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