linux/arch/s390/kvm/interrupt.c
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   1/*
   2 * interrupt.c - handling kvm guest interrupts
   3 *
   4 * Copyright IBM Corp. 2008
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License (version 2 only)
   8 * as published by the Free Software Foundation.
   9 *
  10 *    Author(s): Carsten Otte <cotte@de.ibm.com>
  11 */
  12
  13#include <asm/lowcore.h>
  14#include <asm/uaccess.h>
  15#include <linux/kvm_host.h>
  16#include <linux/signal.h>
  17#include "kvm-s390.h"
  18#include "gaccess.h"
  19
  20static int psw_extint_disabled(struct kvm_vcpu *vcpu)
  21{
  22        return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT);
  23}
  24
  25static int psw_interrupts_disabled(struct kvm_vcpu *vcpu)
  26{
  27        if ((vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER) ||
  28            (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO) ||
  29            (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT))
  30                return 0;
  31        return 1;
  32}
  33
  34static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
  35                                      struct kvm_s390_interrupt_info *inti)
  36{
  37        switch (inti->type) {
  38        case KVM_S390_INT_EMERGENCY:
  39                if (psw_extint_disabled(vcpu))
  40                        return 0;
  41                if (vcpu->arch.sie_block->gcr[0] & 0x4000ul)
  42                        return 1;
  43                return 0;
  44        case KVM_S390_INT_SERVICE:
  45                if (psw_extint_disabled(vcpu))
  46                        return 0;
  47                if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
  48                        return 1;
  49                return 0;
  50        case KVM_S390_INT_VIRTIO:
  51                if (psw_extint_disabled(vcpu))
  52                        return 0;
  53                if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
  54                        return 1;
  55                return 0;
  56        case KVM_S390_PROGRAM_INT:
  57        case KVM_S390_SIGP_STOP:
  58        case KVM_S390_SIGP_SET_PREFIX:
  59        case KVM_S390_RESTART:
  60                return 1;
  61        default:
  62                BUG();
  63        }
  64        return 0;
  65}
  66
  67static void __set_cpu_idle(struct kvm_vcpu *vcpu)
  68{
  69        BUG_ON(vcpu->vcpu_id > KVM_MAX_VCPUS - 1);
  70        atomic_set_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
  71        set_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
  72}
  73
  74static void __unset_cpu_idle(struct kvm_vcpu *vcpu)
  75{
  76        BUG_ON(vcpu->vcpu_id > KVM_MAX_VCPUS - 1);
  77        atomic_clear_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
  78        clear_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
  79}
  80
  81static void __reset_intercept_indicators(struct kvm_vcpu *vcpu)
  82{
  83        atomic_clear_mask(CPUSTAT_ECALL_PEND |
  84                CPUSTAT_IO_INT | CPUSTAT_EXT_INT | CPUSTAT_STOP_INT,
  85                &vcpu->arch.sie_block->cpuflags);
  86        vcpu->arch.sie_block->lctl = 0x0000;
  87}
  88
  89static void __set_cpuflag(struct kvm_vcpu *vcpu, u32 flag)
  90{
  91        atomic_set_mask(flag, &vcpu->arch.sie_block->cpuflags);
  92}
  93
  94static void __set_intercept_indicator(struct kvm_vcpu *vcpu,
  95                                      struct kvm_s390_interrupt_info *inti)
  96{
  97        switch (inti->type) {
  98        case KVM_S390_INT_EMERGENCY:
  99        case KVM_S390_INT_SERVICE:
 100        case KVM_S390_INT_VIRTIO:
 101                if (psw_extint_disabled(vcpu))
 102                        __set_cpuflag(vcpu, CPUSTAT_EXT_INT);
 103                else
 104                        vcpu->arch.sie_block->lctl |= LCTL_CR0;
 105                break;
 106        case KVM_S390_SIGP_STOP:
 107                __set_cpuflag(vcpu, CPUSTAT_STOP_INT);
 108                break;
 109        default:
 110                BUG();
 111        }
 112}
 113
 114static void __do_deliver_interrupt(struct kvm_vcpu *vcpu,
 115                                   struct kvm_s390_interrupt_info *inti)
 116{
 117        const unsigned short table[] = { 2, 4, 4, 6 };
 118        int rc, exception = 0;
 119
 120        switch (inti->type) {
 121        case KVM_S390_INT_EMERGENCY:
 122                VCPU_EVENT(vcpu, 4, "%s", "interrupt: sigp emerg");
 123                vcpu->stat.deliver_emergency_signal++;
 124                rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1201);
 125                if (rc == -EFAULT)
 126                        exception = 1;
 127
 128                rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
 129                         &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 130                if (rc == -EFAULT)
 131                        exception = 1;
 132
 133                rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 134                        __LC_EXT_NEW_PSW, sizeof(psw_t));
 135                if (rc == -EFAULT)
 136                        exception = 1;
 137                break;
 138
 139        case KVM_S390_INT_SERVICE:
 140                VCPU_EVENT(vcpu, 4, "interrupt: sclp parm:%x",
 141                           inti->ext.ext_params);
 142                vcpu->stat.deliver_service_signal++;
 143                rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x2401);
 144                if (rc == -EFAULT)
 145                        exception = 1;
 146
 147                rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
 148                         &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 149                if (rc == -EFAULT)
 150                        exception = 1;
 151
 152                rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 153                        __LC_EXT_NEW_PSW, sizeof(psw_t));
 154                if (rc == -EFAULT)
 155                        exception = 1;
 156
 157                rc = put_guest_u32(vcpu, __LC_EXT_PARAMS, inti->ext.ext_params);
 158                if (rc == -EFAULT)
 159                        exception = 1;
 160                break;
 161
 162        case KVM_S390_INT_VIRTIO:
 163                VCPU_EVENT(vcpu, 4, "interrupt: virtio parm:%x,parm64:%lx",
 164                           inti->ext.ext_params, inti->ext.ext_params2);
 165                vcpu->stat.deliver_virtio_interrupt++;
 166                rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x2603);
 167                if (rc == -EFAULT)
 168                        exception = 1;
 169
 170                rc = put_guest_u16(vcpu, __LC_CPU_ADDRESS, 0x0d00);
 171                if (rc == -EFAULT)
 172                        exception = 1;
 173
 174                rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
 175                         &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 176                if (rc == -EFAULT)
 177                        exception = 1;
 178
 179                rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 180                        __LC_EXT_NEW_PSW, sizeof(psw_t));
 181                if (rc == -EFAULT)
 182                        exception = 1;
 183
 184                rc = put_guest_u32(vcpu, __LC_EXT_PARAMS, inti->ext.ext_params);
 185                if (rc == -EFAULT)
 186                        exception = 1;
 187
 188                rc = put_guest_u64(vcpu, __LC_PFAULT_INTPARM,
 189                        inti->ext.ext_params2);
 190                if (rc == -EFAULT)
 191                        exception = 1;
 192                break;
 193
 194        case KVM_S390_SIGP_STOP:
 195                VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu stop");
 196                vcpu->stat.deliver_stop_signal++;
 197                __set_intercept_indicator(vcpu, inti);
 198                break;
 199
 200        case KVM_S390_SIGP_SET_PREFIX:
 201                VCPU_EVENT(vcpu, 4, "interrupt: set prefix to %x",
 202                           inti->prefix.address);
 203                vcpu->stat.deliver_prefix_signal++;
 204                vcpu->arch.sie_block->prefix = inti->prefix.address;
 205                vcpu->arch.sie_block->ihcpu = 0xffff;
 206                break;
 207
 208        case KVM_S390_RESTART:
 209                VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu restart");
 210                vcpu->stat.deliver_restart_signal++;
 211                rc = copy_to_guest(vcpu, offsetof(struct _lowcore,
 212                  restart_old_psw), &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 213                if (rc == -EFAULT)
 214                        exception = 1;
 215
 216                rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 217                        offsetof(struct _lowcore, restart_psw), sizeof(psw_t));
 218                if (rc == -EFAULT)
 219                        exception = 1;
 220                break;
 221
 222        case KVM_S390_PROGRAM_INT:
 223                VCPU_EVENT(vcpu, 4, "interrupt: pgm check code:%x, ilc:%x",
 224                           inti->pgm.code,
 225                           table[vcpu->arch.sie_block->ipa >> 14]);
 226                vcpu->stat.deliver_program_int++;
 227                rc = put_guest_u16(vcpu, __LC_PGM_INT_CODE, inti->pgm.code);
 228                if (rc == -EFAULT)
 229                        exception = 1;
 230
 231                rc = put_guest_u16(vcpu, __LC_PGM_ILC,
 232                        table[vcpu->arch.sie_block->ipa >> 14]);
 233                if (rc == -EFAULT)
 234                        exception = 1;
 235
 236                rc = copy_to_guest(vcpu, __LC_PGM_OLD_PSW,
 237                         &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 238                if (rc == -EFAULT)
 239                        exception = 1;
 240
 241                rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 242                        __LC_PGM_NEW_PSW, sizeof(psw_t));
 243                if (rc == -EFAULT)
 244                        exception = 1;
 245                break;
 246
 247        default:
 248                BUG();
 249        }
 250        if (exception) {
 251                printk("kvm: The guest lowcore is not mapped during interrupt "
 252                        "delivery, killing userspace\n");
 253                do_exit(SIGKILL);
 254        }
 255}
 256
 257static int __try_deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
 258{
 259        int rc, exception = 0;
 260
 261        if (psw_extint_disabled(vcpu))
 262                return 0;
 263        if (!(vcpu->arch.sie_block->gcr[0] & 0x800ul))
 264                return 0;
 265        rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1004);
 266        if (rc == -EFAULT)
 267                exception = 1;
 268        rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
 269                 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 270        if (rc == -EFAULT)
 271                exception = 1;
 272        rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 273                __LC_EXT_NEW_PSW, sizeof(psw_t));
 274        if (rc == -EFAULT)
 275                exception = 1;
 276        if (exception) {
 277                printk("kvm: The guest lowcore is not mapped during interrupt "
 278                        "delivery, killing userspace\n");
 279                do_exit(SIGKILL);
 280        }
 281        return 1;
 282}
 283
 284int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
 285{
 286        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 287        struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
 288        struct kvm_s390_interrupt_info  *inti;
 289        int rc = 0;
 290
 291        if (atomic_read(&li->active)) {
 292                spin_lock_bh(&li->lock);
 293                list_for_each_entry(inti, &li->list, list)
 294                        if (__interrupt_is_deliverable(vcpu, inti)) {
 295                                rc = 1;
 296                                break;
 297                        }
 298                spin_unlock_bh(&li->lock);
 299        }
 300
 301        if ((!rc) && atomic_read(&fi->active)) {
 302                spin_lock_bh(&fi->lock);
 303                list_for_each_entry(inti, &fi->list, list)
 304                        if (__interrupt_is_deliverable(vcpu, inti)) {
 305                                rc = 1;
 306                                break;
 307                        }
 308                spin_unlock_bh(&fi->lock);
 309        }
 310
 311        if ((!rc) && (vcpu->arch.sie_block->ckc <
 312                get_clock() + vcpu->arch.sie_block->epoch)) {
 313                if ((!psw_extint_disabled(vcpu)) &&
 314                        (vcpu->arch.sie_block->gcr[0] & 0x800ul))
 315                        rc = 1;
 316        }
 317
 318        return rc;
 319}
 320
 321int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 322{
 323        return 0;
 324}
 325
 326int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
 327{
 328        u64 now, sltime;
 329        DECLARE_WAITQUEUE(wait, current);
 330
 331        vcpu->stat.exit_wait_state++;
 332        if (kvm_cpu_has_interrupt(vcpu))
 333                return 0;
 334
 335        __set_cpu_idle(vcpu);
 336        spin_lock_bh(&vcpu->arch.local_int.lock);
 337        vcpu->arch.local_int.timer_due = 0;
 338        spin_unlock_bh(&vcpu->arch.local_int.lock);
 339
 340        if (psw_interrupts_disabled(vcpu)) {
 341                VCPU_EVENT(vcpu, 3, "%s", "disabled wait");
 342                __unset_cpu_idle(vcpu);
 343                return -ENOTSUPP; /* disabled wait */
 344        }
 345
 346        if (psw_extint_disabled(vcpu) ||
 347            (!(vcpu->arch.sie_block->gcr[0] & 0x800ul))) {
 348                VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer");
 349                goto no_timer;
 350        }
 351
 352        now = get_clock() + vcpu->arch.sie_block->epoch;
 353        if (vcpu->arch.sie_block->ckc < now) {
 354                __unset_cpu_idle(vcpu);
 355                return 0;
 356        }
 357
 358        sltime = (vcpu->arch.sie_block->ckc - now) / (0xf4240000ul / HZ) + 1;
 359
 360        vcpu->arch.ckc_timer.expires = jiffies + sltime;
 361
 362        add_timer(&vcpu->arch.ckc_timer);
 363        VCPU_EVENT(vcpu, 5, "enabled wait timer:%lx jiffies", sltime);
 364no_timer:
 365        spin_lock_bh(&vcpu->arch.local_int.float_int->lock);
 366        spin_lock_bh(&vcpu->arch.local_int.lock);
 367        add_wait_queue(&vcpu->arch.local_int.wq, &wait);
 368        while (list_empty(&vcpu->arch.local_int.list) &&
 369                list_empty(&vcpu->arch.local_int.float_int->list) &&
 370                (!vcpu->arch.local_int.timer_due) &&
 371                !signal_pending(current)) {
 372                set_current_state(TASK_INTERRUPTIBLE);
 373                spin_unlock_bh(&vcpu->arch.local_int.lock);
 374                spin_unlock_bh(&vcpu->arch.local_int.float_int->lock);
 375                vcpu_put(vcpu);
 376                schedule();
 377                vcpu_load(vcpu);
 378                spin_lock_bh(&vcpu->arch.local_int.float_int->lock);
 379                spin_lock_bh(&vcpu->arch.local_int.lock);
 380        }
 381        __unset_cpu_idle(vcpu);
 382        __set_current_state(TASK_RUNNING);
 383        remove_wait_queue(&vcpu->wq, &wait);
 384        spin_unlock_bh(&vcpu->arch.local_int.lock);
 385        spin_unlock_bh(&vcpu->arch.local_int.float_int->lock);
 386        del_timer(&vcpu->arch.ckc_timer);
 387        return 0;
 388}
 389
 390void kvm_s390_idle_wakeup(unsigned long data)
 391{
 392        struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
 393
 394        spin_lock_bh(&vcpu->arch.local_int.lock);
 395        vcpu->arch.local_int.timer_due = 1;
 396        if (waitqueue_active(&vcpu->arch.local_int.wq))
 397                wake_up_interruptible(&vcpu->arch.local_int.wq);
 398        spin_unlock_bh(&vcpu->arch.local_int.lock);
 399}
 400
 401
 402void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
 403{
 404        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 405        struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
 406        struct kvm_s390_interrupt_info  *n, *inti = NULL;
 407        int deliver;
 408
 409        __reset_intercept_indicators(vcpu);
 410        if (atomic_read(&li->active)) {
 411                do {
 412                        deliver = 0;
 413                        spin_lock_bh(&li->lock);
 414                        list_for_each_entry_safe(inti, n, &li->list, list) {
 415                                if (__interrupt_is_deliverable(vcpu, inti)) {
 416                                        list_del(&inti->list);
 417                                        deliver = 1;
 418                                        break;
 419                                }
 420                                __set_intercept_indicator(vcpu, inti);
 421                        }
 422                        if (list_empty(&li->list))
 423                                atomic_set(&li->active, 0);
 424                        spin_unlock_bh(&li->lock);
 425                        if (deliver) {
 426                                __do_deliver_interrupt(vcpu, inti);
 427                                kfree(inti);
 428                        }
 429                } while (deliver);
 430        }
 431
 432        if ((vcpu->arch.sie_block->ckc <
 433                get_clock() + vcpu->arch.sie_block->epoch))
 434                __try_deliver_ckc_interrupt(vcpu);
 435
 436        if (atomic_read(&fi->active)) {
 437                do {
 438                        deliver = 0;
 439                        spin_lock_bh(&fi->lock);
 440                        list_for_each_entry_safe(inti, n, &fi->list, list) {
 441                                if (__interrupt_is_deliverable(vcpu, inti)) {
 442                                        list_del(&inti->list);
 443                                        deliver = 1;
 444                                        break;
 445                                }
 446                                __set_intercept_indicator(vcpu, inti);
 447                        }
 448                        if (list_empty(&fi->list))
 449                                atomic_set(&fi->active, 0);
 450                        spin_unlock_bh(&fi->lock);
 451                        if (deliver) {
 452                                __do_deliver_interrupt(vcpu, inti);
 453                                kfree(inti);
 454                        }
 455                } while (deliver);
 456        }
 457}
 458
 459int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code)
 460{
 461        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 462        struct kvm_s390_interrupt_info *inti;
 463
 464        inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 465        if (!inti)
 466                return -ENOMEM;
 467
 468        inti->type = KVM_S390_PROGRAM_INT;;
 469        inti->pgm.code = code;
 470
 471        VCPU_EVENT(vcpu, 3, "inject: program check %d (from kernel)", code);
 472        spin_lock_bh(&li->lock);
 473        list_add(&inti->list, &li->list);
 474        atomic_set(&li->active, 1);
 475        BUG_ON(waitqueue_active(&li->wq));
 476        spin_unlock_bh(&li->lock);
 477        return 0;
 478}
 479
 480int kvm_s390_inject_vm(struct kvm *kvm,
 481                       struct kvm_s390_interrupt *s390int)
 482{
 483        struct kvm_s390_local_interrupt *li;
 484        struct kvm_s390_float_interrupt *fi;
 485        struct kvm_s390_interrupt_info *inti;
 486        int sigcpu;
 487
 488        inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 489        if (!inti)
 490                return -ENOMEM;
 491
 492        switch (s390int->type) {
 493        case KVM_S390_INT_VIRTIO:
 494                VM_EVENT(kvm, 5, "inject: virtio parm:%x,parm64:%lx",
 495                         s390int->parm, s390int->parm64);
 496                inti->type = s390int->type;
 497                inti->ext.ext_params = s390int->parm;
 498                inti->ext.ext_params2 = s390int->parm64;
 499                break;
 500        case KVM_S390_INT_SERVICE:
 501                VM_EVENT(kvm, 5, "inject: sclp parm:%x", s390int->parm);
 502                inti->type = s390int->type;
 503                inti->ext.ext_params = s390int->parm;
 504                break;
 505        case KVM_S390_PROGRAM_INT:
 506        case KVM_S390_SIGP_STOP:
 507        case KVM_S390_INT_EMERGENCY:
 508        default:
 509                kfree(inti);
 510                return -EINVAL;
 511        }
 512
 513        mutex_lock(&kvm->lock);
 514        fi = &kvm->arch.float_int;
 515        spin_lock_bh(&fi->lock);
 516        list_add_tail(&inti->list, &fi->list);
 517        atomic_set(&fi->active, 1);
 518        sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS);
 519        if (sigcpu == KVM_MAX_VCPUS) {
 520                do {
 521                        sigcpu = fi->next_rr_cpu++;
 522                        if (sigcpu == KVM_MAX_VCPUS)
 523                                sigcpu = fi->next_rr_cpu = 0;
 524                } while (fi->local_int[sigcpu] == NULL);
 525        }
 526        li = fi->local_int[sigcpu];
 527        spin_lock_bh(&li->lock);
 528        atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 529        if (waitqueue_active(&li->wq))
 530                wake_up_interruptible(&li->wq);
 531        spin_unlock_bh(&li->lock);
 532        spin_unlock_bh(&fi->lock);
 533        mutex_unlock(&kvm->lock);
 534        return 0;
 535}
 536
 537int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
 538                         struct kvm_s390_interrupt *s390int)
 539{
 540        struct kvm_s390_local_interrupt *li;
 541        struct kvm_s390_interrupt_info *inti;
 542
 543        inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 544        if (!inti)
 545                return -ENOMEM;
 546
 547        switch (s390int->type) {
 548        case KVM_S390_PROGRAM_INT:
 549                if (s390int->parm & 0xffff0000) {
 550                        kfree(inti);
 551                        return -EINVAL;
 552                }
 553                inti->type = s390int->type;
 554                inti->pgm.code = s390int->parm;
 555                VCPU_EVENT(vcpu, 3, "inject: program check %d (from user)",
 556                           s390int->parm);
 557                break;
 558        case KVM_S390_SIGP_STOP:
 559        case KVM_S390_RESTART:
 560        case KVM_S390_SIGP_SET_PREFIX:
 561        case KVM_S390_INT_EMERGENCY:
 562                VCPU_EVENT(vcpu, 3, "inject: type %x", s390int->type);
 563                inti->type = s390int->type;
 564                break;
 565        case KVM_S390_INT_VIRTIO:
 566        case KVM_S390_INT_SERVICE:
 567        default:
 568                kfree(inti);
 569                return -EINVAL;
 570        }
 571
 572        mutex_lock(&vcpu->kvm->lock);
 573        li = &vcpu->arch.local_int;
 574        spin_lock_bh(&li->lock);
 575        if (inti->type == KVM_S390_PROGRAM_INT)
 576                list_add(&inti->list, &li->list);
 577        else
 578                list_add_tail(&inti->list, &li->list);
 579        atomic_set(&li->active, 1);
 580        if (inti->type == KVM_S390_SIGP_STOP)
 581                li->action_bits |= ACTION_STOP_ON_STOP;
 582        atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 583        if (waitqueue_active(&li->wq))
 584                wake_up_interruptible(&vcpu->arch.local_int.wq);
 585        spin_unlock_bh(&li->lock);
 586        mutex_unlock(&vcpu->kvm->lock);
 587        return 0;
 588}
 589