1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24 /*
25 * Copyright (c) 2010, Intel Corporation.
26 * All rights reserved.
27 */
28 /*
29 * Copyright 2011 Joyent, Inc. All rights reserved.
30 */
31
32 /*
33 * Welcome to the world of the "real mode platter".
34 * See also startup.c, mpcore.s and apic.c for related routines.
35 */
36
37 #include <sys/types.h>
38 #include <sys/systm.h>
39 #include <sys/cpuvar.h>
40 #include <sys/cpu_module.h>
41 #include <sys/kmem.h>
42 #include <sys/archsystm.h>
43 #include <sys/machsystm.h>
44 #include <sys/controlregs.h>
45 #include <sys/x86_archext.h>
46 #include <sys/smp_impldefs.h>
47 #include <sys/sysmacros.h>
48 #include <sys/mach_mmu.h>
49 #include <sys/promif.h>
50 #include <sys/cpu.h>
51 #include <sys/cpu_event.h>
52 #include <sys/sunndi.h>
53 #include <sys/fs/dv_node.h>
54 #include <vm/hat_i86.h>
55 #include <vm/as.h>
56
57 extern cpuset_t cpu_ready_set;
58
59 extern int mp_start_cpu_common(cpu_t *cp, boolean_t boot);
60 extern void real_mode_start_cpu(void);
61 extern void real_mode_start_cpu_end(void);
62 extern void real_mode_stop_cpu_stage1(void);
63 extern void real_mode_stop_cpu_stage1_end(void);
64 extern void real_mode_stop_cpu_stage2(void);
65 extern void real_mode_stop_cpu_stage2_end(void);
66
67 void rmp_gdt_init(rm_platter_t *);
68
69 /*
70 * Fill up the real mode platter to make it easy for real mode code to
71 * kick it off. This area should really be one passed by boot to kernel
72 * and guaranteed to be below 1MB and aligned to 16 bytes. Should also
73 * have identical physical and virtual address in paged mode.
74 */
75 static ushort_t *warm_reset_vector = NULL;
76
77 int
mach_cpucontext_init(void)78 mach_cpucontext_init(void)
79 {
80 ushort_t *vec;
81 ulong_t addr;
82 struct rm_platter *rm = (struct rm_platter *)rm_platter_va;
83
84 if (!(vec = (ushort_t *)psm_map_phys(WARM_RESET_VECTOR,
85 sizeof (vec), PROT_READ | PROT_WRITE)))
86 return (-1);
87
88 /*
89 * setup secondary cpu bios boot up vector
90 * Write page offset to 0x467 and page frame number to 0x469.
91 */
92 addr = (ulong_t)((caddr_t)rm->rm_code - (caddr_t)rm) + rm_platter_pa;
93 vec[0] = (ushort_t)(addr & PAGEOFFSET);
94 vec[1] = (ushort_t)((addr & (0xfffff & PAGEMASK)) >> 4);
95 warm_reset_vector = vec;
96
97 /* Map real mode platter into kas so kernel can access it. */
98 hat_devload(kas.a_hat,
99 (caddr_t)(uintptr_t)rm_platter_pa, MMU_PAGESIZE,
100 btop(rm_platter_pa), PROT_READ | PROT_WRITE | PROT_EXEC,
101 HAT_LOAD_NOCONSIST);
102
103 /* Copy CPU startup code to rm_platter if it's still during boot. */
104 if (!plat_dr_enabled()) {
105 ASSERT((size_t)real_mode_start_cpu_end -
106 (size_t)real_mode_start_cpu <= RM_PLATTER_CODE_SIZE);
107 bcopy((caddr_t)real_mode_start_cpu, (caddr_t)rm->rm_code,
108 (size_t)real_mode_start_cpu_end -
109 (size_t)real_mode_start_cpu);
110 }
111
112 return (0);
113 }
114
115 void
mach_cpucontext_fini(void)116 mach_cpucontext_fini(void)
117 {
118 if (warm_reset_vector)
119 psm_unmap_phys((caddr_t)warm_reset_vector,
120 sizeof (warm_reset_vector));
121 hat_unload(kas.a_hat, (caddr_t)(uintptr_t)rm_platter_pa, MMU_PAGESIZE,
122 HAT_UNLOAD);
123 }
124
125 #if defined(__amd64)
126 extern void *long_mode_64(void);
127 #endif /* __amd64 */
128
129 /*ARGSUSED*/
130 void
rmp_gdt_init(rm_platter_t * rm)131 rmp_gdt_init(rm_platter_t *rm)
132 {
133
134 #if defined(__amd64)
135 /* Use the kas address space for the CPU startup thread. */
136 if (MAKECR3(kas.a_hat->hat_htable->ht_pfn) > 0xffffffffUL)
137 panic("Cannot initialize CPUs; kernel's 64-bit page tables\n"
138 "located above 4G in physical memory (@ 0x%lx)",
139 MAKECR3(kas.a_hat->hat_htable->ht_pfn));
140
141 /*
142 * Setup pseudo-descriptors for temporary GDT and IDT for use ONLY
143 * by code in real_mode_start_cpu():
144 *
145 * GDT[0]: NULL selector
146 * GDT[1]: 64-bit CS: Long = 1, Present = 1, bits 12, 11 = 1
147 *
148 * Clear the IDT as interrupts will be off and a limit of 0 will cause
149 * the CPU to triple fault and reset on an NMI, seemingly as reasonable
150 * a course of action as any other, though it may cause the entire
151 * platform to reset in some cases...
152 */
153 rm->rm_temp_gdt[0] = 0;
154 rm->rm_temp_gdt[TEMPGDT_KCODE64] = 0x20980000000000ULL;
155
156 rm->rm_temp_gdt_lim = (ushort_t)(sizeof (rm->rm_temp_gdt) - 1);
157 rm->rm_temp_gdt_base = rm_platter_pa +
158 (uint32_t)offsetof(rm_platter_t, rm_temp_gdt);
159 rm->rm_temp_idt_lim = 0;
160 rm->rm_temp_idt_base = 0;
161
162 /*
163 * Since the CPU needs to jump to protected mode using an identity
164 * mapped address, we need to calculate it here.
165 */
166 rm->rm_longmode64_addr = rm_platter_pa +
167 (uint32_t)((uintptr_t)long_mode_64 -
168 (uintptr_t)real_mode_start_cpu);
169 #endif /* __amd64 */
170 }
171
172 static void *
mach_cpucontext_alloc_tables(struct cpu * cp)173 mach_cpucontext_alloc_tables(struct cpu *cp)
174 {
175 tss_t *ntss;
176 struct cpu_tables *ct;
177
178 /*
179 * Allocate space for stack, tss, gdt and idt. We round the size
180 * allotted for cpu_tables up, so that the TSS is on a unique page.
181 * This is more efficient when running in virtual machines.
182 */
183 ct = kmem_zalloc(P2ROUNDUP(sizeof (*ct), PAGESIZE), KM_SLEEP);
184 if ((uintptr_t)ct & PAGEOFFSET)
185 panic("mach_cpucontext_alloc_tables: cpu%d misaligned tables",
186 cp->cpu_id);
187
188 ntss = cp->cpu_tss = &ct->ct_tss;
189
190 #if defined(__amd64)
191
192 /*
193 * #DF (double fault).
194 */
195 ntss->tss_ist1 = (uint64_t)&ct->ct_stack[sizeof (ct->ct_stack)];
196
197 #elif defined(__i386)
198
199 ntss->tss_esp0 = ntss->tss_esp1 = ntss->tss_esp2 = ntss->tss_esp =
200 (uint32_t)&ct->ct_stack[sizeof (ct->ct_stack)];
201
202 ntss->tss_ss0 = ntss->tss_ss1 = ntss->tss_ss2 = ntss->tss_ss = KDS_SEL;
203
204 ntss->tss_eip = (uint32_t)cp->cpu_thread->t_pc;
205
206 ntss->tss_cs = KCS_SEL;
207 ntss->tss_ds = ntss->tss_es = KDS_SEL;
208 ntss->tss_fs = KFS_SEL;
209 ntss->tss_gs = KGS_SEL;
210
211 #endif /* __i386 */
212
213 /*
214 * Set I/O bit map offset equal to size of TSS segment limit
215 * for no I/O permission map. This will cause all user I/O
216 * instructions to generate #gp fault.
217 */
218 ntss->tss_bitmapbase = sizeof (*ntss);
219
220 /*
221 * Setup kernel tss.
222 */
223 set_syssegd((system_desc_t *)&cp->cpu_gdt[GDT_KTSS], cp->cpu_tss,
224 sizeof (*cp->cpu_tss) - 1, SDT_SYSTSS, SEL_KPL);
225
226 return (ct);
227 }
228
229 void *
mach_cpucontext_xalloc(struct cpu * cp,int optype)230 mach_cpucontext_xalloc(struct cpu *cp, int optype)
231 {
232 size_t len;
233 struct cpu_tables *ct;
234 rm_platter_t *rm = (rm_platter_t *)rm_platter_va;
235 static int cpu_halt_code_ready;
236
237 if (optype == MACH_CPUCONTEXT_OP_STOP) {
238 ASSERT(plat_dr_enabled());
239
240 /*
241 * The WARM_RESET_VECTOR has a limitation that the physical
242 * address written to it must be page-aligned. To work around
243 * this limitation, the CPU stop code has been splitted into
244 * two stages.
245 * The stage 2 code, which implements the real logic to halt
246 * CPUs, is copied to the rm_cpu_halt_code field in the real
247 * mode platter. The stage 1 code, which simply jumps to the
248 * stage 2 code in the rm_cpu_halt_code field, is copied to
249 * rm_code field in the real mode platter and it may be
250 * overwritten after the CPU has been stopped.
251 */
252 if (!cpu_halt_code_ready) {
253 /*
254 * The rm_cpu_halt_code field in the real mode platter
255 * is used by the CPU stop code only. So only copy the
256 * CPU stop stage 2 code into the rm_cpu_halt_code
257 * field on the first call.
258 */
259 len = (size_t)real_mode_stop_cpu_stage2_end -
260 (size_t)real_mode_stop_cpu_stage2;
261 ASSERT(len <= RM_PLATTER_CPU_HALT_CODE_SIZE);
262 bcopy((caddr_t)real_mode_stop_cpu_stage2,
263 (caddr_t)rm->rm_cpu_halt_code, len);
264 cpu_halt_code_ready = 1;
265 }
266
267 /*
268 * The rm_code field in the real mode platter is shared by
269 * the CPU start, CPU stop, CPR and fast reboot code. So copy
270 * the CPU stop stage 1 code into the rm_code field every time.
271 */
272 len = (size_t)real_mode_stop_cpu_stage1_end -
273 (size_t)real_mode_stop_cpu_stage1;
274 ASSERT(len <= RM_PLATTER_CODE_SIZE);
275 bcopy((caddr_t)real_mode_stop_cpu_stage1,
276 (caddr_t)rm->rm_code, len);
277 rm->rm_cpu_halted = 0;
278
279 return (cp->cpu_m.mcpu_mach_ctx_ptr);
280 } else if (optype != MACH_CPUCONTEXT_OP_START) {
281 return (NULL);
282 }
283
284 /*
285 * Only need to allocate tables when starting CPU.
286 * Tables allocated when starting CPU will be reused when stopping CPU.
287 */
288 ct = mach_cpucontext_alloc_tables(cp);
289 if (ct == NULL) {
290 return (NULL);
291 }
292
293 /* Copy CPU startup code to rm_platter for CPU hot-add operations. */
294 if (plat_dr_enabled()) {
295 bcopy((caddr_t)real_mode_start_cpu, (caddr_t)rm->rm_code,
296 (size_t)real_mode_start_cpu_end -
297 (size_t)real_mode_start_cpu);
298 }
299
300 /*
301 * Now copy all that we've set up onto the real mode platter
302 * for the real mode code to digest as part of starting the cpu.
303 */
304 rm->rm_idt_base = cp->cpu_idt;
305 rm->rm_idt_lim = sizeof (*cp->cpu_idt) * NIDT - 1;
306 rm->rm_gdt_base = cp->cpu_gdt;
307 rm->rm_gdt_lim = sizeof (*cp->cpu_gdt) * NGDT - 1;
308
309 /*
310 * CPU needs to access kernel address space after powering on.
311 * When hot-adding CPU at runtime, directly use top level page table
312 * of kas other than the return value of getcr3(). getcr3() returns
313 * current process's top level page table, which may be different from
314 * the one of kas.
315 */
316 rm->rm_pdbr = MAKECR3(kas.a_hat->hat_htable->ht_pfn);
317 rm->rm_cpu = cp->cpu_id;
318
319 /*
320 * For hot-adding CPU at runtime, Machine Check and Performance Counter
321 * should be disabled. They will be enabled on demand after CPU powers
322 * on successfully
323 */
324 rm->rm_cr4 = getcr4();
325 rm->rm_cr4 &= ~(CR4_MCE | CR4_PCE);
326
327 rmp_gdt_init(rm);
328
329 return (ct);
330 }
331
332 void
mach_cpucontext_xfree(struct cpu * cp,void * arg,int err,int optype)333 mach_cpucontext_xfree(struct cpu *cp, void *arg, int err, int optype)
334 {
335 struct cpu_tables *ct = arg;
336
337 ASSERT(&ct->ct_tss == cp->cpu_tss);
338 if (optype == MACH_CPUCONTEXT_OP_START) {
339 switch (err) {
340 case 0:
341 /*
342 * Save pointer for reuse when stopping CPU.
343 */
344 cp->cpu_m.mcpu_mach_ctx_ptr = arg;
345 break;
346 case ETIMEDOUT:
347 /*
348 * The processor was poked, but failed to start before
349 * we gave up waiting for it. In case it starts later,
350 * don't free anything.
351 */
352 cp->cpu_m.mcpu_mach_ctx_ptr = arg;
353 break;
354 default:
355 /*
356 * Some other, passive, error occurred.
357 */
358 kmem_free(ct, P2ROUNDUP(sizeof (*ct), PAGESIZE));
359 cp->cpu_tss = NULL;
360 break;
361 }
362 } else if (optype == MACH_CPUCONTEXT_OP_STOP) {
363 switch (err) {
364 case 0:
365 /*
366 * Free resources allocated when starting CPU.
367 */
368 kmem_free(ct, P2ROUNDUP(sizeof (*ct), PAGESIZE));
369 cp->cpu_tss = NULL;
370 cp->cpu_m.mcpu_mach_ctx_ptr = NULL;
371 break;
372 default:
373 /*
374 * Don't touch table pointer in case of failure.
375 */
376 break;
377 }
378 } else {
379 ASSERT(0);
380 }
381 }
382
383 void *
mach_cpucontext_alloc(struct cpu * cp)384 mach_cpucontext_alloc(struct cpu *cp)
385 {
386 return (mach_cpucontext_xalloc(cp, MACH_CPUCONTEXT_OP_START));
387 }
388
389 void
mach_cpucontext_free(struct cpu * cp,void * arg,int err)390 mach_cpucontext_free(struct cpu *cp, void *arg, int err)
391 {
392 mach_cpucontext_xfree(cp, arg, err, MACH_CPUCONTEXT_OP_START);
393 }
394
395 /*
396 * "Enter monitor." Called via cross-call from stop_other_cpus().
397 */
398 void
mach_cpu_halt(char * msg)399 mach_cpu_halt(char *msg)
400 {
401 if (msg)
402 prom_printf("%s\n", msg);
403
404 /*CONSTANTCONDITION*/
405 while (1)
406 ;
407 }
408
409 void
mach_cpu_idle(void)410 mach_cpu_idle(void)
411 {
412 i86_halt();
413 }
414
415 void
mach_cpu_pause(volatile char * safe)416 mach_cpu_pause(volatile char *safe)
417 {
418 /*
419 * This cpu is now safe.
420 */
421 *safe = PAUSE_WAIT;
422 membar_enter(); /* make sure stores are flushed */
423
424 /*
425 * Now we wait. When we are allowed to continue, safe
426 * will be set to PAUSE_IDLE.
427 */
428 while (*safe != PAUSE_IDLE)
429 SMT_PAUSE();
430 }
431
432 /*
433 * Power on the target CPU.
434 */
435 int
mp_cpu_poweron(struct cpu * cp)436 mp_cpu_poweron(struct cpu *cp)
437 {
438 int error;
439 cpuset_t tempset;
440 processorid_t cpuid;
441
442 ASSERT(cp != NULL);
443 cpuid = cp->cpu_id;
444 if (use_mp == 0 || plat_dr_support_cpu() == 0) {
445 return (ENOTSUP);
446 } else if (cpuid < 0 || cpuid >= max_ncpus) {
447 return (EINVAL);
448 }
449
450 /*
451 * The currrent x86 implementaiton of mp_cpu_configure() and
452 * mp_cpu_poweron() have a limitation that mp_cpu_poweron() could only
453 * be called once after calling mp_cpu_configure() for a specific CPU.
454 * It's because mp_cpu_poweron() will destroy data structure created
455 * by mp_cpu_configure(). So reject the request if the CPU has already
456 * been powered on once after calling mp_cpu_configure().
457 * This limitaiton only affects the p_online syscall and the DR driver
458 * won't be affected because the DR driver always invoke public CPU
459 * management interfaces in the predefined order:
460 * cpu_configure()->cpu_poweron()...->cpu_poweroff()->cpu_unconfigure()
461 */
462 if (cpuid_checkpass(cp, 4) || cp->cpu_thread == cp->cpu_idle_thread) {
463 return (ENOTSUP);
464 }
465
466 /*
467 * Check if there's at least a Mbyte of kmem available
468 * before attempting to start the cpu.
469 */
470 if (kmem_avail() < 1024 * 1024) {
471 /*
472 * Kick off a reap in case that helps us with
473 * later attempts ..
474 */
475 kmem_reap();
476 return (ENOMEM);
477 }
478
479 affinity_set(CPU->cpu_id);
480
481 /*
482 * Start the target CPU. No need to call mach_cpucontext_fini()
483 * if mach_cpucontext_init() fails.
484 */
485 if ((error = mach_cpucontext_init()) == 0) {
486 error = mp_start_cpu_common(cp, B_FALSE);
487 mach_cpucontext_fini();
488 }
489 if (error != 0) {
490 affinity_clear();
491 return (error);
492 }
493
494 /* Wait for the target cpu to reach READY state. */
495 tempset = cpu_ready_set;
496 while (!CPU_IN_SET(tempset, cpuid)) {
497 delay(1);
498 tempset = *((volatile cpuset_t *)&cpu_ready_set);
499 }
500
501 /* Mark the target CPU as available for mp operation. */
502 CPUSET_ATOMIC_ADD(mp_cpus, cpuid);
503
504 /* Free the space allocated to hold the microcode file */
505 ucode_cleanup();
506
507 affinity_clear();
508
509 return (0);
510 }
511
512 #define MP_CPU_DETACH_MAX_TRIES 5
513 #define MP_CPU_DETACH_DELAY 100
514
515 static int
mp_cpu_detach_driver(dev_info_t * dip)516 mp_cpu_detach_driver(dev_info_t *dip)
517 {
518 int i;
519 int rv = EBUSY;
520 dev_info_t *pdip;
521
522 pdip = ddi_get_parent(dip);
523 ASSERT(pdip != NULL);
524 /*
525 * Check if caller holds pdip busy - can cause deadlocks in
526 * e_ddi_branch_unconfigure(), which calls devfs_clean().
527 */
528 if (DEVI_BUSY_OWNED(pdip)) {
529 return (EDEADLOCK);
530 }
531
532 for (i = 0; i < MP_CPU_DETACH_MAX_TRIES; i++) {
533 if (e_ddi_branch_unconfigure(dip, NULL, 0) == 0) {
534 rv = 0;
535 break;
536 }
537 DELAY(MP_CPU_DETACH_DELAY);
538 }
539
540 return (rv);
541 }
542
543 /*
544 * Power off the target CPU.
545 * Note: cpu_lock will be released and then reacquired.
546 */
547 int
mp_cpu_poweroff(struct cpu * cp)548 mp_cpu_poweroff(struct cpu *cp)
549 {
550 int rv = 0;
551 void *ctx;
552 dev_info_t *dip = NULL;
553 rm_platter_t *rm = (rm_platter_t *)rm_platter_va;
554 extern void cpupm_start(cpu_t *);
555 extern void cpupm_stop(cpu_t *);
556
557 ASSERT(cp != NULL);
558 ASSERT((cp->cpu_flags & CPU_OFFLINE) != 0);
559 ASSERT((cp->cpu_flags & CPU_QUIESCED) != 0);
560
561 if (use_mp == 0 || plat_dr_support_cpu() == 0) {
562 return (ENOTSUP);
563 }
564 /*
565 * There is no support for powering off cpu0 yet.
566 * There are many pieces of code which have a hard dependency on cpu0.
567 */
568 if (cp->cpu_id == 0) {
569 return (ENOTSUP);
570 };
571
572 if (mach_cpu_get_device_node(cp, &dip) != PSM_SUCCESS) {
573 return (ENXIO);
574 }
575 ASSERT(dip != NULL);
576 if (mp_cpu_detach_driver(dip) != 0) {
577 rv = EBUSY;
578 goto out_online;
579 }
580
581 /* Allocate CPU context for stopping */
582 if (mach_cpucontext_init() != 0) {
583 rv = ENXIO;
584 goto out_online;
585 }
586 ctx = mach_cpucontext_xalloc(cp, MACH_CPUCONTEXT_OP_STOP);
587 if (ctx == NULL) {
588 rv = ENXIO;
589 goto out_context_fini;
590 }
591
592 cpupm_stop(cp);
593 cpu_event_fini_cpu(cp);
594
595 if (cp->cpu_m.mcpu_cmi_hdl != NULL) {
596 cmi_fini(cp->cpu_m.mcpu_cmi_hdl);
597 cp->cpu_m.mcpu_cmi_hdl = NULL;
598 }
599
600 rv = mach_cpu_stop(cp, ctx);
601 if (rv != 0) {
602 goto out_enable_cmi;
603 }
604
605 /* Wait until the target CPU has been halted. */
606 while (*(volatile ushort_t *)&(rm->rm_cpu_halted) != 0xdead) {
607 delay(1);
608 }
609 rm->rm_cpu_halted = 0xffff;
610
611 /* CPU_READY has been cleared by mach_cpu_stop. */
612 ASSERT((cp->cpu_flags & CPU_READY) == 0);
613 ASSERT((cp->cpu_flags & CPU_RUNNING) == 0);
614 cp->cpu_flags = CPU_OFFLINE | CPU_QUIESCED | CPU_POWEROFF;
615 CPUSET_ATOMIC_DEL(mp_cpus, cp->cpu_id);
616
617 mach_cpucontext_xfree(cp, ctx, 0, MACH_CPUCONTEXT_OP_STOP);
618 mach_cpucontext_fini();
619
620 return (0);
621
622 out_enable_cmi:
623 {
624 cmi_hdl_t hdl;
625
626 if ((hdl = cmi_init(CMI_HDL_NATIVE, cmi_ntv_hwchipid(cp),
627 cmi_ntv_hwcoreid(cp), cmi_ntv_hwstrandid(cp))) != NULL) {
628 if (is_x86_feature(x86_featureset, X86FSET_MCA))
629 cmi_mca_init(hdl);
630 cp->cpu_m.mcpu_cmi_hdl = hdl;
631 }
632 }
633 cpu_event_init_cpu(cp);
634 cpupm_start(cp);
635 mach_cpucontext_xfree(cp, ctx, rv, MACH_CPUCONTEXT_OP_STOP);
636
637 out_context_fini:
638 mach_cpucontext_fini();
639
640 out_online:
641 (void) e_ddi_branch_configure(dip, NULL, 0);
642
643 if (rv != EAGAIN && rv != ETIME) {
644 rv = ENXIO;
645 }
646
647 return (rv);
648 }
649
650 /*
651 * Return vcpu state, since this could be a virtual environment that we
652 * are unaware of, return "unknown".
653 */
654 /* ARGSUSED */
655 int
vcpu_on_pcpu(processorid_t cpu)656 vcpu_on_pcpu(processorid_t cpu)
657 {
658 return (VCPU_STATE_UNKNOWN);
659 }
660