> > diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
> > index e47f697..773859e 100644
> > --- a/arch/s390/include/asm/kvm_host.h
> > +++ b/arch/s390/include/asm/kvm_host.h
> > @@ -77,8 +77,10 @@ struct kvm_s390_sie_block {
> > 	__u8	reserved40[4];		/* 0x0040 */
> > #define LCTL_CR0	0x8000
> > #define LCTL_CR6	0x0200
> > +#define LCTL_CR14	0x0002
> > 	__u16   lctl;			/* 0x0044 */
> > 	__s16	icpua;			/* 0x0046 */
> > +#define ICTL_LPSW 0x00400000
> > 	__u32	ictl;			/* 0x0048 */
> > 	__u32	eca;			/* 0x004c */
> > 	__u8	icptcode;		/* 0x0050 */
> > @@ -189,6 +191,11 @@ struct kvm_s390_emerg_info {
> > 	__u16 code;
> > };
> > 
> > +struct kvm_s390_mchk_info {
> > +	__u64 cr14;
> > +	__u64 mcic;
> > +};
> > +
> > struct kvm_s390_interrupt_info {
> > 	struct list_head list;
> > 	u64	type;
> > @@ -199,6 +206,7 @@ struct kvm_s390_interrupt_info {
> > 		struct kvm_s390_emerg_info emerg;
> > 		struct kvm_s390_extcall_info extcall;
> > 		struct kvm_s390_prefix_info prefix;
> > +		struct kvm_s390_mchk_info mchk;
> > 	};
> > };
> > 
> > diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
> > index 22798ec..ec1177f 100644
> > --- a/arch/s390/kvm/intercept.c
> > +++ b/arch/s390/kvm/intercept.c
> > @@ -106,10 +106,12 @@ static int handle_lctl(struct kvm_vcpu *vcpu)
> > 
> > static intercept_handler_t instruction_handlers[256] = {
> > 	[0x01] = kvm_s390_handle_01,
> > +	[0x82] = kvm_s390_handle_lpsw,
> > 	[0x83] = kvm_s390_handle_diag,
> > 	[0xae] = kvm_s390_handle_sigp,
> > 	[0xb2] = kvm_s390_handle_b2,
> > 	[0xb7] = handle_lctl,
> > +	[0xb9] = kvm_s390_handle_b9,
> > 	[0xe5] = kvm_s390_handle_e5,
> > 	[0xeb] = handle_lctlg,
> > };
> > diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
> > index 070ba22..6b10267 100644
> > --- a/arch/s390/kvm/interrupt.c
> > +++ b/arch/s390/kvm/interrupt.c
> > @@ -41,6 +41,11 @@ static int psw_ioint_disabled(struct kvm_vcpu *vcpu)
> > 	return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO);
> > }
> > 
> > +static int psw_mchk_disabled(struct kvm_vcpu *vcpu)
> > +{
> > +	return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_MCHECK);
> > +}
> > +
> > static int psw_interrupts_disabled(struct kvm_vcpu *vcpu)
> > {
> > 	if ((vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER) ||
> > @@ -82,6 +87,12 @@ static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
> > 	case KVM_S390_SIGP_SET_PREFIX:
> > 	case KVM_S390_RESTART:
> > 		return 1;
> > +	case KVM_S390_MCHK:
> > +		if (psw_mchk_disabled(vcpu))
> > +			return 0;
> > +		if (vcpu->arch.sie_block->gcr[14] & inti->mchk.cr14)
> > +			return 1;
> > +		return 0;
> > 	default:
> > 		if (is_ioint(inti->type)) {
> > 			if (psw_ioint_disabled(vcpu))
> > @@ -119,6 +130,7 @@ static void __reset_intercept_indicators(struct kvm_vcpu *vcpu)
> > 		CPUSTAT_IO_INT | CPUSTAT_EXT_INT | CPUSTAT_STOP_INT,
> > 		&vcpu->arch.sie_block->cpuflags);
> > 	vcpu->arch.sie_block->lctl = 0x0000;
> > +	vcpu->arch.sie_block->ictl &= ~ICTL_LPSW;
> > }
> > 
> > static void __set_cpuflag(struct kvm_vcpu *vcpu, u32 flag)
> > @@ -142,6 +154,12 @@ static void __set_intercept_indicator(struct kvm_vcpu *vcpu,
> > 	case KVM_S390_SIGP_STOP:
> > 		__set_cpuflag(vcpu, CPUSTAT_STOP_INT);
> > 		break;
> > +	case KVM_S390_MCHK:
> > +		if (psw_mchk_disabled(vcpu))
> > +			vcpu->arch.sie_block->ictl |= ICTL_LPSW;
> > +		else
> > +			vcpu->arch.sie_block->lctl |= LCTL_CR14;
> > +		break;
> > 	default:
> > 		if (is_ioint(inti->type)) {
> > 			if (psw_ioint_disabled(vcpu))
> > @@ -330,6 +348,32 @@ static void __do_deliver_interrupt(struct kvm_vcpu *vcpu,
> > 			exception = 1;
> > 		break;
> > 
> > +	case KVM_S390_MCHK:
> > +		VCPU_EVENT(vcpu, 4, "interrupt: machine check mcic=%llx",
> > +			   inti->mchk.mcic);
> > +		trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type,
> > +						 inti->mchk.cr14,
> > +						 inti->mchk.mcic);
> > +		rc = kvm_s390_vcpu_store_status(vcpu,
> > +						KVM_S390_STORE_STATUS_PREFIXED);
> > +		if (rc == -EFAULT)
> > +			exception = 1;
> > +
> > +		rc = put_guest_u64(vcpu, __LC_MCCK_CODE, inti->mchk.mcic);
> > +		if (rc == -EFAULT)
> > +			exception = 1;
> > +
> > +		rc = copy_to_guest(vcpu, __LC_MCK_OLD_PSW,
> > +				   &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
> > +		if (rc == -EFAULT)
> > +			exception = 1;
> > +
> > +		rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
> > +				     __LC_MCK_NEW_PSW, sizeof(psw_t));
> > +		if (rc == -EFAULT)
> > +			exception = 1;
> > +		break;
> > +
> > 	default:
> > 		if (is_ioint(inti->type)) {
> > 			__u32 param0 = ((__u32)inti->io.subchannel_id << 16) |
> > @@ -593,6 +637,61 @@ void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
> > 	}
> > }
> > 
> > +void kvm_s390_deliver_pending_machine_checks(struct kvm_vcpu *vcpu)
> > +{
> > +	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
> > +	struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
> > +	struct kvm_s390_interrupt_info  *n, *inti = NULL;
> > +	int deliver;
> > +
> > +	__reset_intercept_indicators(vcpu);
> > +	if (atomic_read(&li->active)) {
> > +		do {
> > +			deliver = 0;
> > +			spin_lock_bh(&li->lock);
> > +			list_for_each_entry_safe(inti, n, &li->list, list) {
> > +				if ((inti->type == KVM_S390_MCHK) &&
> > +				    __interrupt_is_deliverable(vcpu, inti)) {
> > +					list_del(&inti->list);
> > +					deliver = 1;
> > +					break;
> > +				}
> > +				__set_intercept_indicator(vcpu, inti);
> > +			}
> > +			if (list_empty(&li->list))
> > +				atomic_set(&li->active, 0);
> > +			spin_unlock_bh(&li->lock);
> > +			if (deliver) {
> > +				__do_deliver_interrupt(vcpu, inti);
> > +				kfree(inti);
> > +			}
> > +		} while (deliver);
> > +	}
> > +
> > +	if (atomic_read(&fi->active)) {
> > +		do {
> > +			deliver = 0;
> > +			spin_lock(&fi->lock);
> > +			list_for_each_entry_safe(inti, n, &fi->list, list) {
> > +				if ((inti->type == KVM_S390_MCHK) &&
> > +				    __interrupt_is_deliverable(vcpu, inti)) {
> > +					list_del(&inti->list);
> > +					deliver = 1;
> > +					break;
> > +				}
> > +				__set_intercept_indicator(vcpu, inti);
> > +			}
> > +			if (list_empty(&fi->list))
> > +				atomic_set(&fi->active, 0);
> > +			spin_unlock(&fi->lock);
> > +			if (deliver) {
> > +				__do_deliver_interrupt(vcpu, inti);
> > +				kfree(inti);
> > +			}
> > +		} while (deliver);
> > +	}
> > +}
> > +
> > int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code)
> > {
> > 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
> > @@ -646,6 +745,13 @@ int kvm_s390_inject_vm(struct kvm *kvm,
> > 	case KVM_S390_INT_EMERGENCY:
> > 		kfree(inti);
> > 		return -EINVAL;
> > +	case KVM_S390_MCHK:
> > +		VM_EVENT(kvm, 5, "inject: machine check parm64:%llx",
> > +			 s390int->parm64);
> > +		inti->type = s390int->type;
> > +		inti->mchk.cr14 = s390int->parm; /* upper bits are not used */
> > +		inti->mchk.mcic = s390int->parm64;
> > +		break;
> > 	default:
> > 		if (!is_ioint(s390int->type)) {
> > 			kfree(inti);
> > @@ -755,6 +861,12 @@ int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
> > 		inti->type = s390int->type;
> > 		inti->emerg.code = s390int->parm;
> > 		break;
> > +	case KVM_S390_MCHK:
> > +		VCPU_EVENT(vcpu, 5, "inject: machine check parm64:%llx",
> > +			   s390int->parm64);
> > +		inti->type = s390int->type;
> > +		inti->mchk.mcic = s390int->parm64;
> > +		break;
> > 	case KVM_S390_INT_VIRTIO:
> > 	case KVM_S390_INT_SERVICE:
> > 	default:
> > diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
> > index d75bc5e..b1e1cb6 100644
> > --- a/arch/s390/kvm/kvm-s390.h
> > +++ b/arch/s390/kvm/kvm-s390.h
> > @@ -69,6 +69,7 @@ int kvm_s390_handle_wait(struct kvm_vcpu *vcpu);
> > enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer);
> > void kvm_s390_tasklet(unsigned long parm);
> > void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu);
> > +void kvm_s390_deliver_pending_machine_checks(struct kvm_vcpu *vcpu);
> > int kvm_s390_inject_vm(struct kvm *kvm,
> > 		struct kvm_s390_interrupt *s390int);
> > int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
> > @@ -80,6 +81,8 @@ int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action);
> > int kvm_s390_handle_b2(struct kvm_vcpu *vcpu);
> > int kvm_s390_handle_e5(struct kvm_vcpu *vcpu);
> > int kvm_s390_handle_01(struct kvm_vcpu *vcpu);
> > +int kvm_s390_handle_b9(struct kvm_vcpu *vcpu);
> > +int kvm_s390_handle_lpsw(struct kvm_vcpu *vcpu);
> > 
> > /* implemented in sigp.c */
> > int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu);
> > diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
> > index d768906..66258b9 100644
> > --- a/arch/s390/kvm/priv.c
> > +++ b/arch/s390/kvm/priv.c
> > @@ -176,6 +176,101 @@ static int handle_stfl(struct kvm_vcpu *vcpu)
> > 	return 0;
> > }
> > 
> > +static void handle_new_psw(struct kvm_vcpu *vcpu)
> > +{
> > +	/* Check whether the new psw is enabled for machine checks. */
> > +	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_MCHECK)
> > +		kvm_s390_deliver_pending_machine_checks(vcpu);
> > +}
> > +
> > +int kvm_s390_handle_lpsw(struct kvm_vcpu *vcpu)
> > +{
> > +	int base2 = vcpu->arch.sie_block->ipb >> 28;
> > +	int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
> > +	u64 addr;
> > +	u64 uninitialized_var(new_psw);
> > +
> > +	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
> > +		return kvm_s390_inject_program_int(vcpu,
> > +						   PGM_PRIVILEGED_OPERATION);
> > +
> > +	addr = disp2;
> > +	if (base2)
> > +		addr += vcpu->run->s.regs.gprs[base2];
> 
> This is a pretty common address offset scheme. Please extract it into a separate function (which the compiler will inline again).
> 
> > +
> > +	if (addr & 7) {
> > +		kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
> > +		goto out;
> > +	}
> > +
> > +	if (get_guest_u64(vcpu, addr, &new_psw)) {
> > +		kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
> > +		goto out;
> > +	}
> > +
> > +	if (!(new_psw & 0x0008000000000000)) {
> 
> Magic number? Doesn't this bit have a name?
> 
> > +		kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
> > +		goto out;
> > +	}
> > +
> > +	vcpu->arch.sie_block->gpsw.mask = new_psw & 0xfff7ffff80000000;
> > +	vcpu->arch.sie_block->gpsw.addr = new_psw & 0x000000007fffffff;
> > +
> > +	if ((vcpu->arch.sie_block->gpsw.mask & 0xb80800fe00000000) ||
> > +	    (!(vcpu->arch.sie_block->gpsw.mask & 0x0000000180000000) &&
> > +	     (vcpu->arch.sie_block->gpsw.addr & 0x000000007ff00000)) ||
> > +	    ((vcpu->arch.sie_block->gpsw.mask & 0x0000000180000000) ==
> > +	     0x0000000100000000)) {
> > +		kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
> 
> Lots of magic numbers :). I'm sure these have names too ;). I really like to be able to read this cod without looking at the POP all the time.

I'll see what I can come up with.

> 
> > +		goto out;
> > +	}
> > +
> > +	handle_new_psw(vcpu);
> > +out:
> > +	return 0;
> > +}
> > +
> > +static int handle_lpswe(struct kvm_vcpu *vcpu)
> > +{
> > +	int base2 = vcpu->arch.sie_block->ipb >> 28;
> > +	int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
> > +	u64 addr;
> > +	psw_t new_psw;
> > +
> > +	addr = disp2;
> > +	if (base2)
> > +		addr += vcpu->run->s.regs.gprs[base2];
> > +
> > +	if (addr & 7) {
> > +		kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
> > +		goto out;
> > +	}
> > +
> > +	if (copy_from_guest(vcpu, &new_psw, addr, sizeof(new_psw))) {
> > +		kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
> > +		goto out;
> > +	}
> > +
> > +	vcpu->arch.sie_block->gpsw.mask = new_psw.mask;
> > +	vcpu->arch.sie_block->gpsw.addr = new_psw.addr;
> > +
> > +	if ((vcpu->arch.sie_block->gpsw.mask & 0xb80800fe7fffffff) ||
> > +	    (((vcpu->arch.sie_block->gpsw.mask & 0x0000000180000000) ==
> > +	      0x0000000080000000) &&
> > +	     (vcpu->arch.sie_block->gpsw.addr & 0xffffffff80000000)) ||
> > +	    (!(vcpu->arch.sie_block->gpsw.mask & 0x0000000180000000) &&
> > +	     (vcpu->arch.sie_block->gpsw.addr & 0xfffffffffff00000)) ||
> > +	    ((vcpu->arch.sie_block->gpsw.mask & 0x0000000180000000) ==
> > +	     0x0000000100000000)) {
> > +		kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
> > +		goto out;
> > +	}
> 
> That function looks quite similar to the one above. Any chance to move them together?

The checks are not quite the same.

> 
> Alex
> 
> > +
> > +	handle_new_psw(vcpu);
> > +out:
> > +	return 0;
> > +}
> > +
> > static int handle_stidp(struct kvm_vcpu *vcpu)
> > {
> > 	int base2 = vcpu->arch.sie_block->ipb >> 28;
> > @@ -309,6 +404,7 @@ static intercept_handler_t priv_handlers[256] = {
> > 	[0x5f] = handle_chsc,
> > 	[0x7d] = handle_stsi,
> > 	[0xb1] = handle_stfl,
> > +	[0xb2] = handle_lpswe,
> > };
> > 
> > int kvm_s390_handle_b2(struct kvm_vcpu *vcpu)
> > @@ -333,6 +429,43 @@ int kvm_s390_handle_b2(struct kvm_vcpu *vcpu)
> > 	return -EOPNOTSUPP;
> > }
> > 
> > +static int handle_epsw(struct kvm_vcpu *vcpu)
> > +{
> > +	int reg1, reg2;
> > +
> > +	reg1 = (vcpu->arch.sie_block->ipb & 0x00f00000) >> 24;
> > +	reg2 = (vcpu->arch.sie_block->ipb & 0x000f0000) >> 16;
> > +	vcpu->run->s.regs.gprs[reg1] &= 0xffffffff00000000;
> > +	vcpu->run->s.regs.gprs[reg1] |= vcpu->arch.sie_block->gpsw.mask >> 32;
> > +	if (reg2) {
> > +		vcpu->run->s.regs.gprs[reg2] &= 0xffffffff00000000;
> > +		vcpu->run->s.regs.gprs[reg2] |=
> > +			vcpu->arch.sie_block->gpsw.mask & 0x00000000ffffffff;
> > +	}
> > +	return 0;
> > +}
> > +
> > +static intercept_handler_t b9_handlers[256] = {
> > +	[0x8d] = handle_epsw,
> > +};
> > +
> > +int kvm_s390_handle_b9(struct kvm_vcpu *vcpu)
> > +{
> > +	intercept_handler_t handler;
> > +
> > +	/* This is handled just as for the B2 instructions. */
> > +	handler = b9_handlers[vcpu->arch.sie_block->ipa & 0x00ff];
> > +	if (handler) {
> > +		if ((handler != handle_epsw) &&
> > +		    (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE))
> > +			return kvm_s390_inject_program_int(vcpu,
> > +						   PGM_PRIVILEGED_OPERATION);
> > +		else
> > +			return handler(vcpu);
> > +	}
> > +	return -EOPNOTSUPP;
> > +}
> > +
> > static int handle_tprot(struct kvm_vcpu *vcpu)
> > {
> > 	int base1 = (vcpu->arch.sie_block->ipb & 0xf0000000) >> 28;
> > diff --git a/arch/s390/kvm/trace-s390.h b/arch/s390/kvm/trace-s390.h
> > index 90fdf85..95fbc1a 100644
> > --- a/arch/s390/kvm/trace-s390.h
> > +++ b/arch/s390/kvm/trace-s390.h
> > @@ -141,13 +141,13 @@ TRACE_EVENT(kvm_s390_inject_vcpu,
> >  * Trace point for the actual delivery of interrupts.
> >  */
> > TRACE_EVENT(kvm_s390_deliver_interrupt,
> > -	    TP_PROTO(unsigned int id, __u64 type, __u32 data0, __u64 data1),
> > +	    TP_PROTO(unsigned int id, __u64 type, __u64 data0, __u64 data1),
> > 	    TP_ARGS(id, type, data0, data1),
> > 
> > 	    TP_STRUCT__entry(
> > 		    __field(int, id)
> > 		    __field(__u32, inttype)
> > -		    __field(__u32, data0)
> > +		    __field(__u64, data0)
> > 		    __field(__u64, data1)
> > 		    ),
> > 
> > @@ -159,7 +159,7 @@ TRACE_EVENT(kvm_s390_deliver_interrupt,
> > 		    ),
> > 
> > 	    TP_printk("deliver interrupt (vcpu %d): type:%x (%s) "	\
> > -		      "data:%08x %016llx",
> > +		      "data:%08llx %016llx",
> > 		      __entry->id, __entry->inttype,
> > 		      __print_symbolic(__entry->inttype, kvm_s390_int_type),
> > 		      __entry->data0, __entry->data1)
> > diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> > index e676940..22859dc 100644
> > --- a/include/uapi/linux/kvm.h
> > +++ b/include/uapi/linux/kvm.h
> > @@ -397,6 +397,7 @@ struct kvm_s390_psw {
> > #define KVM_S390_PROGRAM_INT		0xfffe0001u
> > #define KVM_S390_SIGP_SET_PREFIX	0xfffe0002u
> > #define KVM_S390_RESTART		0xfffe0003u
> > +#define KVM_S390_MCHK			0xfffe1000u
> > #define KVM_S390_INT_VIRTIO		0xffff2603u
> > #define KVM_S390_INT_SERVICE		0xffff2401u
> > #define KVM_S390_INT_EMERGENCY		0xffff1201u
> > -- 
> > 1.7.12.4
> > 
>