sys/x86/xen/hvm.c

   1 /*
   2  * Copyright (c) 2008, 2013 Citrix Systems, Inc.
   3  * Copyright (c) 2012 Spectra Logic Corporation
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __FBSDID("$FreeBSD$");
  30
  31 #include <sys/param.h>
  32 #include <sys/bus.h>
  33 #include <sys/kernel.h>
  34 #include <sys/malloc.h>
  35 #include <sys/proc.h>
  36 #include <sys/smp.h>
  37 #include <sys/systm.h>
  38
  39 #include <vm/vm.h>
  40 #include <vm/pmap.h>
  41
  42 #include <dev/pci/pcivar.h>
  43
  44 #include <machine/cpufunc.h>
  45 #include <machine/cpu.h>
  46 #include <machine/smp.h>
  47
  48 #include <x86/apicreg.h>
  49
  50 #include <xen/xen-os.h>
  51 #include <xen/features.h>
  52 #include <xen/gnttab.h>
  53 #include <xen/hypervisor.h>
  54 #include <xen/hvm.h>
  55 #include <xen/xen_intr.h>
  56
  57 #include <xen/interface/hvm/params.h>
  58 #include <xen/interface/vcpu.h>
  59
  60 /*--------------------------- Forward Declarations ---------------------------*/
  61 #ifdef SMP
  62 static driver_filter_t xen_smp_rendezvous_action;
  63 static driver_filter_t xen_invltlb;
  64 static driver_filter_t xen_invlpg;
  65 static driver_filter_t xen_invlrng;
  66 static driver_filter_t xen_invlcache;
  67 #ifdef __i386__
  68 static driver_filter_t xen_lazypmap;
  69 #endif
  70 static driver_filter_t xen_ipi_bitmap_handler;
  71 static driver_filter_t xen_cpustop_handler;
  72 static driver_filter_t xen_cpususpend_handler;
  73 static driver_filter_t xen_cpustophard_handler;
  74 static void xen_ipi_vectored(u_int vector, int dest);
  75 static void xen_hvm_cpu_resume(void);
  76 #endif
  77 static void xen_hvm_cpu_init(void);
  78
  79 /*---------------------------- Extern Declarations ---------------------------*/
  80 #ifdef __i386__
  81 extern void pmap_lazyfix_action(void);
  82 #endif
  83 #ifdef __amd64__
  84 extern int pmap_pcid_enabled;
  85 #endif
  86
  87 /* Variables used by mp_machdep to perform the bitmap IPI */
  88 extern volatile u_int cpu_ipi_pending[MAXCPU];
  89
  90 /*---------------------------------- Macros ----------------------------------*/
  91 #define IPI_TO_IDX(ipi) ((ipi) - APIC_IPI_INTS)
  92
  93 /*-------------------------------- Local Types -------------------------------*/
  94 enum xen_hvm_init_type {
  95         XEN_HVM_INIT_COLD,
  96         XEN_HVM_INIT_CANCELLED_SUSPEND,
  97         XEN_HVM_INIT_RESUME
  98 };
  99
 100 struct xen_ipi_handler
 101 {
 102         driver_filter_t *filter;
 103         const char      *description;
 104 };
 105
 106 /*-------------------------------- Global Data -------------------------------*/
 107 enum xen_domain_type xen_domain_type = XEN_NATIVE;
 108
 109 #ifdef SMP
 110 struct cpu_ops xen_hvm_cpu_ops = {
 111         .ipi_vectored   = lapic_ipi_vectored,
 112         .cpu_init       = xen_hvm_cpu_init,
 113         .cpu_resume     = xen_hvm_cpu_resume
 114 };
 115 #endif
 116
 117 static MALLOC_DEFINE(M_XENHVM, "xen_hvm", "Xen HVM PV Support");
 118
 119 #ifdef SMP
 120 static struct xen_ipi_handler xen_ipis[] =
 121 {
 122         [IPI_TO_IDX(IPI_RENDEZVOUS)]    = { xen_smp_rendezvous_action,  "r"   },
 123         [IPI_TO_IDX(IPI_INVLTLB)]       = { xen_invltlb,                "itlb"},
 124         [IPI_TO_IDX(IPI_INVLPG)]        = { xen_invlpg,                 "ipg" },
 125         [IPI_TO_IDX(IPI_INVLRNG)]       = { xen_invlrng,                "irg" },
 126         [IPI_TO_IDX(IPI_INVLCACHE)]     = { xen_invlcache,              "ic"  },
 127 #ifdef __i386__
 128         [IPI_TO_IDX(IPI_LAZYPMAP)]      = { xen_lazypmap,               "lp"  },
 129 #endif
 130         [IPI_TO_IDX(IPI_BITMAP_VECTOR)] = { xen_ipi_bitmap_handler,     "b"   },
 131         [IPI_TO_IDX(IPI_STOP)]          = { xen_cpustop_handler,        "st"  },
 132         [IPI_TO_IDX(IPI_SUSPEND)]       = { xen_cpususpend_handler,     "sp"  },
 133         [IPI_TO_IDX(IPI_STOP_HARD)]     = { xen_cpustophard_handler,    "sth" },
 134 };
 135 #endif
 136
 137 /**
 138  * If non-zero, the hypervisor has been configured to use a direct
 139  * IDT event callback for interrupt injection.
 140  */
 141 int xen_vector_callback_enabled;
 142
 143 /*------------------------------- Per-CPU Data -------------------------------*/
 144 DPCPU_DEFINE(struct vcpu_info, vcpu_local_info);
 145 DPCPU_DEFINE(struct vcpu_info *, vcpu_info);
 146 #ifdef SMP
 147 DPCPU_DEFINE(xen_intr_handle_t, ipi_handle[nitems(xen_ipis)]);
 148 #endif
 149
 150 /*------------------ Hypervisor Access Shared Memory Regions -----------------*/
 151 /** Hypercall table accessed via HYPERVISOR_*_op() methods. */
 152 extern char *hypercall_page;
 153 shared_info_t *HYPERVISOR_shared_info;
 154 start_info_t *HYPERVISOR_start_info;
 155
 156 #ifdef SMP
 157 /*---------------------------- XEN PV IPI Handlers ---------------------------*/
 158 /*
 159  * This are C clones of the ASM functions found in apic_vector.s
 160  */
 161 static int
 162 xen_ipi_bitmap_handler(void *arg)
 163 {
 164         struct trapframe *frame;
 165
 166         frame = arg;
 167         ipi_bitmap_handler(*frame);
 168         return (FILTER_HANDLED);
 169 }
 170
 171 static int
 172 xen_smp_rendezvous_action(void *arg)
 173 {
 174 #ifdef COUNT_IPIS
 175         (*ipi_rendezvous_counts[PCPU_GET(cpuid)])++;
 176 #endif /* COUNT_IPIS */
 177
 178         smp_rendezvous_action();
 179         return (FILTER_HANDLED);
 180 }
 181
 182 static int
 183 xen_invltlb(void *arg)
 184 {
 185
 186         invltlb_handler();
 187         return (FILTER_HANDLED);
 188 }
 189
 190 #ifdef __amd64__
 191 static int
 192 xen_invltlb_pcid(void *arg)
 193 {
 194
 195         invltlb_pcid_handler();
 196         return (FILTER_HANDLED);
 197 }
 198 #endif
 199
 200 static int
 201 xen_invlpg(void *arg)
 202 {
 203
 204         invlpg_handler();
 205         return (FILTER_HANDLED);
 206 }
 207
 208 #ifdef __amd64__
 209 static int
 210 xen_invlpg_pcid(void *arg)
 211 {
 212
 213         invlpg_pcid_handler();
 214         return (FILTER_HANDLED);
 215 }
 216 #endif
 217
 218 static int
 219 xen_invlrng(void *arg)
 220 {
 221
 222         invlrng_handler();
 223         return (FILTER_HANDLED);
 224 }
 225
 226 static int
 227 xen_invlcache(void *arg)
 228 {
 229
 230         invlcache_handler();
 231         return (FILTER_HANDLED);
 232 }
 233
 234 #ifdef __i386__
 235 static int
 236 xen_lazypmap(void *arg)
 237 {
 238
 239         pmap_lazyfix_action();
 240         return (FILTER_HANDLED);
 241 }
 242 #endif
 243
 244 static int
 245 xen_cpustop_handler(void *arg)
 246 {
 247
 248         cpustop_handler();
 249         return (FILTER_HANDLED);
 250 }
 251
 252 static int
 253 xen_cpususpend_handler(void *arg)
 254 {
 255
 256         cpususpend_handler();
 257         return (FILTER_HANDLED);
 258 }
 259
 260 static int
 261 xen_cpustophard_handler(void *arg)
 262 {
 263
 264         ipi_nmi_handler();
 265         return (FILTER_HANDLED);
 266 }
 267
 268 /* Xen PV IPI sender */
 269 static void
 270 xen_ipi_vectored(u_int vector, int dest)
 271 {
 272         xen_intr_handle_t *ipi_handle;
 273         int ipi_idx, to_cpu, self;
 274
 275         ipi_idx = IPI_TO_IDX(vector);
 276         if (ipi_idx > nitems(xen_ipis))
 277                 panic("IPI out of range");
 278
 279         switch(dest) {
 280         case APIC_IPI_DEST_SELF:
 281                 ipi_handle = DPCPU_GET(ipi_handle);
 282                 xen_intr_signal(ipi_handle[ipi_idx]);
 283                 break;
 284         case APIC_IPI_DEST_ALL:
 285                 CPU_FOREACH(to_cpu) {
 286                         ipi_handle = DPCPU_ID_GET(to_cpu, ipi_handle);
 287                         xen_intr_signal(ipi_handle[ipi_idx]);
 288                 }
 289                 break;
 290         case APIC_IPI_DEST_OTHERS:
 291                 self = PCPU_GET(cpuid);
 292                 CPU_FOREACH(to_cpu) {
 293                         if (to_cpu != self) {
 294                                 ipi_handle = DPCPU_ID_GET(to_cpu, ipi_handle);
 295                                 xen_intr_signal(ipi_handle[ipi_idx]);
 296                         }
 297                 }
 298                 break;
 299         default:
 300                 to_cpu = apic_cpuid(dest);
 301                 ipi_handle = DPCPU_ID_GET(to_cpu, ipi_handle);
 302                 xen_intr_signal(ipi_handle[ipi_idx]);
 303                 break;
 304         }
 305 }
 306
 307 /* XEN diverged cpu operations */
 308 static void
 309 xen_hvm_cpu_resume(void)
 310 {
 311         u_int cpuid = PCPU_GET(cpuid);
 312
 313         /*
 314          * Reset pending bitmap IPIs, because Xen doesn't preserve pending
 315          * event channels on migration.
 316          */
 317         cpu_ipi_pending[cpuid] = 0;
 318
 319         /* register vcpu_info area */
 320         xen_hvm_cpu_init();
 321 }
 322
 323 static void
 324 xen_cpu_ipi_init(int cpu)
 325 {
 326         xen_intr_handle_t *ipi_handle;
 327         const struct xen_ipi_handler *ipi;
 328         device_t dev;
 329         int idx, rc;
 330
 331         ipi_handle = DPCPU_ID_GET(cpu, ipi_handle);
 332         dev = pcpu_find(cpu)->pc_device;
 333         KASSERT((dev != NULL), ("NULL pcpu device_t"));
 334
 335         for (ipi = xen_ipis, idx = 0; idx < nitems(xen_ipis); ipi++, idx++) {
 336
 337                 if (ipi->filter == NULL) {
 338                         ipi_handle[idx] = NULL;
 339                         continue;
 340                 }
 341
 342                 rc = xen_intr_alloc_and_bind_ipi(dev, cpu, ipi->filter,
 343                     INTR_TYPE_TTY, &ipi_handle[idx]);
 344                 if (rc != 0)
 345                         panic("Unable to allocate a XEN IPI port");
 346                 xen_intr_describe(ipi_handle[idx], "%s", ipi->description);
 347         }
 348 }
 349
 350 static void
 351 xen_setup_cpus(void)
 352 {
 353         int i;
 354
 355         if (!xen_vector_callback_enabled)
 356                 return;
 357
 358 #ifdef __amd64__
 359         if (pmap_pcid_enabled) {
 360                 xen_ipis[IPI_TO_IDX(IPI_INVLTLB)].filter = xen_invltlb_pcid;
 361                 xen_ipis[IPI_TO_IDX(IPI_INVLPG)].filter = xen_invlpg_pcid;
 362         }
 363 #endif
 364         CPU_FOREACH(i)
 365                 xen_cpu_ipi_init(i);
 366
 367         /* Set the xen pv ipi ops to replace the native ones */
 368         cpu_ops.ipi_vectored = xen_ipi_vectored;
 369 }
 370 #endif
 371
 372 /*---------------------- XEN Hypervisor Probe and Setup ----------------------*/
 373 static uint32_t
 374 xen_hvm_cpuid_base(void)
 375 {
 376         uint32_t base, regs[4];
 377
 378         for (base = 0x40000000; base < 0x40010000; base += 0x100) {
 379                 do_cpuid(base, regs);
 380                 if (!memcmp("XenVMMXenVMM", &regs[1], 12)
 381                     && (regs[0] - base) >= 2)
 382                         return (base);
 383         }
 384         return (0);
 385 }
 386
 387 /*
 388  * Allocate and fill in the hypcall page.
 389  */
 390 static int
 391 xen_hvm_init_hypercall_stubs(enum xen_hvm_init_type init_type)
 392 {
 393         uint32_t base, regs[4];
 394         int i;
 395
 396         if (xen_pv_domain()) {
 397                 /* hypercall page is already set in the PV case */
 398                 return (0);
 399         }
 400
 401         base = xen_hvm_cpuid_base();
 402         if (base == 0)
 403                 return (ENXIO);
 404
 405         if (init_type == XEN_HVM_INIT_COLD) {
 406                 do_cpuid(base + 1, regs);
 407                 printf("XEN: Hypervisor version %d.%d detected.\n",
 408                     regs[0] >> 16, regs[0] & 0xffff);
 409         }
 410
 411         /*
 412          * Find the hypercall pages.
 413          */
 414         do_cpuid(base + 2, regs);
 415
 416         for (i = 0; i < regs[0]; i++)
 417                 wrmsr(regs[1], vtophys(&hypercall_page + i * PAGE_SIZE) + i);
 418
 419         return (0);
 420 }
 421
 422 static void
 423 xen_hvm_init_shared_info_page(void)
 424 {
 425         struct xen_add_to_physmap xatp;
 426
 427         if (xen_pv_domain()) {
 428                 /*
 429                  * Already setup in the PV case, shared_info is passed inside
 430                  * of the start_info struct at start of day.
 431                  */
 432                 return;
 433         }
 434
 435         if (HYPERVISOR_shared_info == NULL) {
 436                 HYPERVISOR_shared_info = malloc(PAGE_SIZE, M_XENHVM, M_NOWAIT);
 437                 if (HYPERVISOR_shared_info == NULL)
 438                         panic("Unable to allocate Xen shared info page");
 439         }
 440
 441         xatp.domid = DOMID_SELF;
 442         xatp.idx = 0;
 443         xatp.space = XENMAPSPACE_shared_info;
 444         xatp.gpfn = vtophys(HYPERVISOR_shared_info) >> PAGE_SHIFT;
 445         if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
 446                 panic("HYPERVISOR_memory_op failed");
 447 }
 448
 449 /*
 450  * Tell the hypervisor how to contact us for event channel callbacks.
 451  */
 452 void
 453 xen_hvm_set_callback(device_t dev)
 454 {
 455         struct xen_hvm_param xhp;
 456         int irq;
 457
 458         if (xen_vector_callback_enabled)
 459                 return;
 460
 461         xhp.domid = DOMID_SELF;
 462         xhp.index = HVM_PARAM_CALLBACK_IRQ;
 463         if (xen_feature(XENFEAT_hvm_callback_vector) != 0) {
 464                 int error;
 465
 466                 xhp.value = HVM_CALLBACK_VECTOR(IDT_EVTCHN);
 467                 error = HYPERVISOR_hvm_op(HVMOP_set_param, &xhp);
 468                 if (error == 0) {
 469                         xen_vector_callback_enabled = 1;
 470                         return;
 471                 }
 472                 printf("Xen HVM callback vector registration failed (%d). "
 473                     "Falling back to emulated device interrupt\n", error);
 474         }
 475         xen_vector_callback_enabled = 0;
 476         if (dev == NULL) {
 477                 /*
 478                  * Called from early boot or resume.
 479                  * xenpci will invoke us again later.
 480                  */
 481                 return;
 482         }
 483
 484         irq = pci_get_irq(dev);
 485         if (irq < 16) {
 486                 xhp.value = HVM_CALLBACK_GSI(irq);
 487         } else {
 488                 u_int slot;
 489                 u_int pin;
 490
 491                 slot = pci_get_slot(dev);
 492                 pin = pci_get_intpin(dev) - 1;
 493                 xhp.value = HVM_CALLBACK_PCI_INTX(slot, pin);
 494         }
 495
 496         if (HYPERVISOR_hvm_op(HVMOP_set_param, &xhp) != 0)
 497                 panic("Can't set evtchn callback");
 498 }
 499
 500 #define XEN_MAGIC_IOPORT 0x10
 501 enum {
 502         XMI_MAGIC                        = 0x49d2,
 503         XMI_UNPLUG_IDE_DISKS             = 0x01,
 504         XMI_UNPLUG_NICS                  = 0x02,
 505         XMI_UNPLUG_IDE_EXCEPT_PRI_MASTER = 0x04
 506 };
 507
 508 static void
 509 xen_hvm_disable_emulated_devices(void)
 510 {
 511
 512         if (xen_pv_domain()) {
 513                 /*
 514                  * No emulated devices in the PV case, so no need to unplug
 515                  * anything.
 516                  */
 517                 return;
 518         }
 519
 520         if (inw(XEN_MAGIC_IOPORT) != XMI_MAGIC)
 521                 return;
 522
 523         if (bootverbose)
 524                 printf("XEN: Disabling emulated block and network devices\n");
 525         outw(XEN_MAGIC_IOPORT, XMI_UNPLUG_IDE_DISKS|XMI_UNPLUG_NICS);
 526 }
 527
 528 static void
 529 xen_hvm_init(enum xen_hvm_init_type init_type)
 530 {
 531         int error;
 532         int i;
 533
 534         if (init_type == XEN_HVM_INIT_CANCELLED_SUSPEND)
 535                 return;
 536
 537         error = xen_hvm_init_hypercall_stubs(init_type);
 538
 539         switch (init_type) {
 540         case XEN_HVM_INIT_COLD:
 541                 if (error != 0)
 542                         return;
 543
 544                 /*
 545                  * If xen_domain_type is not set at this point
 546                  * it means we are inside a (PV)HVM guest, because
 547                  * for PVH the guest type is set much earlier
 548                  * (see hammer_time_xen).
 549                  */
 550                 if (!xen_domain()) {
 551                         xen_domain_type = XEN_HVM_DOMAIN;
 552                         vm_guest = VM_GUEST_XEN;
 553                 }
 554
 555                 setup_xen_features();
 556 #ifdef SMP
 557                 cpu_ops = xen_hvm_cpu_ops;
 558 #endif
 559                 break;
 560         case XEN_HVM_INIT_RESUME:
 561                 if (error != 0)
 562                         panic("Unable to init Xen hypercall stubs on resume");
 563
 564                 /* Clear stale vcpu_info. */
 565                 CPU_FOREACH(i)
 566                         DPCPU_ID_SET(i, vcpu_info, NULL);
 567                 break;
 568         default:
 569                 panic("Unsupported HVM initialization type");
 570         }
 571
 572         xen_vector_callback_enabled = 0;
 573         xen_hvm_set_callback(NULL);
 574
 575         /*
 576          * On (PV)HVM domains we need to request the hypervisor to
 577          * fill the shared info page, for PVH guest the shared_info page
 578          * is passed inside the start_info struct and is already set, so this
 579          * functions are no-ops.
 580          */
 581         xen_hvm_init_shared_info_page();
 582         xen_hvm_disable_emulated_devices();
 583 }
 584
 585 void
 586 xen_hvm_suspend(void)
 587 {
 588 }
 589
 590 void
 591 xen_hvm_resume(bool suspend_cancelled)
 592 {
 593
 594         xen_hvm_init(suspend_cancelled ?
 595             XEN_HVM_INIT_CANCELLED_SUSPEND : XEN_HVM_INIT_RESUME);
 596
 597         /* Register vcpu_info area for CPU#0. */
 598         xen_hvm_cpu_init();
 599 }
 600
 601 static void
 602 xen_hvm_sysinit(void *arg __unused)
 603 {
 604         xen_hvm_init(XEN_HVM_INIT_COLD);
 605 }
 606
 607 static void
 608 xen_set_vcpu_id(void)
 609 {
 610         struct pcpu *pc;
 611         int i;
 612
 613         if (!xen_hvm_domain())
 614                 return;
 615
 616         /* Set vcpu_id to acpi_id */
 617         CPU_FOREACH(i) {
 618                 pc = pcpu_find(i);
 619                 pc->pc_vcpu_id = pc->pc_acpi_id;
 620                 if (bootverbose)
 621                         printf("XEN: CPU %u has VCPU ID %u\n",
 622                                i, pc->pc_vcpu_id);
 623         }
 624 }
 625
 626 static void
 627 xen_hvm_cpu_init(void)
 628 {
 629         struct vcpu_register_vcpu_info info;
 630         struct vcpu_info *vcpu_info;
 631         int cpu, rc;
 632
 633         if (!xen_domain())
 634                 return;
 635
 636         if (DPCPU_GET(vcpu_info) != NULL) {
 637                 /*
 638                  * vcpu_info is already set.  We're resuming
 639                  * from a failed migration and our pre-suspend
 640                  * configuration is still valid.
 641                  */
 642                 return;
 643         }
 644
 645         vcpu_info = DPCPU_PTR(vcpu_local_info);
 646         cpu = PCPU_GET(vcpu_id);
 647         info.mfn = vtophys(vcpu_info) >> PAGE_SHIFT;
 648         info.offset = vtophys(vcpu_info) - trunc_page(vtophys(vcpu_info));
 649
 650         rc = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
 651         if (rc != 0)
 652                 DPCPU_SET(vcpu_info, &HYPERVISOR_shared_info->vcpu_info[cpu]);
 653         else
 654                 DPCPU_SET(vcpu_info, vcpu_info);
 655 }
 656
 657 SYSINIT(xen_hvm_init, SI_SUB_HYPERVISOR, SI_ORDER_FIRST, xen_hvm_sysinit, NULL);
 658 #ifdef SMP
 659 /* We need to setup IPIs before APs are started */
 660 SYSINIT(xen_setup_cpus, SI_SUB_SMP-1, SI_ORDER_FIRST, xen_setup_cpus, NULL);
 661 #endif
 662 SYSINIT(xen_hvm_cpu_init, SI_SUB_INTR, SI_ORDER_FIRST, xen_hvm_cpu_init, NULL);
 663 SYSINIT(xen_set_vcpu_id, SI_SUB_CPU, SI_ORDER_ANY, xen_set_vcpu_id, NULL);