1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * in-kernel handling for sie intercepts 4 * 5 * Copyright IBM Corp. 2008, 2014 6 * 7 * Author(s): Carsten Otte <cotte@de.ibm.com> 8 * Christian Borntraeger <borntraeger@de.ibm.com> 9 */ 10 11 #include <linux/kvm_host.h> 12 #include <linux/errno.h> 13 #include <linux/pagemap.h> 14 15 #include <asm/kvm_host.h> 16 #include <asm/asm-offsets.h> 17 #include <asm/irq.h> 18 #include <asm/sysinfo.h> 19 20 #include "kvm-s390.h" 21 #include "gaccess.h" 22 #include "trace.h" 23 #include "trace-s390.h" 24 25 u8 kvm_s390_get_ilen(struct kvm_vcpu *vcpu) 26 { 27 struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block; 28 u8 ilen = 0; 29 30 switch (vcpu->arch.sie_block->icptcode) { 31 case ICPT_INST: 32 case ICPT_INSTPROGI: 33 case ICPT_OPEREXC: 34 case ICPT_PARTEXEC: 35 case ICPT_IOINST: 36 /* instruction only stored for these icptcodes */ 37 ilen = insn_length(vcpu->arch.sie_block->ipa >> 8); 38 /* Use the length of the EXECUTE instruction if necessary */ 39 if (sie_block->icptstatus & 1) { 40 ilen = (sie_block->icptstatus >> 4) & 0x6; 41 if (!ilen) 42 ilen = 4; 43 } 44 break; 45 case ICPT_PROGI: 46 /* bit 1+2 of pgmilc are the ilc, so we directly get ilen */ 47 ilen = vcpu->arch.sie_block->pgmilc & 0x6; 48 break; 49 } 50 return ilen; 51 } 52 53 static int handle_noop(struct kvm_vcpu *vcpu) 54 { 55 switch (vcpu->arch.sie_block->icptcode) { 56 case 0x10: 57 vcpu->stat.exit_external_request++; 58 break; 59 default: 60 break; /* nothing */ 61 } 62 return 0; 63 } 64 65 static int handle_stop(struct kvm_vcpu *vcpu) 66 { 67 struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; 68 int rc = 0; 69 uint8_t flags, stop_pending; 70 71 vcpu->stat.exit_stop_request++; 72 73 /* delay the stop if any non-stop irq is pending */ 74 if (kvm_s390_vcpu_has_irq(vcpu, 1)) 75 return 0; 76 77 /* avoid races with the injection/SIGP STOP code */ 78 spin_lock(&li->lock); 79 flags = li->irq.stop.flags; 80 stop_pending = kvm_s390_is_stop_irq_pending(vcpu); 81 spin_unlock(&li->lock); 82 83 trace_kvm_s390_stop_request(stop_pending, flags); 84 if (!stop_pending) 85 return 0; 86 87 if (flags & KVM_S390_STOP_FLAG_STORE_STATUS) { 88 rc = kvm_s390_vcpu_store_status(vcpu, 89 KVM_S390_STORE_STATUS_NOADDR); 90 if (rc) 91 return rc; 92 } 93 94 if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) 95 kvm_s390_vcpu_stop(vcpu); 96 return -EOPNOTSUPP; 97 } 98 99 static int handle_validity(struct kvm_vcpu *vcpu) 100 { 101 int viwhy = vcpu->arch.sie_block->ipb >> 16; 102 103 vcpu->stat.exit_validity++; 104 trace_kvm_s390_intercept_validity(vcpu, viwhy); 105 KVM_EVENT(3, "validity intercept 0x%x for pid %u (kvm 0x%pK)", viwhy, 106 current->pid, vcpu->kvm); 107 108 /* do not warn on invalid runtime instrumentation mode */ 109 WARN_ONCE(viwhy != 0x44, "kvm: unhandled validity intercept 0x%x\n", 110 viwhy); 111 return -EINVAL; 112 } 113 114 static int handle_instruction(struct kvm_vcpu *vcpu) 115 { 116 vcpu->stat.exit_instruction++; 117 trace_kvm_s390_intercept_instruction(vcpu, 118 vcpu->arch.sie_block->ipa, 119 vcpu->arch.sie_block->ipb); 120 121 switch (vcpu->arch.sie_block->ipa >> 8) { 122 case 0x01: 123 return kvm_s390_handle_01(vcpu); 124 case 0x82: 125 return kvm_s390_handle_lpsw(vcpu); 126 case 0x83: 127 return kvm_s390_handle_diag(vcpu); 128 case 0xaa: 129 return kvm_s390_handle_aa(vcpu); 130 case 0xae: 131 return kvm_s390_handle_sigp(vcpu); 132 case 0xb2: 133 return kvm_s390_handle_b2(vcpu); 134 case 0xb6: 135 return kvm_s390_handle_stctl(vcpu); 136 case 0xb7: 137 return kvm_s390_handle_lctl(vcpu); 138 case 0xb9: 139 return kvm_s390_handle_b9(vcpu); 140 case 0xe3: 141 return kvm_s390_handle_e3(vcpu); 142 case 0xe5: 143 return kvm_s390_handle_e5(vcpu); 144 case 0xeb: 145 return kvm_s390_handle_eb(vcpu); 146 default: 147 return -EOPNOTSUPP; 148 } 149 } 150 151 static int inject_prog_on_prog_intercept(struct kvm_vcpu *vcpu) 152 { 153 struct kvm_s390_pgm_info pgm_info = { 154 .code = vcpu->arch.sie_block->iprcc, 155 /* the PSW has already been rewound */ 156 .flags = KVM_S390_PGM_FLAGS_NO_REWIND, 157 }; 158 159 switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) { 160 case PGM_AFX_TRANSLATION: 161 case PGM_ASX_TRANSLATION: 162 case PGM_EX_TRANSLATION: 163 case PGM_LFX_TRANSLATION: 164 case PGM_LSTE_SEQUENCE: 165 case PGM_LSX_TRANSLATION: 166 case PGM_LX_TRANSLATION: 167 case PGM_PRIMARY_AUTHORITY: 168 case PGM_SECONDARY_AUTHORITY: 169 case PGM_SPACE_SWITCH: 170 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc; 171 break; 172 case PGM_ALEN_TRANSLATION: 173 case PGM_ALE_SEQUENCE: 174 case PGM_ASTE_INSTANCE: 175 case PGM_ASTE_SEQUENCE: 176 case PGM_ASTE_VALIDITY: 177 case PGM_EXTENDED_AUTHORITY: 178 pgm_info.exc_access_id = vcpu->arch.sie_block->eai; 179 break; 180 case PGM_ASCE_TYPE: 181 case PGM_PAGE_TRANSLATION: 182 case PGM_REGION_FIRST_TRANS: 183 case PGM_REGION_SECOND_TRANS: 184 case PGM_REGION_THIRD_TRANS: 185 case PGM_SEGMENT_TRANSLATION: 186 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc; 187 pgm_info.exc_access_id = vcpu->arch.sie_block->eai; 188 pgm_info.op_access_id = vcpu->arch.sie_block->oai; 189 break; 190 case PGM_MONITOR: 191 pgm_info.mon_class_nr = vcpu->arch.sie_block->mcn; 192 pgm_info.mon_code = vcpu->arch.sie_block->tecmc; 193 break; 194 case PGM_VECTOR_PROCESSING: 195 case PGM_DATA: 196 pgm_info.data_exc_code = vcpu->arch.sie_block->dxc; 197 break; 198 case PGM_PROTECTION: 199 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc; 200 pgm_info.exc_access_id = vcpu->arch.sie_block->eai; 201 break; 202 default: 203 break; 204 } 205 206 if (vcpu->arch.sie_block->iprcc & PGM_PER) { 207 pgm_info.per_code = vcpu->arch.sie_block->perc; 208 pgm_info.per_atmid = vcpu->arch.sie_block->peratmid; 209 pgm_info.per_address = vcpu->arch.sie_block->peraddr; 210 pgm_info.per_access_id = vcpu->arch.sie_block->peraid; 211 } 212 return kvm_s390_inject_prog_irq(vcpu, &pgm_info); 213 } 214 215 /* 216 * restore ITDB to program-interruption TDB in guest lowcore 217 * and set TX abort indication if required 218 */ 219 static int handle_itdb(struct kvm_vcpu *vcpu) 220 { 221 struct kvm_s390_itdb *itdb; 222 int rc; 223 224 if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu)) 225 return 0; 226 if (current->thread.per_flags & PER_FLAG_NO_TE) 227 return 0; 228 itdb = (struct kvm_s390_itdb *)vcpu->arch.sie_block->itdba; 229 rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb)); 230 if (rc) 231 return rc; 232 memset(itdb, 0, sizeof(*itdb)); 233 234 return 0; 235 } 236 237 #define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER) 238 239 static int handle_prog(struct kvm_vcpu *vcpu) 240 { 241 psw_t psw; 242 int rc; 243 244 vcpu->stat.exit_program_interruption++; 245 246 if (guestdbg_enabled(vcpu) && per_event(vcpu)) { 247 rc = kvm_s390_handle_per_event(vcpu); 248 if (rc) 249 return rc; 250 /* the interrupt might have been filtered out completely */ 251 if (vcpu->arch.sie_block->iprcc == 0) 252 return 0; 253 } 254 255 trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc); 256 if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) { 257 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t)); 258 if (rc) 259 return rc; 260 /* Avoid endless loops of specification exceptions */ 261 if (!is_valid_psw(&psw)) 262 return -EOPNOTSUPP; 263 } 264 rc = handle_itdb(vcpu); 265 if (rc) 266 return rc; 267 268 return inject_prog_on_prog_intercept(vcpu); 269 } 270 271 /** 272 * handle_external_interrupt - used for external interruption interceptions 273 * 274 * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if 275 * the new PSW does not have external interrupts disabled. In the first case, 276 * we've got to deliver the interrupt manually, and in the second case, we 277 * drop to userspace to handle the situation there. 278 */ 279 static int handle_external_interrupt(struct kvm_vcpu *vcpu) 280 { 281 u16 eic = vcpu->arch.sie_block->eic; 282 struct kvm_s390_irq irq; 283 psw_t newpsw; 284 int rc; 285 286 vcpu->stat.exit_external_interrupt++; 287 288 rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t)); 289 if (rc) 290 return rc; 291 /* We can not handle clock comparator or timer interrupt with bad PSW */ 292 if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) && 293 (newpsw.mask & PSW_MASK_EXT)) 294 return -EOPNOTSUPP; 295 296 switch (eic) { 297 case EXT_IRQ_CLK_COMP: 298 irq.type = KVM_S390_INT_CLOCK_COMP; 299 break; 300 case EXT_IRQ_CPU_TIMER: 301 irq.type = KVM_S390_INT_CPU_TIMER; 302 break; 303 case EXT_IRQ_EXTERNAL_CALL: 304 irq.type = KVM_S390_INT_EXTERNAL_CALL; 305 irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr; 306 rc = kvm_s390_inject_vcpu(vcpu, &irq); 307 /* ignore if another external call is already pending */ 308 if (rc == -EBUSY) 309 return 0; 310 return rc; 311 default: 312 return -EOPNOTSUPP; 313 } 314 315 return kvm_s390_inject_vcpu(vcpu, &irq); 316 } 317 318 /** 319 * Handle MOVE PAGE partial execution interception. 320 * 321 * This interception can only happen for guests with DAT disabled and 322 * addresses that are currently not mapped in the host. Thus we try to 323 * set up the mappings for the corresponding user pages here (or throw 324 * addressing exceptions in case of illegal guest addresses). 325 */ 326 static int handle_mvpg_pei(struct kvm_vcpu *vcpu) 327 { 328 unsigned long srcaddr, dstaddr; 329 int reg1, reg2, rc; 330 331 kvm_s390_get_regs_rre(vcpu, ®1, ®2); 332 333 /* Make sure that the source is paged-in */ 334 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg2], 335 reg2, &srcaddr, GACC_FETCH); 336 if (rc) 337 return kvm_s390_inject_prog_cond(vcpu, rc); 338 rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0); 339 if (rc != 0) 340 return rc; 341 342 /* Make sure that the destination is paged-in */ 343 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg1], 344 reg1, &dstaddr, GACC_STORE); 345 if (rc) 346 return kvm_s390_inject_prog_cond(vcpu, rc); 347 rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1); 348 if (rc != 0) 349 return rc; 350 351 kvm_s390_retry_instr(vcpu); 352 353 return 0; 354 } 355 356 static int handle_partial_execution(struct kvm_vcpu *vcpu) 357 { 358 vcpu->stat.exit_pei++; 359 360 if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */ 361 return handle_mvpg_pei(vcpu); 362 if (vcpu->arch.sie_block->ipa >> 8 == 0xae) /* SIGP */ 363 return kvm_s390_handle_sigp_pei(vcpu); 364 365 return -EOPNOTSUPP; 366 } 367 368 /* 369 * Handle the sthyi instruction that provides the guest with system 370 * information, like current CPU resources available at each level of 371 * the machine. 372 */ 373 int handle_sthyi(struct kvm_vcpu *vcpu) 374 { 375 int reg1, reg2, r = 0; 376 u64 code, addr, cc = 0, rc = 0; 377 struct sthyi_sctns *sctns = NULL; 378 379 if (!test_kvm_facility(vcpu->kvm, 74)) 380 return kvm_s390_inject_program_int(vcpu, PGM_OPERATION); 381 382 kvm_s390_get_regs_rre(vcpu, ®1, ®2); 383 code = vcpu->run->s.regs.gprs[reg1]; 384 addr = vcpu->run->s.regs.gprs[reg2]; 385 386 vcpu->stat.instruction_sthyi++; 387 VCPU_EVENT(vcpu, 3, "STHYI: fc: %llu addr: 0x%016llx", code, addr); 388 trace_kvm_s390_handle_sthyi(vcpu, code, addr); 389 390 if (reg1 == reg2 || reg1 & 1 || reg2 & 1) 391 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); 392 393 if (code & 0xffff) { 394 cc = 3; 395 rc = 4; 396 goto out; 397 } 398 399 if (addr & ~PAGE_MASK) 400 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); 401 402 sctns = (void *)get_zeroed_page(GFP_KERNEL); 403 if (!sctns) 404 return -ENOMEM; 405 406 cc = sthyi_fill(sctns, &rc); 407 408 out: 409 if (!cc) { 410 r = write_guest(vcpu, addr, reg2, sctns, PAGE_SIZE); 411 if (r) { 412 free_page((unsigned long)sctns); 413 return kvm_s390_inject_prog_cond(vcpu, r); 414 } 415 } 416 417 free_page((unsigned long)sctns); 418 vcpu->run->s.regs.gprs[reg2 + 1] = rc; 419 kvm_s390_set_psw_cc(vcpu, cc); 420 return r; 421 } 422 423 static int handle_operexc(struct kvm_vcpu *vcpu) 424 { 425 psw_t oldpsw, newpsw; 426 int rc; 427 428 vcpu->stat.exit_operation_exception++; 429 trace_kvm_s390_handle_operexc(vcpu, vcpu->arch.sie_block->ipa, 430 vcpu->arch.sie_block->ipb); 431 432 if (vcpu->arch.sie_block->ipa == 0xb256) 433 return handle_sthyi(vcpu); 434 435 if (vcpu->arch.sie_block->ipa == 0 && vcpu->kvm->arch.user_instr0) 436 return -EOPNOTSUPP; 437 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &newpsw, sizeof(psw_t)); 438 if (rc) 439 return rc; 440 /* 441 * Avoid endless loops of operation exceptions, if the pgm new 442 * PSW will cause a new operation exception. 443 * The heuristic checks if the pgm new psw is within 6 bytes before 444 * the faulting psw address (with same DAT, AS settings) and the 445 * new psw is not a wait psw and the fault was not triggered by 446 * problem state. 447 */ 448 oldpsw = vcpu->arch.sie_block->gpsw; 449 if (oldpsw.addr - newpsw.addr <= 6 && 450 !(newpsw.mask & PSW_MASK_WAIT) && 451 !(oldpsw.mask & PSW_MASK_PSTATE) && 452 (newpsw.mask & PSW_MASK_ASC) == (oldpsw.mask & PSW_MASK_ASC) && 453 (newpsw.mask & PSW_MASK_DAT) == (oldpsw.mask & PSW_MASK_DAT)) 454 return -EOPNOTSUPP; 455 456 return kvm_s390_inject_program_int(vcpu, PGM_OPERATION); 457 } 458 459 int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu) 460 { 461 int rc, per_rc = 0; 462 463 if (kvm_is_ucontrol(vcpu->kvm)) 464 return -EOPNOTSUPP; 465 466 switch (vcpu->arch.sie_block->icptcode) { 467 case ICPT_EXTREQ: 468 case ICPT_IOREQ: 469 return handle_noop(vcpu); 470 case ICPT_INST: 471 rc = handle_instruction(vcpu); 472 break; 473 case ICPT_PROGI: 474 return handle_prog(vcpu); 475 case ICPT_EXTINT: 476 return handle_external_interrupt(vcpu); 477 case ICPT_WAIT: 478 return kvm_s390_handle_wait(vcpu); 479 case ICPT_VALIDITY: 480 return handle_validity(vcpu); 481 case ICPT_STOP: 482 return handle_stop(vcpu); 483 case ICPT_OPEREXC: 484 rc = handle_operexc(vcpu); 485 break; 486 case ICPT_PARTEXEC: 487 rc = handle_partial_execution(vcpu); 488 break; 489 case ICPT_KSS: 490 rc = kvm_s390_skey_check_enable(vcpu); 491 break; 492 default: 493 return -EOPNOTSUPP; 494 } 495 496 /* process PER, also if the instrution is processed in user space */ 497 if (vcpu->arch.sie_block->icptstatus & 0x02 && 498 (!rc || rc == -EOPNOTSUPP)) 499 per_rc = kvm_s390_handle_per_ifetch_icpt(vcpu); 500 return per_rc ? per_rc : rc; 501 } 502