1 /*- 2 * Copyright (c) 2003 Peter Wemm. 3 * Copyright (c) 1992 Terrence R. Lambert. 4 * Copyright (c) 1982, 1987, 1990 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * William Jolitz. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * from: @(#)machdep.c 7.4 (Berkeley) 6/3/91 39 */ 40 41 #include <sys/cdefs.h> 42 #include "opt_acpi.h" 43 #include "opt_atpic.h" 44 #include "opt_cpu.h" 45 #include "opt_ddb.h" 46 #include "opt_inet.h" 47 #include "opt_isa.h" 48 #include "opt_kdb.h" 49 #include "opt_kstack_pages.h" 50 #include "opt_maxmem.h" 51 #include "opt_platform.h" 52 #include "opt_sched.h" 53 #ifdef __i386__ 54 #include "opt_apic.h" 55 #endif 56 57 #include <sys/param.h> 58 #include <sys/proc.h> 59 #include <sys/systm.h> 60 #include <sys/bus.h> 61 #include <sys/cpu.h> 62 #include <sys/domainset.h> 63 #include <sys/kdb.h> 64 #include <sys/kernel.h> 65 #include <sys/ktr.h> 66 #include <sys/lock.h> 67 #include <sys/malloc.h> 68 #include <sys/mutex.h> 69 #include <sys/pcpu.h> 70 #include <sys/rwlock.h> 71 #include <sys/sched.h> 72 #include <sys/smp.h> 73 #include <sys/sysctl.h> 74 75 #include <machine/clock.h> 76 #include <machine/cpu.h> 77 #include <machine/cpufunc.h> 78 #include <machine/cputypes.h> 79 #include <machine/specialreg.h> 80 #include <machine/md_var.h> 81 #include <machine/tss.h> 82 #ifdef SMP 83 #include <machine/smp.h> 84 #endif 85 #ifdef CPU_ELAN 86 #include <machine/elan_mmcr.h> 87 #endif 88 #include <x86/acpica_machdep.h> 89 #include <x86/ifunc.h> 90 91 #include <vm/vm.h> 92 #include <vm/vm_extern.h> 93 #include <vm/vm_kern.h> 94 #include <vm/vm_page.h> 95 #include <vm/vm_map.h> 96 #include <vm/vm_object.h> 97 #include <vm/vm_pager.h> 98 #include <vm/vm_param.h> 99 100 #include <isa/isareg.h> 101 102 #include <contrib/dev/acpica/include/acpi.h> 103 104 #define STATE_RUNNING 0x0 105 #define STATE_MWAIT 0x1 106 #define STATE_SLEEPING 0x2 107 108 #ifdef SMP 109 static u_int cpu_reset_proxyid; 110 static volatile u_int cpu_reset_proxy_active; 111 #endif 112 113 char bootmethod[16]; 114 SYSCTL_STRING(_machdep, OID_AUTO, bootmethod, CTLFLAG_RD, bootmethod, 0, 115 "System firmware boot method"); 116 117 struct msr_op_arg { 118 u_int msr; 119 int op; 120 uint64_t arg1; 121 uint64_t *res; 122 }; 123 124 static void 125 x86_msr_op_one(void *argp) 126 { 127 struct msr_op_arg *a; 128 uint64_t v; 129 130 a = argp; 131 switch (a->op) { 132 case MSR_OP_ANDNOT: 133 v = rdmsr(a->msr); 134 v &= ~a->arg1; 135 wrmsr(a->msr, v); 136 break; 137 case MSR_OP_OR: 138 v = rdmsr(a->msr); 139 v |= a->arg1; 140 wrmsr(a->msr, v); 141 break; 142 case MSR_OP_WRITE: 143 wrmsr(a->msr, a->arg1); 144 break; 145 case MSR_OP_READ: 146 v = rdmsr(a->msr); 147 *a->res = v; 148 break; 149 } 150 } 151 152 #define MSR_OP_EXMODE_MASK 0xf0000000 153 #define MSR_OP_OP_MASK 0x000000ff 154 #define MSR_OP_GET_CPUID(x) (((x) & ~MSR_OP_EXMODE_MASK) >> 8) 155 156 void 157 x86_msr_op(u_int msr, u_int op, uint64_t arg1, uint64_t *res) 158 { 159 struct thread *td; 160 struct msr_op_arg a; 161 cpuset_t set; 162 u_int exmode; 163 int bound_cpu, cpu, i, is_bound; 164 165 a.op = op & MSR_OP_OP_MASK; 166 MPASS(a.op == MSR_OP_ANDNOT || a.op == MSR_OP_OR || 167 a.op == MSR_OP_WRITE || a.op == MSR_OP_READ); 168 exmode = op & MSR_OP_EXMODE_MASK; 169 MPASS(exmode == MSR_OP_LOCAL || exmode == MSR_OP_SCHED_ALL || 170 exmode == MSR_OP_SCHED_ONE || exmode == MSR_OP_RENDEZVOUS_ALL || 171 exmode == MSR_OP_RENDEZVOUS_ONE); 172 a.msr = msr; 173 a.arg1 = arg1; 174 a.res = res; 175 switch (exmode) { 176 case MSR_OP_LOCAL: 177 x86_msr_op_one(&a); 178 break; 179 case MSR_OP_SCHED_ALL: 180 td = curthread; 181 thread_lock(td); 182 is_bound = sched_is_bound(td); 183 bound_cpu = td->td_oncpu; 184 CPU_FOREACH(i) { 185 sched_bind(td, i); 186 x86_msr_op_one(&a); 187 } 188 if (is_bound) 189 sched_bind(td, bound_cpu); 190 else 191 sched_unbind(td); 192 thread_unlock(td); 193 break; 194 case MSR_OP_SCHED_ONE: 195 td = curthread; 196 cpu = MSR_OP_GET_CPUID(op); 197 thread_lock(td); 198 is_bound = sched_is_bound(td); 199 bound_cpu = td->td_oncpu; 200 if (!is_bound || bound_cpu != cpu) 201 sched_bind(td, cpu); 202 x86_msr_op_one(&a); 203 if (is_bound) { 204 if (bound_cpu != cpu) 205 sched_bind(td, bound_cpu); 206 } else { 207 sched_unbind(td); 208 } 209 thread_unlock(td); 210 break; 211 case MSR_OP_RENDEZVOUS_ALL: 212 smp_rendezvous(smp_no_rendezvous_barrier, x86_msr_op_one, 213 smp_no_rendezvous_barrier, &a); 214 break; 215 case MSR_OP_RENDEZVOUS_ONE: 216 cpu = MSR_OP_GET_CPUID(op); 217 CPU_SETOF(cpu, &set); 218 smp_rendezvous_cpus(set, smp_no_rendezvous_barrier, 219 x86_msr_op_one, smp_no_rendezvous_barrier, &a); 220 break; 221 } 222 } 223 224 /* 225 * Automatically initialized per CPU errata in cpu_idle_tun below. 226 */ 227 bool mwait_cpustop_broken = false; 228 SYSCTL_BOOL(_machdep, OID_AUTO, mwait_cpustop_broken, CTLFLAG_RDTUN, 229 &mwait_cpustop_broken, 0, 230 "Can not reliably wake MONITOR/MWAIT cpus without interrupts"); 231 232 /* 233 * Flush the D-cache for non-DMA I/O so that the I-cache can 234 * be made coherent later. 235 */ 236 void 237 cpu_flush_dcache(void *ptr, size_t len) 238 { 239 /* Not applicable */ 240 } 241 242 void 243 acpi_cpu_c1(void) 244 { 245 246 __asm __volatile("sti; hlt"); 247 } 248 249 /* 250 * Use mwait to pause execution while waiting for an interrupt or 251 * another thread to signal that there is more work. 252 * 253 * NOTE: Interrupts will cause a wakeup; however, this function does 254 * not enable interrupt handling. The caller is responsible to enable 255 * interrupts. 256 */ 257 void 258 acpi_cpu_idle_mwait(uint32_t mwait_hint) 259 { 260 int *state; 261 uint64_t v; 262 263 /* 264 * A comment in Linux patch claims that 'CPUs run faster with 265 * speculation protection disabled. All CPU threads in a core 266 * must disable speculation protection for it to be 267 * disabled. Disable it while we are idle so the other 268 * hyperthread can run fast.' 269 * 270 * XXXKIB. Software coordination mode should be supported, 271 * but all Intel CPUs provide hardware coordination. 272 */ 273 274 state = &PCPU_PTR(monitorbuf)->idle_state; 275 KASSERT(atomic_load_int(state) == STATE_SLEEPING, 276 ("cpu_mwait_cx: wrong monitorbuf state")); 277 atomic_store_int(state, STATE_MWAIT); 278 if (PCPU_GET(ibpb_set) || hw_ssb_active) { 279 v = rdmsr(MSR_IA32_SPEC_CTRL); 280 wrmsr(MSR_IA32_SPEC_CTRL, v & ~(IA32_SPEC_CTRL_IBRS | 281 IA32_SPEC_CTRL_STIBP | IA32_SPEC_CTRL_SSBD)); 282 } else { 283 v = 0; 284 } 285 cpu_monitor(state, 0, 0); 286 if (atomic_load_int(state) == STATE_MWAIT) 287 cpu_mwait(MWAIT_INTRBREAK, mwait_hint); 288 289 /* 290 * SSB cannot be disabled while we sleep, or rather, if it was 291 * disabled, the sysctl thread will bind to our cpu to tweak 292 * MSR. 293 */ 294 if (v != 0) 295 wrmsr(MSR_IA32_SPEC_CTRL, v); 296 297 /* 298 * We should exit on any event that interrupts mwait, because 299 * that event might be a wanted interrupt. 300 */ 301 atomic_store_int(state, STATE_RUNNING); 302 } 303 304 /* Get current clock frequency for the given cpu id. */ 305 int 306 cpu_est_clockrate(int cpu_id, uint64_t *rate) 307 { 308 uint64_t tsc1, tsc2; 309 uint64_t acnt, mcnt, perf; 310 register_t reg; 311 312 if (pcpu_find(cpu_id) == NULL || rate == NULL) 313 return (EINVAL); 314 #ifdef __i386__ 315 if ((cpu_feature & CPUID_TSC) == 0) 316 return (EOPNOTSUPP); 317 #endif 318 319 /* 320 * If TSC is P-state invariant and APERF/MPERF MSRs do not exist, 321 * DELAY(9) based logic fails. 322 */ 323 if (tsc_is_invariant && !tsc_perf_stat) 324 return (EOPNOTSUPP); 325 326 #ifdef SMP 327 if (smp_cpus > 1) { 328 /* Schedule ourselves on the indicated cpu. */ 329 thread_lock(curthread); 330 sched_bind(curthread, cpu_id); 331 thread_unlock(curthread); 332 } 333 #endif 334 335 /* Calibrate by measuring a short delay. */ 336 reg = intr_disable(); 337 if (tsc_is_invariant) { 338 wrmsr(MSR_MPERF, 0); 339 wrmsr(MSR_APERF, 0); 340 tsc1 = rdtsc(); 341 DELAY(1000); 342 mcnt = rdmsr(MSR_MPERF); 343 acnt = rdmsr(MSR_APERF); 344 tsc2 = rdtsc(); 345 intr_restore(reg); 346 perf = 1000 * acnt / mcnt; 347 *rate = (tsc2 - tsc1) * perf; 348 } else { 349 tsc1 = rdtsc(); 350 DELAY(1000); 351 tsc2 = rdtsc(); 352 intr_restore(reg); 353 *rate = (tsc2 - tsc1) * 1000; 354 } 355 356 #ifdef SMP 357 if (smp_cpus > 1) { 358 thread_lock(curthread); 359 sched_unbind(curthread); 360 thread_unlock(curthread); 361 } 362 #endif 363 364 return (0); 365 } 366 367 /* 368 * Shutdown the CPU as much as possible 369 */ 370 void 371 cpu_halt(void) 372 { 373 for (;;) 374 halt(); 375 } 376 377 static void 378 cpu_reset_real(void) 379 { 380 struct region_descriptor null_idt; 381 int b; 382 383 disable_intr(); 384 #ifdef CPU_ELAN 385 if (elan_mmcr != NULL) 386 elan_mmcr->RESCFG = 1; 387 #endif 388 #ifdef __i386__ 389 if (cpu == CPU_GEODE1100) { 390 /* Attempt Geode's own reset */ 391 outl(0xcf8, 0x80009044ul); 392 outl(0xcfc, 0xf); 393 } 394 #endif 395 #if !defined(BROKEN_KEYBOARD_RESET) 396 /* 397 * Attempt to do a CPU reset via the keyboard controller, 398 * do not turn off GateA20, as any machine that fails 399 * to do the reset here would then end up in no man's land. 400 */ 401 outb(IO_KBD + 4, 0xFE); 402 DELAY(500000); /* wait 0.5 sec to see if that did it */ 403 #endif 404 405 /* 406 * Attempt to force a reset via the Reset Control register at 407 * I/O port 0xcf9. Bit 2 forces a system reset when it 408 * transitions from 0 to 1. Bit 1 selects the type of reset 409 * to attempt: 0 selects a "soft" reset, and 1 selects a 410 * "hard" reset. We try a "hard" reset. The first write sets 411 * bit 1 to select a "hard" reset and clears bit 2. The 412 * second write forces a 0 -> 1 transition in bit 2 to trigger 413 * a reset. 414 */ 415 outb(0xcf9, 0x2); 416 outb(0xcf9, 0x6); 417 DELAY(500000); /* wait 0.5 sec to see if that did it */ 418 419 /* 420 * Attempt to force a reset via the Fast A20 and Init register 421 * at I/O port 0x92. Bit 1 serves as an alternate A20 gate. 422 * Bit 0 asserts INIT# when set to 1. We are careful to only 423 * preserve bit 1 while setting bit 0. We also must clear bit 424 * 0 before setting it if it isn't already clear. 425 */ 426 b = inb(0x92); 427 if (b != 0xff) { 428 if ((b & 0x1) != 0) 429 outb(0x92, b & 0xfe); 430 outb(0x92, b | 0x1); 431 DELAY(500000); /* wait 0.5 sec to see if that did it */ 432 } 433 434 printf("No known reset method worked, attempting CPU shutdown\n"); 435 DELAY(1000000); /* wait 1 sec for printf to complete */ 436 437 /* Wipe the IDT. */ 438 null_idt.rd_limit = 0; 439 null_idt.rd_base = 0; 440 lidt(&null_idt); 441 442 /* "good night, sweet prince .... <THUNK!>" */ 443 breakpoint(); 444 445 /* NOTREACHED */ 446 while(1); 447 } 448 449 #ifdef SMP 450 static void 451 cpu_reset_proxy(void) 452 { 453 454 cpu_reset_proxy_active = 1; 455 while (cpu_reset_proxy_active == 1) 456 ia32_pause(); /* Wait for other cpu to see that we've started */ 457 458 printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid); 459 DELAY(1000000); 460 cpu_reset_real(); 461 } 462 #endif 463 464 void 465 cpu_reset(void) 466 { 467 #ifdef SMP 468 struct monitorbuf *mb; 469 cpuset_t map; 470 u_int cnt; 471 472 if (smp_started) { 473 map = all_cpus; 474 CPU_CLR(PCPU_GET(cpuid), &map); 475 CPU_ANDNOT(&map, &map, &stopped_cpus); 476 if (!CPU_EMPTY(&map)) { 477 printf("cpu_reset: Stopping other CPUs\n"); 478 stop_cpus(map); 479 } 480 481 if (PCPU_GET(cpuid) != 0) { 482 cpu_reset_proxyid = PCPU_GET(cpuid); 483 cpustop_restartfunc = cpu_reset_proxy; 484 cpu_reset_proxy_active = 0; 485 printf("cpu_reset: Restarting BSP\n"); 486 487 /* Restart CPU #0. */ 488 CPU_SETOF(0, &started_cpus); 489 mb = &pcpu_find(0)->pc_monitorbuf; 490 atomic_store_int(&mb->stop_state, 491 MONITOR_STOPSTATE_RUNNING); 492 493 cnt = 0; 494 while (cpu_reset_proxy_active == 0 && cnt < 10000000) { 495 ia32_pause(); 496 cnt++; /* Wait for BSP to announce restart */ 497 } 498 if (cpu_reset_proxy_active == 0) { 499 printf("cpu_reset: Failed to restart BSP\n"); 500 } else { 501 cpu_reset_proxy_active = 2; 502 while (1) 503 ia32_pause(); 504 /* NOTREACHED */ 505 } 506 } 507 } 508 #endif 509 cpu_reset_real(); 510 /* NOTREACHED */ 511 } 512 513 bool 514 cpu_mwait_usable(void) 515 { 516 517 return ((cpu_feature2 & CPUID2_MON) != 0 && ((cpu_mon_mwait_flags & 518 (CPUID5_MON_MWAIT_EXT | CPUID5_MWAIT_INTRBREAK)) == 519 (CPUID5_MON_MWAIT_EXT | CPUID5_MWAIT_INTRBREAK))); 520 } 521 522 void (*cpu_idle_hook)(sbintime_t) = NULL; /* ACPI idle hook. */ 523 524 int cpu_amdc1e_bug = 0; /* AMD C1E APIC workaround required. */ 525 526 static int idle_mwait = 1; /* Use MONITOR/MWAIT for short idle. */ 527 SYSCTL_INT(_machdep, OID_AUTO, idle_mwait, CTLFLAG_RWTUN, &idle_mwait, 528 0, "Use MONITOR/MWAIT for short idle"); 529 530 static bool 531 cpu_idle_enter(int *statep, int newstate) 532 { 533 KASSERT(atomic_load_int(statep) == STATE_RUNNING, 534 ("%s: state %d", __func__, atomic_load_int(statep))); 535 536 /* 537 * A fence is needed to prevent reordering of the load in 538 * sched_runnable() with this store to the idle state word. Without it, 539 * cpu_idle_wakeup() can observe the state as STATE_RUNNING after having 540 * added load to the queue, and elide an IPI. Then, sched_runnable() 541 * can observe tdq_load == 0, so the CPU ends up idling with pending 542 * work. tdq_notify() similarly ensures that a prior update to tdq_load 543 * is visible before calling cpu_idle_wakeup(). 544 */ 545 atomic_store_int(statep, newstate); 546 #if defined(SCHED_ULE) && defined(SMP) 547 atomic_thread_fence_seq_cst(); 548 #endif 549 550 /* 551 * Since we may be in a critical section from cpu_idle(), if 552 * an interrupt fires during that critical section we may have 553 * a pending preemption. If the CPU halts, then that thread 554 * may not execute until a later interrupt awakens the CPU. 555 * To handle this race, check for a runnable thread after 556 * disabling interrupts and immediately return if one is 557 * found. Also, we must absolutely guarentee that hlt is 558 * the next instruction after sti. This ensures that any 559 * interrupt that fires after the call to disable_intr() will 560 * immediately awaken the CPU from hlt. Finally, please note 561 * that on x86 this works fine because of interrupts enabled only 562 * after the instruction following sti takes place, while IF is set 563 * to 1 immediately, allowing hlt instruction to acknowledge the 564 * interrupt. 565 */ 566 disable_intr(); 567 if (sched_runnable()) { 568 enable_intr(); 569 atomic_store_int(statep, STATE_RUNNING); 570 return (false); 571 } else { 572 return (true); 573 } 574 } 575 576 static void 577 cpu_idle_exit(int *statep) 578 { 579 atomic_store_int(statep, STATE_RUNNING); 580 } 581 582 static void 583 cpu_idle_acpi(sbintime_t sbt) 584 { 585 int *state; 586 587 state = &PCPU_PTR(monitorbuf)->idle_state; 588 if (cpu_idle_enter(state, STATE_SLEEPING)) { 589 if (cpu_idle_hook) 590 cpu_idle_hook(sbt); 591 else 592 acpi_cpu_c1(); 593 cpu_idle_exit(state); 594 } 595 } 596 597 static void 598 cpu_idle_hlt(sbintime_t sbt) 599 { 600 int *state; 601 602 state = &PCPU_PTR(monitorbuf)->idle_state; 603 if (cpu_idle_enter(state, STATE_SLEEPING)) { 604 acpi_cpu_c1(); 605 atomic_store_int(state, STATE_RUNNING); 606 } 607 } 608 609 static void 610 cpu_idle_mwait(sbintime_t sbt) 611 { 612 int *state; 613 614 state = &PCPU_PTR(monitorbuf)->idle_state; 615 if (cpu_idle_enter(state, STATE_MWAIT)) { 616 cpu_monitor(state, 0, 0); 617 if (atomic_load_int(state) == STATE_MWAIT) 618 __asm __volatile("sti; mwait" : : "a" (MWAIT_C1), "c" (0)); 619 else 620 enable_intr(); 621 cpu_idle_exit(state); 622 } 623 } 624 625 static void 626 cpu_idle_spin(sbintime_t sbt) 627 { 628 int *state; 629 int i; 630 631 state = &PCPU_PTR(monitorbuf)->idle_state; 632 atomic_store_int(state, STATE_RUNNING); 633 634 /* 635 * The sched_runnable() call is racy but as long as there is 636 * a loop missing it one time will have just a little impact if any 637 * (and it is much better than missing the check at all). 638 */ 639 for (i = 0; i < 1000; i++) { 640 if (sched_runnable()) 641 return; 642 cpu_spinwait(); 643 } 644 } 645 646 void (*cpu_idle_fn)(sbintime_t) = cpu_idle_acpi; 647 648 void 649 cpu_idle(int busy) 650 { 651 uint64_t msr; 652 sbintime_t sbt = -1; 653 654 CTR1(KTR_SPARE2, "cpu_idle(%d)", busy); 655 656 /* If we are busy - try to use fast methods. */ 657 if (busy) { 658 if ((cpu_feature2 & CPUID2_MON) && idle_mwait) { 659 cpu_idle_mwait(busy); 660 goto out; 661 } 662 } 663 664 /* If we have time - switch timers into idle mode. */ 665 if (!busy) { 666 critical_enter(); 667 sbt = cpu_idleclock(); 668 } 669 670 /* Apply AMD APIC timer C1E workaround. */ 671 if (cpu_amdc1e_bug && cpu_disable_c3_sleep) { 672 msr = rdmsr(MSR_AMDK8_IPM); 673 if ((msr & (AMDK8_SMIONCMPHALT | AMDK8_C1EONCMPHALT)) != 0) 674 wrmsr(MSR_AMDK8_IPM, msr & ~(AMDK8_SMIONCMPHALT | 675 AMDK8_C1EONCMPHALT)); 676 } 677 678 /* Call main idle method. */ 679 cpu_idle_fn(sbt); 680 681 /* Switch timers back into active mode. */ 682 if (!busy) { 683 cpu_activeclock(); 684 critical_exit(); 685 } 686 out: 687 CTR1(KTR_SPARE2, "cpu_idle(%d) done", busy); 688 } 689 690 static int cpu_idle_apl31_workaround; 691 SYSCTL_INT(_machdep, OID_AUTO, idle_apl31, CTLFLAG_RWTUN | CTLFLAG_NOFETCH, 692 &cpu_idle_apl31_workaround, 0, 693 "Apollo Lake APL31 MWAIT bug workaround"); 694 695 int 696 cpu_idle_wakeup(int cpu) 697 { 698 struct monitorbuf *mb; 699 int *state; 700 701 mb = &pcpu_find(cpu)->pc_monitorbuf; 702 state = &mb->idle_state; 703 switch (atomic_load_int(state)) { 704 case STATE_SLEEPING: 705 return (0); 706 case STATE_MWAIT: 707 atomic_store_int(state, STATE_RUNNING); 708 return (cpu_idle_apl31_workaround ? 0 : 1); 709 case STATE_RUNNING: 710 return (1); 711 default: 712 panic("bad monitor state"); 713 return (1); 714 } 715 } 716 717 /* 718 * Ordered by speed/power consumption. 719 */ 720 static const struct { 721 void *id_fn; 722 const char *id_name; 723 int id_cpuid2_flag; 724 } idle_tbl[] = { 725 { .id_fn = cpu_idle_spin, .id_name = "spin" }, 726 { .id_fn = cpu_idle_mwait, .id_name = "mwait", 727 .id_cpuid2_flag = CPUID2_MON }, 728 { .id_fn = cpu_idle_hlt, .id_name = "hlt" }, 729 { .id_fn = cpu_idle_acpi, .id_name = "acpi" }, 730 }; 731 732 static int 733 idle_sysctl_available(SYSCTL_HANDLER_ARGS) 734 { 735 char *avail, *p; 736 int error; 737 int i; 738 739 avail = malloc(256, M_TEMP, M_WAITOK); 740 p = avail; 741 for (i = 0; i < nitems(idle_tbl); i++) { 742 if (idle_tbl[i].id_cpuid2_flag != 0 && 743 (cpu_feature2 & idle_tbl[i].id_cpuid2_flag) == 0) 744 continue; 745 if (strcmp(idle_tbl[i].id_name, "acpi") == 0 && 746 cpu_idle_hook == NULL) 747 continue; 748 p += sprintf(p, "%s%s", p != avail ? ", " : "", 749 idle_tbl[i].id_name); 750 } 751 error = sysctl_handle_string(oidp, avail, 0, req); 752 free(avail, M_TEMP); 753 return (error); 754 } 755 756 SYSCTL_PROC(_machdep, OID_AUTO, idle_available, 757 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 758 0, 0, idle_sysctl_available, "A", 759 "list of available idle functions"); 760 761 static bool 762 cpu_idle_selector(const char *new_idle_name) 763 { 764 int i; 765 766 for (i = 0; i < nitems(idle_tbl); i++) { 767 if (idle_tbl[i].id_cpuid2_flag != 0 && 768 (cpu_feature2 & idle_tbl[i].id_cpuid2_flag) == 0) 769 continue; 770 if (strcmp(idle_tbl[i].id_name, "acpi") == 0 && 771 cpu_idle_hook == NULL) 772 continue; 773 if (strcmp(idle_tbl[i].id_name, new_idle_name)) 774 continue; 775 cpu_idle_fn = idle_tbl[i].id_fn; 776 if (bootverbose) 777 printf("CPU idle set to %s\n", idle_tbl[i].id_name); 778 return (true); 779 } 780 return (false); 781 } 782 783 static int 784 cpu_idle_sysctl(SYSCTL_HANDLER_ARGS) 785 { 786 char buf[16]; 787 const char *p; 788 int error, i; 789 790 p = "unknown"; 791 for (i = 0; i < nitems(idle_tbl); i++) { 792 if (idle_tbl[i].id_fn == cpu_idle_fn) { 793 p = idle_tbl[i].id_name; 794 break; 795 } 796 } 797 strncpy(buf, p, sizeof(buf)); 798 error = sysctl_handle_string(oidp, buf, sizeof(buf), req); 799 if (error != 0 || req->newptr == NULL) 800 return (error); 801 return (cpu_idle_selector(buf) ? 0 : EINVAL); 802 } 803 804 SYSCTL_PROC(_machdep, OID_AUTO, idle, 805 CTLTYPE_STRING | CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, 806 0, 0, cpu_idle_sysctl, "A", 807 "currently selected idle function"); 808 809 static void 810 cpu_idle_tun(void *unused __unused) 811 { 812 char tunvar[16]; 813 814 if (TUNABLE_STR_FETCH("machdep.idle", tunvar, sizeof(tunvar))) 815 cpu_idle_selector(tunvar); 816 else if (cpu_vendor_id == CPU_VENDOR_AMD && 817 CPUID_TO_FAMILY(cpu_id) == 0x17 && CPUID_TO_MODEL(cpu_id) == 0x1) { 818 /* Ryzen erratas 1057, 1109. */ 819 cpu_idle_selector("hlt"); 820 idle_mwait = 0; 821 mwait_cpustop_broken = true; 822 } 823 824 if (cpu_vendor_id == CPU_VENDOR_INTEL && 825 CPUID_TO_FAMILY(cpu_id) == 0x6 && CPUID_TO_MODEL(cpu_id) == 0x5c) { 826 /* 827 * Apollo Lake errata APL31 (public errata APL30). 828 * Stores to the armed address range may not trigger 829 * MWAIT to resume execution. OS needs to use 830 * interrupts to wake processors from MWAIT-induced 831 * sleep states. 832 */ 833 cpu_idle_apl31_workaround = 1; 834 mwait_cpustop_broken = true; 835 } 836 TUNABLE_INT_FETCH("machdep.idle_apl31", &cpu_idle_apl31_workaround); 837 } 838 SYSINIT(cpu_idle_tun, SI_SUB_CPU, SI_ORDER_MIDDLE, cpu_idle_tun, NULL); 839 840 static int panic_on_nmi = 0xff; 841 SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RWTUN, 842 &panic_on_nmi, 0, 843 "Panic on NMI: 1 = H/W failure; 2 = unknown; 0xff = all"); 844 int nmi_is_broadcast = 1; 845 SYSCTL_INT(_machdep, OID_AUTO, nmi_is_broadcast, CTLFLAG_RWTUN, 846 &nmi_is_broadcast, 0, 847 "Chipset NMI is broadcast"); 848 int (*apei_nmi)(void); 849 850 void 851 nmi_call_kdb(u_int cpu, u_int type, struct trapframe *frame) 852 { 853 bool claimed = false; 854 855 #ifdef DEV_ISA 856 /* machine/parity/power fail/"kitchen sink" faults */ 857 if (isa_nmi(frame->tf_err)) { 858 claimed = true; 859 if ((panic_on_nmi & 1) != 0) 860 panic("NMI indicates hardware failure"); 861 } 862 #endif /* DEV_ISA */ 863 864 /* ACPI Platform Error Interfaces callback. */ 865 if (apei_nmi != NULL && (*apei_nmi)()) 866 claimed = true; 867 868 /* 869 * NMIs can be useful for debugging. They can be hooked up to a 870 * pushbutton, usually on an ISA, PCI, or PCIe card. They can also be 871 * generated by an IPMI BMC, either manually or in response to a 872 * watchdog timeout. For example, see the "power diag" command in 873 * ports/sysutils/ipmitool. They can also be generated by a 874 * hypervisor; see "bhyvectl --inject-nmi". 875 */ 876 877 #ifdef KDB 878 if (!claimed && (panic_on_nmi & 2) != 0) { 879 if (debugger_on_panic) { 880 printf("NMI/cpu%d ... going to debugger\n", cpu); 881 claimed = kdb_trap(type, 0, frame); 882 } 883 } 884 #endif /* KDB */ 885 886 if (!claimed && panic_on_nmi != 0) 887 panic("NMI"); 888 } 889 890 void 891 nmi_handle_intr(u_int type, struct trapframe *frame) 892 { 893 894 #ifdef SMP 895 if (nmi_is_broadcast) { 896 nmi_call_kdb_smp(type, frame); 897 return; 898 } 899 #endif 900 nmi_call_kdb(PCPU_GET(cpuid), type, frame); 901 } 902 903 static int hw_ibrs_active; 904 int hw_ibrs_ibpb_active; 905 int hw_ibrs_disable = 1; 906 907 SYSCTL_INT(_hw, OID_AUTO, ibrs_active, CTLFLAG_RD, &hw_ibrs_active, 0, 908 "Indirect Branch Restricted Speculation active"); 909 910 SYSCTL_NODE(_machdep_mitigations, OID_AUTO, ibrs, 911 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 912 "Indirect Branch Restricted Speculation active"); 913 914 SYSCTL_INT(_machdep_mitigations_ibrs, OID_AUTO, active, CTLFLAG_RD, 915 &hw_ibrs_active, 0, "Indirect Branch Restricted Speculation active"); 916 917 void 918 hw_ibrs_recalculate(bool for_all_cpus) 919 { 920 if ((cpu_ia32_arch_caps & IA32_ARCH_CAP_IBRS_ALL) != 0) { 921 x86_msr_op(MSR_IA32_SPEC_CTRL, (for_all_cpus ? 922 MSR_OP_RENDEZVOUS_ALL : MSR_OP_LOCAL) | 923 (hw_ibrs_disable != 0 ? MSR_OP_ANDNOT : MSR_OP_OR), 924 IA32_SPEC_CTRL_IBRS, NULL); 925 hw_ibrs_active = hw_ibrs_disable == 0; 926 hw_ibrs_ibpb_active = 0; 927 } else { 928 hw_ibrs_active = hw_ibrs_ibpb_active = (cpu_stdext_feature3 & 929 CPUID_STDEXT3_IBPB) != 0 && !hw_ibrs_disable; 930 } 931 } 932 933 static int 934 hw_ibrs_disable_handler(SYSCTL_HANDLER_ARGS) 935 { 936 int error, val; 937 938 val = hw_ibrs_disable; 939 error = sysctl_handle_int(oidp, &val, 0, req); 940 if (error != 0 || req->newptr == NULL) 941 return (error); 942 hw_ibrs_disable = val != 0; 943 hw_ibrs_recalculate(true); 944 return (0); 945 } 946 SYSCTL_PROC(_hw, OID_AUTO, ibrs_disable, CTLTYPE_INT | CTLFLAG_RWTUN | 947 CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, NULL, 0, hw_ibrs_disable_handler, "I", 948 "Disable Indirect Branch Restricted Speculation"); 949 950 SYSCTL_PROC(_machdep_mitigations_ibrs, OID_AUTO, disable, CTLTYPE_INT | 951 CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, NULL, 0, 952 hw_ibrs_disable_handler, "I", 953 "Disable Indirect Branch Restricted Speculation"); 954 955 int hw_ssb_active; 956 int hw_ssb_disable; 957 958 SYSCTL_INT(_hw, OID_AUTO, spec_store_bypass_disable_active, CTLFLAG_RD, 959 &hw_ssb_active, 0, 960 "Speculative Store Bypass Disable active"); 961 962 SYSCTL_NODE(_machdep_mitigations, OID_AUTO, ssb, 963 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 964 "Speculative Store Bypass Disable active"); 965 966 SYSCTL_INT(_machdep_mitigations_ssb, OID_AUTO, active, CTLFLAG_RD, 967 &hw_ssb_active, 0, "Speculative Store Bypass Disable active"); 968 969 static void 970 hw_ssb_set(bool enable, bool for_all_cpus) 971 { 972 973 if ((cpu_stdext_feature3 & CPUID_STDEXT3_SSBD) == 0) { 974 hw_ssb_active = 0; 975 return; 976 } 977 hw_ssb_active = enable; 978 x86_msr_op(MSR_IA32_SPEC_CTRL, 979 (enable ? MSR_OP_OR : MSR_OP_ANDNOT) | 980 (for_all_cpus ? MSR_OP_SCHED_ALL : MSR_OP_LOCAL), 981 IA32_SPEC_CTRL_SSBD, NULL); 982 } 983 984 void 985 hw_ssb_recalculate(bool all_cpus) 986 { 987 988 switch (hw_ssb_disable) { 989 default: 990 hw_ssb_disable = 0; 991 /* FALLTHROUGH */ 992 case 0: /* off */ 993 hw_ssb_set(false, all_cpus); 994 break; 995 case 1: /* on */ 996 hw_ssb_set(true, all_cpus); 997 break; 998 case 2: /* auto */ 999 hw_ssb_set((cpu_ia32_arch_caps & IA32_ARCH_CAP_SSB_NO) != 0 ? 1000 false : true, all_cpus); 1001 break; 1002 } 1003 } 1004 1005 static int 1006 hw_ssb_disable_handler(SYSCTL_HANDLER_ARGS) 1007 { 1008 int error, val; 1009 1010 val = hw_ssb_disable; 1011 error = sysctl_handle_int(oidp, &val, 0, req); 1012 if (error != 0 || req->newptr == NULL) 1013 return (error); 1014 hw_ssb_disable = val; 1015 hw_ssb_recalculate(true); 1016 return (0); 1017 } 1018 SYSCTL_PROC(_hw, OID_AUTO, spec_store_bypass_disable, CTLTYPE_INT | 1019 CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, NULL, 0, 1020 hw_ssb_disable_handler, "I", 1021 "Speculative Store Bypass Disable (0 - off, 1 - on, 2 - auto)"); 1022 1023 SYSCTL_PROC(_machdep_mitigations_ssb, OID_AUTO, disable, CTLTYPE_INT | 1024 CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, NULL, 0, 1025 hw_ssb_disable_handler, "I", 1026 "Speculative Store Bypass Disable (0 - off, 1 - on, 2 - auto)"); 1027 1028 int hw_mds_disable; 1029 1030 /* 1031 * Handler for Microarchitectural Data Sampling issues. Really not a 1032 * pointer to C function: on amd64 the code must not change any CPU 1033 * architectural state except possibly %rflags. Also, it is always 1034 * called with interrupts disabled. 1035 */ 1036 void mds_handler_void(void); 1037 void mds_handler_verw(void); 1038 void mds_handler_ivb(void); 1039 void mds_handler_bdw(void); 1040 void mds_handler_skl_sse(void); 1041 void mds_handler_skl_avx(void); 1042 void mds_handler_skl_avx512(void); 1043 void mds_handler_silvermont(void); 1044 void (*mds_handler)(void) = mds_handler_void; 1045 1046 static int 1047 sysctl_hw_mds_disable_state_handler(SYSCTL_HANDLER_ARGS) 1048 { 1049 const char *state; 1050 1051 if (mds_handler == mds_handler_void) 1052 state = "inactive"; 1053 else if (mds_handler == mds_handler_verw) 1054 state = "VERW"; 1055 else if (mds_handler == mds_handler_ivb) 1056 state = "software IvyBridge"; 1057 else if (mds_handler == mds_handler_bdw) 1058 state = "software Broadwell"; 1059 else if (mds_handler == mds_handler_skl_sse) 1060 state = "software Skylake SSE"; 1061 else if (mds_handler == mds_handler_skl_avx) 1062 state = "software Skylake AVX"; 1063 else if (mds_handler == mds_handler_skl_avx512) 1064 state = "software Skylake AVX512"; 1065 else if (mds_handler == mds_handler_silvermont) 1066 state = "software Silvermont"; 1067 else 1068 state = "unknown"; 1069 return (SYSCTL_OUT(req, state, strlen(state))); 1070 } 1071 1072 SYSCTL_PROC(_hw, OID_AUTO, mds_disable_state, 1073 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 1074 sysctl_hw_mds_disable_state_handler, "A", 1075 "Microarchitectural Data Sampling Mitigation state"); 1076 1077 SYSCTL_NODE(_machdep_mitigations, OID_AUTO, mds, 1078 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1079 "Microarchitectural Data Sampling Mitigation state"); 1080 1081 SYSCTL_PROC(_machdep_mitigations_mds, OID_AUTO, state, 1082 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 1083 sysctl_hw_mds_disable_state_handler, "A", 1084 "Microarchitectural Data Sampling Mitigation state"); 1085 1086 _Static_assert(__offsetof(struct pcpu, pc_mds_tmp) % 64 == 0, "MDS AVX512"); 1087 1088 void 1089 hw_mds_recalculate(void) 1090 { 1091 struct pcpu *pc; 1092 vm_offset_t b64; 1093 u_long xcr0; 1094 int i; 1095 1096 /* 1097 * Allow user to force VERW variant even if MD_CLEAR is not 1098 * reported. For instance, hypervisor might unknowingly 1099 * filter the cap out. 1100 * For the similar reasons, and for testing, allow to enable 1101 * mitigation even when MDS_NO cap is set. 1102 */ 1103 if (cpu_vendor_id != CPU_VENDOR_INTEL || hw_mds_disable == 0 || 1104 ((cpu_ia32_arch_caps & IA32_ARCH_CAP_MDS_NO) != 0 && 1105 hw_mds_disable == 3)) { 1106 mds_handler = mds_handler_void; 1107 } else if (((cpu_stdext_feature3 & CPUID_STDEXT3_MD_CLEAR) != 0 && 1108 hw_mds_disable == 3) || hw_mds_disable == 1) { 1109 mds_handler = mds_handler_verw; 1110 } else if (CPUID_TO_FAMILY(cpu_id) == 0x6 && 1111 (CPUID_TO_MODEL(cpu_id) == 0x2e || CPUID_TO_MODEL(cpu_id) == 0x1e || 1112 CPUID_TO_MODEL(cpu_id) == 0x1f || CPUID_TO_MODEL(cpu_id) == 0x1a || 1113 CPUID_TO_MODEL(cpu_id) == 0x2f || CPUID_TO_MODEL(cpu_id) == 0x25 || 1114 CPUID_TO_MODEL(cpu_id) == 0x2c || CPUID_TO_MODEL(cpu_id) == 0x2d || 1115 CPUID_TO_MODEL(cpu_id) == 0x2a || CPUID_TO_MODEL(cpu_id) == 0x3e || 1116 CPUID_TO_MODEL(cpu_id) == 0x3a) && 1117 (hw_mds_disable == 2 || hw_mds_disable == 3)) { 1118 /* 1119 * Nehalem, SandyBridge, IvyBridge 1120 */ 1121 CPU_FOREACH(i) { 1122 pc = pcpu_find(i); 1123 if (pc->pc_mds_buf == NULL) { 1124 pc->pc_mds_buf = malloc_domainset(672, M_TEMP, 1125 DOMAINSET_PREF(pc->pc_domain), M_WAITOK); 1126 bzero(pc->pc_mds_buf, 16); 1127 } 1128 } 1129 mds_handler = mds_handler_ivb; 1130 } else if (CPUID_TO_FAMILY(cpu_id) == 0x6 && 1131 (CPUID_TO_MODEL(cpu_id) == 0x3f || CPUID_TO_MODEL(cpu_id) == 0x3c || 1132 CPUID_TO_MODEL(cpu_id) == 0x45 || CPUID_TO_MODEL(cpu_id) == 0x46 || 1133 CPUID_TO_MODEL(cpu_id) == 0x56 || CPUID_TO_MODEL(cpu_id) == 0x4f || 1134 CPUID_TO_MODEL(cpu_id) == 0x47 || CPUID_TO_MODEL(cpu_id) == 0x3d) && 1135 (hw_mds_disable == 2 || hw_mds_disable == 3)) { 1136 /* 1137 * Haswell, Broadwell 1138 */ 1139 CPU_FOREACH(i) { 1140 pc = pcpu_find(i); 1141 if (pc->pc_mds_buf == NULL) { 1142 pc->pc_mds_buf = malloc_domainset(1536, M_TEMP, 1143 DOMAINSET_PREF(pc->pc_domain), M_WAITOK); 1144 bzero(pc->pc_mds_buf, 16); 1145 } 1146 } 1147 mds_handler = mds_handler_bdw; 1148 } else if (CPUID_TO_FAMILY(cpu_id) == 0x6 && 1149 ((CPUID_TO_MODEL(cpu_id) == 0x55 && (cpu_id & 1150 CPUID_STEPPING) <= 5) || 1151 CPUID_TO_MODEL(cpu_id) == 0x4e || CPUID_TO_MODEL(cpu_id) == 0x5e || 1152 (CPUID_TO_MODEL(cpu_id) == 0x8e && (cpu_id & 1153 CPUID_STEPPING) <= 0xb) || 1154 (CPUID_TO_MODEL(cpu_id) == 0x9e && (cpu_id & 1155 CPUID_STEPPING) <= 0xc)) && 1156 (hw_mds_disable == 2 || hw_mds_disable == 3)) { 1157 /* 1158 * Skylake, KabyLake, CoffeeLake, WhiskeyLake, 1159 * CascadeLake 1160 */ 1161 CPU_FOREACH(i) { 1162 pc = pcpu_find(i); 1163 if (pc->pc_mds_buf == NULL) { 1164 pc->pc_mds_buf = malloc_domainset(6 * 1024, 1165 M_TEMP, DOMAINSET_PREF(pc->pc_domain), 1166 M_WAITOK); 1167 b64 = (vm_offset_t)malloc_domainset(64 + 63, 1168 M_TEMP, DOMAINSET_PREF(pc->pc_domain), 1169 M_WAITOK); 1170 pc->pc_mds_buf64 = (void *)roundup2(b64, 64); 1171 bzero(pc->pc_mds_buf64, 64); 1172 } 1173 } 1174 xcr0 = rxcr(0); 1175 if ((xcr0 & XFEATURE_ENABLED_ZMM_HI256) != 0 && 1176 (cpu_stdext_feature & CPUID_STDEXT_AVX512DQ) != 0) 1177 mds_handler = mds_handler_skl_avx512; 1178 else if ((xcr0 & XFEATURE_ENABLED_AVX) != 0 && 1179 (cpu_feature2 & CPUID2_AVX) != 0) 1180 mds_handler = mds_handler_skl_avx; 1181 else 1182 mds_handler = mds_handler_skl_sse; 1183 } else if (CPUID_TO_FAMILY(cpu_id) == 0x6 && 1184 ((CPUID_TO_MODEL(cpu_id) == 0x37 || 1185 CPUID_TO_MODEL(cpu_id) == 0x4a || 1186 CPUID_TO_MODEL(cpu_id) == 0x4c || 1187 CPUID_TO_MODEL(cpu_id) == 0x4d || 1188 CPUID_TO_MODEL(cpu_id) == 0x5a || 1189 CPUID_TO_MODEL(cpu_id) == 0x5d || 1190 CPUID_TO_MODEL(cpu_id) == 0x6e || 1191 CPUID_TO_MODEL(cpu_id) == 0x65 || 1192 CPUID_TO_MODEL(cpu_id) == 0x75 || 1193 CPUID_TO_MODEL(cpu_id) == 0x1c || 1194 CPUID_TO_MODEL(cpu_id) == 0x26 || 1195 CPUID_TO_MODEL(cpu_id) == 0x27 || 1196 CPUID_TO_MODEL(cpu_id) == 0x35 || 1197 CPUID_TO_MODEL(cpu_id) == 0x36 || 1198 CPUID_TO_MODEL(cpu_id) == 0x7a))) { 1199 /* Silvermont, Airmont */ 1200 CPU_FOREACH(i) { 1201 pc = pcpu_find(i); 1202 if (pc->pc_mds_buf == NULL) 1203 pc->pc_mds_buf = malloc(256, M_TEMP, M_WAITOK); 1204 } 1205 mds_handler = mds_handler_silvermont; 1206 } else { 1207 hw_mds_disable = 0; 1208 mds_handler = mds_handler_void; 1209 } 1210 } 1211 1212 static void 1213 hw_mds_recalculate_boot(void *arg __unused) 1214 { 1215 1216 hw_mds_recalculate(); 1217 } 1218 SYSINIT(mds_recalc, SI_SUB_SMP, SI_ORDER_ANY, hw_mds_recalculate_boot, NULL); 1219 1220 static int 1221 sysctl_mds_disable_handler(SYSCTL_HANDLER_ARGS) 1222 { 1223 int error, val; 1224 1225 val = hw_mds_disable; 1226 error = sysctl_handle_int(oidp, &val, 0, req); 1227 if (error != 0 || req->newptr == NULL) 1228 return (error); 1229 if (val < 0 || val > 3) 1230 return (EINVAL); 1231 hw_mds_disable = val; 1232 hw_mds_recalculate(); 1233 return (0); 1234 } 1235 1236 SYSCTL_PROC(_hw, OID_AUTO, mds_disable, CTLTYPE_INT | 1237 CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, NULL, 0, 1238 sysctl_mds_disable_handler, "I", 1239 "Microarchitectural Data Sampling Mitigation " 1240 "(0 - off, 1 - on VERW, 2 - on SW, 3 - on AUTO)"); 1241 1242 SYSCTL_PROC(_machdep_mitigations_mds, OID_AUTO, disable, CTLTYPE_INT | 1243 CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, NULL, 0, 1244 sysctl_mds_disable_handler, "I", 1245 "Microarchitectural Data Sampling Mitigation " 1246 "(0 - off, 1 - on VERW, 2 - on SW, 3 - on AUTO)"); 1247 1248 /* 1249 * Intel Transactional Memory Asynchronous Abort Mitigation 1250 * CVE-2019-11135 1251 */ 1252 int x86_taa_enable; 1253 int x86_taa_state; 1254 enum { 1255 TAA_NONE = 0, /* No mitigation enabled */ 1256 TAA_TSX_DISABLE = 1, /* Disable TSX via MSR */ 1257 TAA_VERW = 2, /* Use VERW mitigation */ 1258 TAA_AUTO = 3, /* Automatically select the mitigation */ 1259 1260 /* The states below are not selectable by the operator */ 1261 1262 TAA_TAA_UC = 4, /* Mitigation present in microcode */ 1263 TAA_NOT_PRESENT = 5 /* TSX is not present */ 1264 }; 1265 1266 static void 1267 taa_set(bool enable, bool all) 1268 { 1269 1270 x86_msr_op(MSR_IA32_TSX_CTRL, 1271 (enable ? MSR_OP_OR : MSR_OP_ANDNOT) | 1272 (all ? MSR_OP_RENDEZVOUS_ALL : MSR_OP_LOCAL), 1273 IA32_TSX_CTRL_RTM_DISABLE | IA32_TSX_CTRL_TSX_CPUID_CLEAR, 1274 NULL); 1275 } 1276 1277 void 1278 x86_taa_recalculate(void) 1279 { 1280 static int taa_saved_mds_disable = 0; 1281 int taa_need = 0, taa_state = 0; 1282 int mds_disable = 0, need_mds_recalc = 0; 1283 1284 /* Check CPUID.07h.EBX.HLE and RTM for the presence of TSX */ 1285 if ((cpu_stdext_feature & CPUID_STDEXT_HLE) == 0 || 1286 (cpu_stdext_feature & CPUID_STDEXT_RTM) == 0) { 1287 /* TSX is not present */ 1288 x86_taa_state = TAA_NOT_PRESENT; 1289 return; 1290 } 1291 1292 /* Check to see what mitigation options the CPU gives us */ 1293 if (cpu_ia32_arch_caps & IA32_ARCH_CAP_TAA_NO) { 1294 /* CPU is not suseptible to TAA */ 1295 taa_need = TAA_TAA_UC; 1296 } else if (cpu_ia32_arch_caps & IA32_ARCH_CAP_TSX_CTRL) { 1297 /* 1298 * CPU can turn off TSX. This is the next best option 1299 * if TAA_NO hardware mitigation isn't present 1300 */ 1301 taa_need = TAA_TSX_DISABLE; 1302 } else { 1303 /* No TSX/TAA specific remedies are available. */ 1304 if (x86_taa_enable == TAA_TSX_DISABLE) { 1305 if (bootverbose) 1306 printf("TSX control not available\n"); 1307 return; 1308 } else 1309 taa_need = TAA_VERW; 1310 } 1311 1312 /* Can we automatically take action, or are we being forced? */ 1313 if (x86_taa_enable == TAA_AUTO) 1314 taa_state = taa_need; 1315 else 1316 taa_state = x86_taa_enable; 1317 1318 /* No state change, nothing to do */ 1319 if (taa_state == x86_taa_state) { 1320 if (bootverbose) 1321 printf("No TSX change made\n"); 1322 return; 1323 } 1324 1325 /* Does the MSR need to be turned on or off? */ 1326 if (taa_state == TAA_TSX_DISABLE) 1327 taa_set(true, true); 1328 else if (x86_taa_state == TAA_TSX_DISABLE) 1329 taa_set(false, true); 1330 1331 /* Does MDS need to be set to turn on VERW? */ 1332 if (taa_state == TAA_VERW) { 1333 taa_saved_mds_disable = hw_mds_disable; 1334 mds_disable = hw_mds_disable = 1; 1335 need_mds_recalc = 1; 1336 } else if (x86_taa_state == TAA_VERW) { 1337 mds_disable = hw_mds_disable = taa_saved_mds_disable; 1338 need_mds_recalc = 1; 1339 } 1340 if (need_mds_recalc) { 1341 hw_mds_recalculate(); 1342 if (mds_disable != hw_mds_disable) { 1343 if (bootverbose) 1344 printf("Cannot change MDS state for TAA\n"); 1345 /* Don't update our state */ 1346 return; 1347 } 1348 } 1349 1350 x86_taa_state = taa_state; 1351 return; 1352 } 1353 1354 static void 1355 taa_recalculate_boot(void * arg __unused) 1356 { 1357 1358 x86_taa_recalculate(); 1359 } 1360 SYSINIT(taa_recalc, SI_SUB_SMP, SI_ORDER_ANY, taa_recalculate_boot, NULL); 1361 1362 SYSCTL_NODE(_machdep_mitigations, OID_AUTO, taa, 1363 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1364 "TSX Asynchronous Abort Mitigation"); 1365 1366 static int 1367 sysctl_taa_handler(SYSCTL_HANDLER_ARGS) 1368 { 1369 int error, val; 1370 1371 val = x86_taa_enable; 1372 error = sysctl_handle_int(oidp, &val, 0, req); 1373 if (error != 0 || req->newptr == NULL) 1374 return (error); 1375 if (val < TAA_NONE || val > TAA_AUTO) 1376 return (EINVAL); 1377 x86_taa_enable = val; 1378 x86_taa_recalculate(); 1379 return (0); 1380 } 1381 1382 SYSCTL_PROC(_machdep_mitigations_taa, OID_AUTO, enable, CTLTYPE_INT | 1383 CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, NULL, 0, 1384 sysctl_taa_handler, "I", 1385 "TAA Mitigation enablement control " 1386 "(0 - off, 1 - disable TSX, 2 - VERW, 3 - on AUTO)"); 1387 1388 static int 1389 sysctl_taa_state_handler(SYSCTL_HANDLER_ARGS) 1390 { 1391 const char *state; 1392 1393 switch (x86_taa_state) { 1394 case TAA_NONE: 1395 state = "inactive"; 1396 break; 1397 case TAA_TSX_DISABLE: 1398 state = "TSX disabled"; 1399 break; 1400 case TAA_VERW: 1401 state = "VERW"; 1402 break; 1403 case TAA_TAA_UC: 1404 state = "Mitigated in microcode"; 1405 break; 1406 case TAA_NOT_PRESENT: 1407 state = "TSX not present"; 1408 break; 1409 default: 1410 state = "unknown"; 1411 } 1412 1413 return (SYSCTL_OUT(req, state, strlen(state))); 1414 } 1415 1416 SYSCTL_PROC(_machdep_mitigations_taa, OID_AUTO, state, 1417 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 1418 sysctl_taa_state_handler, "A", 1419 "TAA Mitigation state"); 1420 1421 int __read_frequently cpu_flush_rsb_ctxsw; 1422 SYSCTL_INT(_machdep_mitigations, OID_AUTO, flush_rsb_ctxsw, 1423 CTLFLAG_RW | CTLFLAG_NOFETCH, &cpu_flush_rsb_ctxsw, 0, 1424 "Flush Return Stack Buffer on context switch"); 1425 1426 SYSCTL_NODE(_machdep_mitigations, OID_AUTO, rngds, 1427 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1428 "MCU Optimization, disable RDSEED mitigation"); 1429 1430 int x86_rngds_mitg_enable = 1; 1431 void 1432 x86_rngds_mitg_recalculate(bool all_cpus) 1433 { 1434 if ((cpu_stdext_feature3 & CPUID_STDEXT3_MCUOPT) == 0) 1435 return; 1436 x86_msr_op(MSR_IA32_MCU_OPT_CTRL, 1437 (x86_rngds_mitg_enable ? MSR_OP_OR : MSR_OP_ANDNOT) | 1438 (all_cpus ? MSR_OP_RENDEZVOUS_ALL : MSR_OP_LOCAL), 1439 IA32_RNGDS_MITG_DIS, NULL); 1440 } 1441 1442 static int 1443 sysctl_rngds_mitg_enable_handler(SYSCTL_HANDLER_ARGS) 1444 { 1445 int error, val; 1446 1447 val = x86_rngds_mitg_enable; 1448 error = sysctl_handle_int(oidp, &val, 0, req); 1449 if (error != 0 || req->newptr == NULL) 1450 return (error); 1451 x86_rngds_mitg_enable = val; 1452 x86_rngds_mitg_recalculate(true); 1453 return (0); 1454 } 1455 SYSCTL_PROC(_machdep_mitigations_rngds, OID_AUTO, enable, CTLTYPE_INT | 1456 CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, NULL, 0, 1457 sysctl_rngds_mitg_enable_handler, "I", 1458 "MCU Optimization, disabling RDSEED mitigation control " 1459 "(0 - mitigation disabled (RDSEED optimized), 1 - mitigation enabled)"); 1460 1461 static int 1462 sysctl_rngds_state_handler(SYSCTL_HANDLER_ARGS) 1463 { 1464 const char *state; 1465 1466 if ((cpu_stdext_feature3 & CPUID_STDEXT3_MCUOPT) == 0) { 1467 state = "Not applicable"; 1468 } else if (x86_rngds_mitg_enable == 0) { 1469 state = "RDSEED not serialized"; 1470 } else { 1471 state = "Mitigated"; 1472 } 1473 return (SYSCTL_OUT(req, state, strlen(state))); 1474 } 1475 SYSCTL_PROC(_machdep_mitigations_rngds, OID_AUTO, state, 1476 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 1477 sysctl_rngds_state_handler, "A", 1478 "MCU Optimization state"); 1479 1480 1481 /* 1482 * Zenbleed. 1483 * 1484 * No corresponding errata is publicly listed. AMD has issued a security 1485 * bulletin (AMD-SB-7008), entitled "Cross-Process Information Leak". This 1486 * document lists (as of August 2023) platform firmware's availability target 1487 * dates, with most being November/December 2023. It will then be up to 1488 * motherboard manufacturers to produce corresponding BIOS updates, which will 1489 * happen with an inevitable lag. Additionally, for a variety of reasons, 1490 * operators might not be able to apply them everywhere due. On the side of 1491 * standalone CPU microcodes, no plans for availability have been published so 1492 * far. However, a developer appearing to be an AMD employee has hardcoded in 1493 * Linux revision numbers of future microcodes that are presumed to fix the 1494 * vulnerability. 1495 * 1496 * Given the stability issues encountered with early microcode releases for Rome 1497 * (the only microcode publicly released so far) and the absence of official 1498 * communication on standalone CPU microcodes, we have opted instead for 1499 * matching by default all AMD Zen2 processors which, according to the 1500 * vulnerability's discoverer, are all affected (see 1501 * https://lock.cmpxchg8b.com/zenbleed.html). This policy, also adopted by 1502 * OpenBSD, may be overriden using the tunable/sysctl 1503 * 'machdep.mitigations.zenbleed.enable'. We might revise it later depending on 1504 * official statements, microcode updates' public availability and community 1505 * assessment that they actually fix the vulnerability without any instability 1506 * side effects. 1507 */ 1508 1509 SYSCTL_NODE(_machdep_mitigations, OID_AUTO, zenbleed, 1510 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 1511 "Zenbleed OS-triggered prevention (via chicken bit)"); 1512 1513 /* 2 is auto, see below. */ 1514 int zenbleed_enable = 2; 1515 1516 void 1517 zenbleed_sanitize_enable(void) 1518 { 1519 /* Default to auto (2). */ 1520 if (zenbleed_enable < 0 || zenbleed_enable > 2) 1521 zenbleed_enable = 2; 1522 } 1523 1524 static bool 1525 zenbleed_chicken_bit_applicable(void) 1526 { 1527 /* Concerns only bare-metal AMD Zen2 processors. */ 1528 return (cpu_vendor_id == CPU_VENDOR_AMD && 1529 CPUID_TO_FAMILY(cpu_id) == 0x17 && 1530 CPUID_TO_MODEL(cpu_id) >= 0x30 && 1531 vm_guest == VM_GUEST_NO); 1532 } 1533 1534 static bool 1535 zenbleed_chicken_bit_should_enable(void) 1536 { 1537 /* 1538 * Obey tunable/sysctl. 1539 * 1540 * As explained above, currently, the automatic setting (2) and the "on" 1541 * one (1) have the same effect. In the future, we might additionally 1542 * check for specific microcode revisions as part of the automatic 1543 * determination. 1544 */ 1545 return (zenbleed_enable != 0); 1546 } 1547 1548 void 1549 zenbleed_check_and_apply(bool all_cpus) 1550 { 1551 bool set; 1552 1553 if (!zenbleed_chicken_bit_applicable()) 1554 return; 1555 1556 set = zenbleed_chicken_bit_should_enable(); 1557 1558 x86_msr_op(MSR_DE_CFG, 1559 (set ? MSR_OP_OR : MSR_OP_ANDNOT) | 1560 (all_cpus ? MSR_OP_RENDEZVOUS_ALL : MSR_OP_LOCAL), 1561 DE_CFG_ZEN2_FP_BACKUP_FIX_BIT, NULL); 1562 } 1563 1564 static int 1565 sysctl_zenbleed_enable_handler(SYSCTL_HANDLER_ARGS) 1566 { 1567 int error, val; 1568 1569 val = zenbleed_enable; 1570 error = sysctl_handle_int(oidp, &val, 0, req); 1571 if (error != 0 || req->newptr == NULL) 1572 return (error); 1573 zenbleed_enable = val; 1574 zenbleed_sanitize_enable(); 1575 zenbleed_check_and_apply(true); 1576 return (0); 1577 } 1578 SYSCTL_PROC(_machdep_mitigations_zenbleed, OID_AUTO, enable, CTLTYPE_INT | 1579 CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, NULL, 0, 1580 sysctl_zenbleed_enable_handler, "I", 1581 "Enable Zenbleed OS-triggered mitigation (chicken bit) " 1582 "(0: Force disable, 1: Force enable, 2: Automatic determination)"); 1583 1584 static int 1585 sysctl_zenbleed_state_handler(SYSCTL_HANDLER_ARGS) 1586 { 1587 const char *state; 1588 1589 if (!zenbleed_chicken_bit_applicable()) 1590 state = "Not applicable"; 1591 else if (zenbleed_chicken_bit_should_enable()) 1592 state = "Mitigation enabled"; 1593 else 1594 state = "Mitigation disabled"; 1595 return (SYSCTL_OUT(req, state, strlen(state))); 1596 } 1597 SYSCTL_PROC(_machdep_mitigations_zenbleed, OID_AUTO, state, 1598 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 1599 sysctl_zenbleed_state_handler, "A", 1600 "Zenbleed OS-triggered mitigation (chicken bit) state"); 1601 1602 1603 /* 1604 * Enable and restore kernel text write permissions. 1605 * Callers must ensure that disable_wp()/restore_wp() are executed 1606 * without rescheduling on the same core. 1607 */ 1608 bool 1609 disable_wp(void) 1610 { 1611 u_int cr0; 1612 1613 cr0 = rcr0(); 1614 if ((cr0 & CR0_WP) == 0) 1615 return (false); 1616 load_cr0(cr0 & ~CR0_WP); 1617 return (true); 1618 } 1619 1620 void 1621 restore_wp(bool old_wp) 1622 { 1623 1624 if (old_wp) 1625 load_cr0(rcr0() | CR0_WP); 1626 } 1627 1628 bool 1629 acpi_get_fadt_bootflags(uint16_t *flagsp) 1630 { 1631 #ifdef DEV_ACPI 1632 ACPI_TABLE_FADT *fadt; 1633 vm_paddr_t physaddr; 1634 1635 physaddr = acpi_find_table(ACPI_SIG_FADT); 1636 if (physaddr == 0) 1637 return (false); 1638 fadt = acpi_map_table(physaddr, ACPI_SIG_FADT); 1639 if (fadt == NULL) 1640 return (false); 1641 *flagsp = fadt->BootFlags; 1642 acpi_unmap_table(fadt); 1643 return (true); 1644 #else 1645 return (false); 1646 #endif 1647 } 1648 1649 DEFINE_IFUNC(, uint64_t, rdtsc_ordered, (void)) 1650 { 1651 bool cpu_is_amd = cpu_vendor_id == CPU_VENDOR_AMD || 1652 cpu_vendor_id == CPU_VENDOR_HYGON; 1653 1654 if ((amd_feature & AMDID_RDTSCP) != 0) 1655 return (rdtscp); 1656 else if ((cpu_feature & CPUID_SSE2) != 0) 1657 return (cpu_is_amd ? rdtsc_ordered_mfence : 1658 rdtsc_ordered_lfence); 1659 else 1660 return (rdtsc); 1661 } 1662