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