src/basic/virt.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2011 Lennart Poettering
   6
   7   systemd is free software; you can redistribute it and/or modify it
   8   under the terms of the GNU Lesser General Public License as published by
   9   the Free Software Foundation; either version 2.1 of the License, or
  10   (at your option) any later version.
  11
  12   systemd is distributed in the hope that it will be useful, but
  13   WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15   Lesser General Public License for more details.
  16
  17   You should have received a copy of the GNU Lesser General Public License
  18   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  19 ***/
  20
  21 #if defined(__i386__) || defined(__x86_64__)
  22 #include <cpuid.h>
  23 #endif
  24 #include <errno.h>
  25 #include <stdint.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <unistd.h>
  29
  30 #include "alloc-util.h"
  31 #include "dirent-util.h"
  32 #include "env-util.h"
  33 #include "fd-util.h"
  34 #include "fileio.h"
  35 #include "macro.h"
  36 #include "process-util.h"
  37 #include "stat-util.h"
  38 #include "string-table.h"
  39 #include "string-util.h"
  40 #include "virt.h"
  41
  42 static int detect_vm_cpuid(void) {
  43
  44         /* CPUID is an x86 specific interface. */
  45 #if defined(__i386__) || defined(__x86_64__)
  46
  47         static const struct {
  48                 const char *cpuid;
  49                 int id;
  50         } cpuid_vendor_table[] = {
  51                 { "XenVMMXenVMM", VIRTUALIZATION_XEN       },
  52                 { "KVMKVMKVM",    VIRTUALIZATION_KVM       },
  53                 { "TCGTCGTCGTCG", VIRTUALIZATION_QEMU      },
  54                 /* http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 */
  55                 { "VMwareVMware", VIRTUALIZATION_VMWARE    },
  56                 /* https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs */
  57                 { "Microsoft Hv", VIRTUALIZATION_MICROSOFT },
  58                 /* https://wiki.freebsd.org/bhyve */
  59                 { "bhyve bhyve ", VIRTUALIZATION_BHYVE     },
  60         };
  61
  62         uint32_t eax, ebx, ecx, edx;
  63         bool hypervisor;
  64
  65         /* http://lwn.net/Articles/301888/ */
  66
  67         /* First detect whether there is a hypervisor */
  68         if (__get_cpuid(1, &eax, &ebx, &ecx, &edx) == 0)
  69                 return VIRTUALIZATION_NONE;
  70
  71         hypervisor = !!(ecx & 0x80000000U);
  72
  73         if (hypervisor) {
  74                 union {
  75                         uint32_t sig32[3];
  76                         char text[13];
  77                 } sig = {};
  78                 unsigned j;
  79
  80                 /* There is a hypervisor, see what it is */
  81                 __cpuid(0x40000000U, eax, ebx, ecx, edx);
  82
  83                 sig.sig32[0] = ebx;
  84                 sig.sig32[1] = ecx;
  85                 sig.sig32[2] = edx;
  86
  87                 log_debug("Virtualization found, CPUID=%s", sig.text);
  88
  89                 for (j = 0; j < ELEMENTSOF(cpuid_vendor_table); j ++)
  90                         if (streq(sig.text, cpuid_vendor_table[j].cpuid))
  91                                 return cpuid_vendor_table[j].id;
  92
  93                 return VIRTUALIZATION_VM_OTHER;
  94         }
  95 #endif
  96         log_debug("No virtualization found in CPUID");
  97
  98         return VIRTUALIZATION_NONE;
  99 }
 100
 101 static int detect_vm_device_tree(void) {
 102 #if defined(__arm__) || defined(__aarch64__) || defined(__powerpc__) || defined(__powerpc64__)
 103         _cleanup_free_ char *hvtype = NULL;
 104         int r;
 105
 106         r = read_one_line_file("/proc/device-tree/hypervisor/compatible", &hvtype);
 107         if (r == -ENOENT) {
 108                 _cleanup_closedir_ DIR *dir = NULL;
 109                 struct dirent *dent;
 110
 111                 dir = opendir("/proc/device-tree");
 112                 if (!dir) {
 113                         if (errno == ENOENT) {
 114                                 log_debug_errno(errno, "/proc/device-tree: %m");
 115                                 return VIRTUALIZATION_NONE;
 116                         }
 117                         return -errno;
 118                 }
 119
 120                 FOREACH_DIRENT(dent, dir, return -errno)
 121                         if (strstr(dent->d_name, "fw-cfg")) {
 122                                 log_debug("Virtualization QEMU: \"fw-cfg\" present in /proc/device-tree/%s", dent->d_name);
 123                                 return VIRTUALIZATION_QEMU;
 124                         }
 125
 126                 log_debug("No virtualization found in /proc/device-tree/*");
 127                 return VIRTUALIZATION_NONE;
 128         } else if (r < 0)
 129                 return r;
 130
 131         log_debug("Virtualization %s found in /proc/device-tree/hypervisor/compatible", hvtype);
 132         if (streq(hvtype, "linux,kvm"))
 133                 return VIRTUALIZATION_KVM;
 134         else if (strstr(hvtype, "xen"))
 135                 return VIRTUALIZATION_XEN;
 136         else
 137                 return VIRTUALIZATION_VM_OTHER;
 138 #else
 139         log_debug("This platform does not support /proc/device-tree");
 140         return VIRTUALIZATION_NONE;
 141 #endif
 142 }
 143
 144 static int detect_vm_dmi(void) {
 145 #if defined(__i386__) || defined(__x86_64__) || defined(__arm__) || defined(__aarch64__)
 146
 147         static const char *const dmi_vendors[] = {
 148                 "/sys/class/dmi/id/product_name", /* Test this before sys_vendor to detect KVM over QEMU */
 149                 "/sys/class/dmi/id/sys_vendor",
 150                 "/sys/class/dmi/id/board_vendor",
 151                 "/sys/class/dmi/id/bios_vendor"
 152         };
 153
 154         static const struct {
 155                 const char *vendor;
 156                 int id;
 157         } dmi_vendor_table[] = {
 158                 { "KVM",           VIRTUALIZATION_KVM       },
 159                 { "QEMU",          VIRTUALIZATION_QEMU      },
 160                 /* http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458 */
 161                 { "VMware",        VIRTUALIZATION_VMWARE    },
 162                 { "VMW",           VIRTUALIZATION_VMWARE    },
 163                 { "innotek GmbH",  VIRTUALIZATION_ORACLE    },
 164                 { "Xen",           VIRTUALIZATION_XEN       },
 165                 { "Bochs",         VIRTUALIZATION_BOCHS     },
 166                 { "Parallels",     VIRTUALIZATION_PARALLELS },
 167                 /* https://wiki.freebsd.org/bhyve */
 168                 { "BHYVE",         VIRTUALIZATION_BHYVE     },
 169         };
 170         unsigned i;
 171         int r;
 172
 173         for (i = 0; i < ELEMENTSOF(dmi_vendors); i++) {
 174                 _cleanup_free_ char *s = NULL;
 175                 unsigned j;
 176
 177                 r = read_one_line_file(dmi_vendors[i], &s);
 178                 if (r < 0) {
 179                         if (r == -ENOENT)
 180                                 continue;
 181
 182                         return r;
 183                 }
 184
 185                 for (j = 0; j < ELEMENTSOF(dmi_vendor_table); j++)
 186                         if (startswith(s, dmi_vendor_table[j].vendor)) {
 187                                 log_debug("Virtualization %s found in DMI (%s)", s, dmi_vendors[i]);
 188                                 return dmi_vendor_table[j].id;
 189                         }
 190         }
 191 #endif
 192
 193         log_debug("No virtualization found in DMI");
 194
 195         return VIRTUALIZATION_NONE;
 196 }
 197
 198 static int detect_vm_xen(void) {
 199
 200         /* Check for Dom0 will be executed later in detect_vm_xen_dom0
 201            The presence of /proc/xen indicates some form of a Xen domain */
 202         if (access("/proc/xen", F_OK) < 0) {
 203                 log_debug("Virtualization XEN not found, /proc/xen does not exist");
 204                 return VIRTUALIZATION_NONE;
 205         }
 206
 207         log_debug("Virtualization XEN found (/proc/xen exists)");
 208         return VIRTUALIZATION_XEN;
 209 }
 210
 211 #define XENFEAT_dom0 11 /* xen/include/public/features.h */
 212 #define PATH_FEATURES "/sys/hypervisor/properties/features"
 213 /* Returns -errno, or 0 for domU, or 1 for dom0 */
 214 static int detect_vm_xen_dom0(void) {
 215         _cleanup_free_ char *domcap = NULL;
 216         char *cap, *i;
 217         int r;
 218
 219         r = read_one_line_file(PATH_FEATURES, &domcap);
 220         if (r < 0 && r != -ENOENT)
 221                 return r;
 222         if (r == 0) {
 223                 unsigned long features;
 224
 225                 /* Here, we need to use sscanf() instead of safe_atoul()
 226                  * as the string lacks the leading "0x". */
 227                 r = sscanf(domcap, "%lx", &features);
 228                 if (r == 1) {
 229                         r = !!(features & (1U << XENFEAT_dom0));
 230                         log_debug("Virtualization XEN, found %s with value %08lx, "
 231                                   "XENFEAT_dom0 (indicating the 'hardware domain') is%s set.",
 232                                   PATH_FEATURES, features, r ? "" : " not");
 233                         return r;
 234                 }
 235                 log_debug("Virtualization XEN, found %s, unhandled content '%s'",
 236                           PATH_FEATURES, domcap);
 237         }
 238
 239         r = read_one_line_file("/proc/xen/capabilities", &domcap);
 240         if (r == -ENOENT) {
 241                 log_debug("Virtualization XEN because /proc/xen/capabilities does not exist");
 242                 return 0;
 243         }
 244         if (r < 0)
 245                 return r;
 246
 247         i = domcap;
 248         while ((cap = strsep(&i, ",")))
 249                 if (streq(cap, "control_d"))
 250                         break;
 251         if (!cap) {
 252                 log_debug("Virtualization XEN DomU found (/proc/xen/capabilites)");
 253                 return 0;
 254         }
 255
 256         log_debug("Virtualization XEN Dom0 ignored (/proc/xen/capabilities)");
 257         return 1;
 258 }
 259
 260 static int detect_vm_hypervisor(void) {
 261         _cleanup_free_ char *hvtype = NULL;
 262         int r;
 263
 264         r = read_one_line_file("/sys/hypervisor/type", &hvtype);
 265         if (r == -ENOENT)
 266                 return VIRTUALIZATION_NONE;
 267         if (r < 0)
 268                 return r;
 269
 270         log_debug("Virtualization %s found in /sys/hypervisor/type", hvtype);
 271
 272         if (streq(hvtype, "xen"))
 273                 return VIRTUALIZATION_XEN;
 274         else
 275                 return VIRTUALIZATION_VM_OTHER;
 276 }
 277
 278 static int detect_vm_uml(void) {
 279         _cleanup_free_ char *cpuinfo_contents = NULL;
 280         int r;
 281
 282         /* Detect User-Mode Linux by reading /proc/cpuinfo */
 283         r = read_full_file("/proc/cpuinfo", &cpuinfo_contents, NULL);
 284         if (r < 0)
 285                 return r;
 286
 287         if (strstr(cpuinfo_contents, "\nvendor_id\t: User Mode Linux\n")) {
 288                 log_debug("UML virtualization found in /proc/cpuinfo");
 289                 return VIRTUALIZATION_UML;
 290         }
 291
 292         log_debug("No virtualization found in /proc/cpuinfo.");
 293         return VIRTUALIZATION_NONE;
 294 }
 295
 296 static int detect_vm_zvm(void) {
 297
 298 #if defined(__s390__)
 299         _cleanup_free_ char *t = NULL;
 300         int r;
 301
 302         r = get_proc_field("/proc/sysinfo", "VM00 Control Program", WHITESPACE, &t);
 303         if (r == -ENOENT)
 304                 return VIRTUALIZATION_NONE;
 305         if (r < 0)
 306                 return r;
 307
 308         log_debug("Virtualization %s found in /proc/sysinfo", t);
 309         if (streq(t, "z/VM"))
 310                 return VIRTUALIZATION_ZVM;
 311         else
 312                 return VIRTUALIZATION_KVM;
 313 #else
 314         log_debug("This platform does not support /proc/sysinfo");
 315         return VIRTUALIZATION_NONE;
 316 #endif
 317 }
 318
 319 /* Returns a short identifier for the various VM implementations */
 320 int detect_vm(void) {
 321         static thread_local int cached_found = _VIRTUALIZATION_INVALID;
 322         int r, dmi;
 323         bool other = false;
 324
 325         if (cached_found >= 0)
 326                 return cached_found;
 327
 328         /* We have to use the correct order here:
 329          *
 330          * -> First try to detect Oracle Virtualbox, even if it uses KVM.
 331          * -> Second try to detect from cpuid, this will report KVM for
 332          *    whatever software is used even if info in dmi is overwritten.
 333          * -> Third try to detect from dmi. */
 334
 335         dmi = detect_vm_dmi();
 336         if (dmi == VIRTUALIZATION_ORACLE) {
 337                 r = dmi;
 338                 goto finish;
 339         }
 340
 341         r = detect_vm_cpuid();
 342         if (r < 0)
 343                 return r;
 344         if (r != VIRTUALIZATION_NONE) {
 345                 if (r == VIRTUALIZATION_VM_OTHER)
 346                         other = true;
 347                 else
 348                         goto finish;
 349         }
 350
 351         r = dmi;
 352         if (r < 0)
 353                 return r;
 354         if (r != VIRTUALIZATION_NONE) {
 355                 if (r == VIRTUALIZATION_VM_OTHER)
 356                         other = true;
 357                 else
 358                         goto finish;
 359         }
 360
 361         /* x86 xen will most likely be detected by cpuid. If not (most likely
 362          * because we're not an x86 guest), then we should try the /proc/xen
 363          * directory next. If that's not found, then we check for the high-level
 364          * hypervisor sysfs file.
 365          */
 366
 367         r = detect_vm_xen();
 368         if (r < 0)
 369                 return r;
 370         if (r != VIRTUALIZATION_NONE) {
 371                 if (r == VIRTUALIZATION_VM_OTHER)
 372                         other = true;
 373                 else
 374                         goto finish;
 375         }
 376
 377         r = detect_vm_hypervisor();
 378         if (r < 0)
 379                 return r;
 380         if (r != VIRTUALIZATION_NONE) {
 381                 if (r == VIRTUALIZATION_VM_OTHER)
 382                         other = true;
 383                 else
 384                         goto finish;
 385         }
 386
 387         r = detect_vm_device_tree();
 388         if (r < 0)
 389                 return r;
 390         if (r != VIRTUALIZATION_NONE) {
 391                 if (r == VIRTUALIZATION_VM_OTHER)
 392                         other = true;
 393                 else
 394                         goto finish;
 395         }
 396
 397         r = detect_vm_uml();
 398         if (r < 0)
 399                 return r;
 400         if (r != VIRTUALIZATION_NONE) {
 401                 if (r == VIRTUALIZATION_VM_OTHER)
 402                         other = true;
 403                 else
 404                         goto finish;
 405         }
 406
 407         r = detect_vm_zvm();
 408         if (r < 0)
 409                 return r;
 410
 411 finish:
 412         /* x86 xen Dom0 is detected as XEN in hypervisor and maybe others.
 413          * In order to detect the Dom0 as not virtualization we need to
 414          * double-check it */
 415         if (r == VIRTUALIZATION_XEN) {
 416                 int ret = detect_vm_xen_dom0();
 417                 if (ret < 0)
 418                         return ret;
 419                 if (ret > 0)
 420                         r = VIRTUALIZATION_NONE;
 421         } else if (r == VIRTUALIZATION_NONE && other)
 422                 r = VIRTUALIZATION_VM_OTHER;
 423
 424         cached_found = r;
 425         log_debug("Found VM virtualization %s", virtualization_to_string(r));
 426         return r;
 427 }
 428
 429 int detect_container(void) {
 430
 431         static const struct {
 432                 const char *value;
 433                 int id;
 434         } value_table[] = {
 435                 { "lxc",            VIRTUALIZATION_LXC            },
 436                 { "lxc-libvirt",    VIRTUALIZATION_LXC_LIBVIRT    },
 437                 { "systemd-nspawn", VIRTUALIZATION_SYSTEMD_NSPAWN },
 438                 { "docker",         VIRTUALIZATION_DOCKER         },
 439                 { "rkt",            VIRTUALIZATION_RKT            },
 440         };
 441
 442         static thread_local int cached_found = _VIRTUALIZATION_INVALID;
 443         _cleanup_free_ char *m = NULL;
 444         const char *e = NULL;
 445         unsigned j;
 446         int r;
 447
 448         if (cached_found >= 0)
 449                 return cached_found;
 450
 451         /* /proc/vz exists in container and outside of the container, /proc/bc only outside of the container. */
 452         if (access("/proc/vz", F_OK) >= 0 &&
 453             access("/proc/bc", F_OK) < 0) {
 454                 r = VIRTUALIZATION_OPENVZ;
 455                 goto finish;
 456         }
 457
 458         if (getpid_cached() == 1) {
 459                 /* If we are PID 1 we can just check our own environment variable, and that's authoritative. */
 460
 461                 e = getenv("container");
 462                 if (isempty(e)) {
 463                         r = VIRTUALIZATION_NONE;
 464                         goto finish;
 465                 }
 466
 467                 goto translate_name;
 468         }
 469
 470         /* Otherwise, PID 1 might have dropped this information into a file in /run. This is better than accessing
 471          * /proc/1/environ, since we don't need CAP_SYS_PTRACE for that. */
 472         r = read_one_line_file("/run/systemd/container", &m);
 473         if (r >= 0) {
 474                 e = m;
 475                 goto translate_name;
 476         }
 477         if (r != -ENOENT)
 478                 return log_debug_errno(r, "Failed to read /run/systemd/container: %m");
 479
 480         /* Fallback for cases where PID 1 was not systemd (for example, cases where init=/bin/sh is used. */
 481         r = getenv_for_pid(1, "container", &m);
 482         if (r > 0) {
 483                 e = m;
 484                 goto translate_name;
 485         }
 486         if (r < 0) /* This only works if we have CAP_SYS_PTRACE, hence let's better ignore failures here */
 487                 log_debug_errno(r, "Failed to read $container of PID 1, ignoring: %m");
 488
 489         /* Interestingly /proc/1/sched actually shows the host's PID for what we see as PID 1. Hence, if the PID shown
 490          * there is not 1, we know we are in a PID namespace. and hence a container. */
 491         r = read_one_line_file("/proc/1/sched", &m);
 492         if (r >= 0) {
 493                 const char *t;
 494
 495                 t = strrchr(m, '(');
 496                 if (!t)
 497                         return -EIO;
 498
 499                 if (!startswith(t, "(1,")) {
 500                         r = VIRTUALIZATION_CONTAINER_OTHER;
 501                         goto finish;
 502                 }
 503         } else if (r != -ENOENT)
 504                 return r;
 505
 506         /* If that didn't work, give up, assume no container manager. */
 507         r = VIRTUALIZATION_NONE;
 508         goto finish;
 509
 510 translate_name:
 511         for (j = 0; j < ELEMENTSOF(value_table); j++)
 512                 if (streq(e, value_table[j].value)) {
 513                         r = value_table[j].id;
 514                         goto finish;
 515                 }
 516
 517         r = VIRTUALIZATION_CONTAINER_OTHER;
 518
 519 finish:
 520         log_debug("Found container virtualization %s.", virtualization_to_string(r));
 521         cached_found = r;
 522         return r;
 523 }
 524
 525 int detect_virtualization(void) {
 526         int r;
 527
 528         r = detect_container();
 529         if (r == 0)
 530                 r = detect_vm();
 531
 532         return r;
 533 }
 534
 535 static int userns_has_mapping(const char *name) {
 536         _cleanup_fclose_ FILE *f = NULL;
 537         _cleanup_free_ char *buf = NULL;
 538         size_t n_allocated = 0;
 539         ssize_t n;
 540         uint32_t a, b, c;
 541         int r;
 542
 543         f = fopen(name, "re");
 544         if (!f) {
 545                 log_debug_errno(errno, "Failed to open %s: %m", name);
 546                 return errno == ENOENT ? false : -errno;
 547         }
 548
 549         n = getline(&buf, &n_allocated, f);
 550         if (n < 0) {
 551                 if (feof(f)) {
 552                         log_debug("%s is empty, we're in an uninitialized user namespace", name);
 553                         return true;
 554                 }
 555
 556                 return log_debug_errno(errno, "Failed to read %s: %m", name);
 557         }
 558
 559         r = sscanf(buf, "%"PRIu32" %"PRIu32" %"PRIu32, &a, &b, &c);
 560         if (r < 3)
 561                 return log_debug_errno(errno, "Failed to parse %s: %m", name);
 562
 563         if (a == 0 && b == 0 && c == UINT32_MAX) {
 564                 /* The kernel calls mappings_overlap() and does not allow overlaps */
 565                 log_debug("%s has a full 1:1 mapping", name);
 566                 return false;
 567         }
 568
 569         /* Anything else implies that we are in a user namespace */
 570         log_debug("Mapping found in %s, we're in a user namespace", name);
 571         return true;
 572 }
 573
 574 int running_in_userns(void) {
 575         _cleanup_free_ char *line = NULL;
 576         int r;
 577
 578         r = userns_has_mapping("/proc/self/uid_map");
 579         if (r != 0)
 580                 return r;
 581
 582         r = userns_has_mapping("/proc/self/gid_map");
 583         if (r != 0)
 584                 return r;
 585
 586         /* "setgroups" file was added in kernel v3.18-rc6-15-g9cc46516dd. It is also
 587          * possible to compile a kernel without CONFIG_USER_NS, in which case "setgroups"
 588          * also does not exist. We cannot distinguish those two cases, so assume that
 589          * we're running on a stripped-down recent kernel, rather than on an old one,
 590          * and if the file is not found, return false.
 591          */
 592         r = read_one_line_file("/proc/self/setgroups", &line);
 593         if (r < 0) {
 594                 log_debug_errno(r, "/proc/self/setgroups: %m");
 595                 return r == -ENOENT ? false : r;
 596         }
 597
 598         truncate_nl(line);
 599         r = streq(line, "deny");
 600         /* See user_namespaces(7) for a description of this "setgroups" contents. */
 601         log_debug("/proc/self/setgroups contains \"%s\", %s user namespace", line, r ? "in" : "not in");
 602         return r;
 603 }
 604
 605 int running_in_chroot(void) {
 606         int ret;
 607
 608         if (getenv_bool("SYSTEMD_IGNORE_CHROOT") > 0)
 609                 return 0;
 610
 611         ret = files_same("/proc/1/root", "/", 0);
 612         if (ret < 0)
 613                 return ret;
 614
 615         return ret == 0;
 616 }
 617
 618 static const char *const virtualization_table[_VIRTUALIZATION_MAX] = {
 619         [VIRTUALIZATION_NONE] = "none",
 620         [VIRTUALIZATION_KVM] = "kvm",
 621         [VIRTUALIZATION_QEMU] = "qemu",
 622         [VIRTUALIZATION_BOCHS] = "bochs",
 623         [VIRTUALIZATION_XEN] = "xen",
 624         [VIRTUALIZATION_UML] = "uml",
 625         [VIRTUALIZATION_VMWARE] = "vmware",
 626         [VIRTUALIZATION_ORACLE] = "oracle",
 627         [VIRTUALIZATION_MICROSOFT] = "microsoft",
 628         [VIRTUALIZATION_ZVM] = "zvm",
 629         [VIRTUALIZATION_PARALLELS] = "parallels",
 630         [VIRTUALIZATION_BHYVE] = "bhyve",
 631         [VIRTUALIZATION_VM_OTHER] = "vm-other",
 632
 633         [VIRTUALIZATION_SYSTEMD_NSPAWN] = "systemd-nspawn",
 634         [VIRTUALIZATION_LXC_LIBVIRT] = "lxc-libvirt",
 635         [VIRTUALIZATION_LXC] = "lxc",
 636         [VIRTUALIZATION_OPENVZ] = "openvz",
 637         [VIRTUALIZATION_DOCKER] = "docker",
 638         [VIRTUALIZATION_RKT] = "rkt",
 639         [VIRTUALIZATION_CONTAINER_OTHER] = "container-other",
 640 };
 641
 642 DEFINE_STRING_TABLE_LOOKUP(virtualization, int);