2 * i386 CPUID helper functions
4 * Copyright (c) 2003 Fabrice Bellard
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
27 #include "qemu-option.h"
28 #include "qemu-config.h"
30 /* feature flags taken from "Intel Processor Identification and the CPUID
31 * Instruction" and AMD's "CPUID Specification". In cases of disagreement
32 * between feature naming conventions, aliases may be added.
34 static const char *feature_name
[] = {
35 "fpu", "vme", "de", "pse",
36 "tsc", "msr", "pae", "mce",
37 "cx8", "apic", NULL
, "sep",
38 "mtrr", "pge", "mca", "cmov",
39 "pat", "pse36", "pn" /* Intel psn */, "clflush" /* Intel clfsh */,
40 NULL
, "ds" /* Intel dts */, "acpi", "mmx",
41 "fxsr", "sse", "sse2", "ss",
42 "ht" /* Intel htt */, "tm", "ia64", "pbe",
44 static const char *ext_feature_name
[] = {
45 "pni|sse3" /* Intel,AMD sse3 */, "pclmuldq", "dtes64", "monitor",
46 "ds_cpl", "vmx", "smx", "est",
47 "tm2", "ssse3", "cid", NULL
,
48 "fma", "cx16", "xtpr", "pdcm",
49 NULL
, NULL
, "dca", "sse4.1|sse4_1",
50 "sse4.2|sse4_2", "x2apic", "movbe", "popcnt",
51 NULL
, "aes", "xsave", "osxsave",
52 "avx", NULL
, NULL
, "hypervisor",
54 static const char *ext2_feature_name
[] = {
55 "fpu", "vme", "de", "pse",
56 "tsc", "msr", "pae", "mce",
57 "cx8" /* AMD CMPXCHG8B */, "apic", NULL
, "syscall",
58 "mtrr", "pge", "mca", "cmov",
59 "pat", "pse36", NULL
, NULL
/* Linux mp */,
60 "nx" /* Intel xd */, NULL
, "mmxext", "mmx",
61 "fxsr", "fxsr_opt" /* AMD ffxsr */, "pdpe1gb" /* AMD Page1GB */, "rdtscp",
62 NULL
, "lm" /* Intel 64 */, "3dnowext", "3dnow",
64 static const char *ext3_feature_name
[] = {
65 "lahf_lm" /* AMD LahfSahf */, "cmp_legacy", "svm", "extapic" /* AMD ExtApicSpace */,
66 "cr8legacy" /* AMD AltMovCr8 */, "abm", "sse4a", "misalignsse",
67 "3dnowprefetch", "osvw", "ibs", "xop",
68 "skinit", "wdt", NULL
, NULL
,
69 "fma4", NULL
, "cvt16", "nodeid_msr",
70 NULL
, NULL
, NULL
, NULL
,
71 NULL
, NULL
, NULL
, NULL
,
72 NULL
, NULL
, NULL
, NULL
,
75 static const char *kvm_feature_name
[] = {
76 "kvmclock", "kvm_nopiodelay", "kvm_mmu", "kvmclock", "kvm_asyncpf", NULL
, NULL
, NULL
,
77 NULL
, NULL
, NULL
, NULL
, NULL
, NULL
, NULL
, NULL
,
78 NULL
, NULL
, NULL
, NULL
, NULL
, NULL
, NULL
, NULL
,
79 NULL
, NULL
, NULL
, NULL
, NULL
, NULL
, NULL
, NULL
,
82 static const char *svm_feature_name
[] = {
83 "npt", "lbrv", "svm_lock", "nrip_save",
84 "tsc_scale", "vmcb_clean", "flushbyasid", "decodeassists",
85 NULL
, NULL
, "pause_filter", NULL
,
86 "pfthreshold", NULL
, NULL
, NULL
,
87 NULL
, NULL
, NULL
, NULL
,
88 NULL
, NULL
, NULL
, NULL
,
89 NULL
, NULL
, NULL
, NULL
,
90 NULL
, NULL
, NULL
, NULL
,
93 /* collects per-function cpuid data
95 typedef struct model_features_t
{
99 const char **flag_names
;
104 int enforce_cpuid
= 0;
106 void host_cpuid(uint32_t function
, uint32_t count
,
107 uint32_t *eax
, uint32_t *ebx
, uint32_t *ecx
, uint32_t *edx
)
109 #if defined(CONFIG_KVM)
114 : "=a"(vec
[0]), "=b"(vec
[1]),
115 "=c"(vec
[2]), "=d"(vec
[3])
116 : "0"(function
), "c"(count
) : "cc");
118 asm volatile("pusha \n\t"
120 "mov %%eax, 0(%2) \n\t"
121 "mov %%ebx, 4(%2) \n\t"
122 "mov %%ecx, 8(%2) \n\t"
123 "mov %%edx, 12(%2) \n\t"
125 : : "a"(function
), "c"(count
), "S"(vec
)
140 #define iswhite(c) ((c) && ((c) <= ' ' || '~' < (c)))
142 /* general substring compare of *[s1..e1) and *[s2..e2). sx is start of
143 * a substring. ex if !NULL points to the first char after a substring,
144 * otherwise the string is assumed to sized by a terminating nul.
145 * Return lexical ordering of *s1:*s2.
147 static int sstrcmp(const char *s1
, const char *e1
, const char *s2
,
151 if (!*s1
|| !*s2
|| *s1
!= *s2
)
154 if (s1
== e1
&& s2
== e2
)
163 /* compare *[s..e) to *altstr. *altstr may be a simple string or multiple
164 * '|' delimited (possibly empty) strings in which case search for a match
165 * within the alternatives proceeds left to right. Return 0 for success,
166 * non-zero otherwise.
168 static int altcmp(const char *s
, const char *e
, const char *altstr
)
172 for (q
= p
= altstr
; ; ) {
173 while (*p
&& *p
!= '|')
175 if ((q
== p
&& !*s
) || (q
!= p
&& !sstrcmp(s
, e
, q
, p
)))
184 /* search featureset for flag *[s..e), if found set corresponding bit in
185 * *pval and return true, otherwise return false
187 static bool lookup_feature(uint32_t *pval
, const char *s
, const char *e
,
188 const char **featureset
)
194 for (mask
= 1, ppc
= featureset
; mask
; mask
<<= 1, ++ppc
) {
195 if (*ppc
&& !altcmp(s
, e
, *ppc
)) {
203 static void add_flagname_to_bitmaps(const char *flagname
, uint32_t *features
,
204 uint32_t *ext_features
,
205 uint32_t *ext2_features
,
206 uint32_t *ext3_features
,
207 uint32_t *kvm_features
,
208 uint32_t *svm_features
)
210 if (!lookup_feature(features
, flagname
, NULL
, feature_name
) &&
211 !lookup_feature(ext_features
, flagname
, NULL
, ext_feature_name
) &&
212 !lookup_feature(ext2_features
, flagname
, NULL
, ext2_feature_name
) &&
213 !lookup_feature(ext3_features
, flagname
, NULL
, ext3_feature_name
) &&
214 !lookup_feature(kvm_features
, flagname
, NULL
, kvm_feature_name
) &&
215 !lookup_feature(svm_features
, flagname
, NULL
, svm_feature_name
))
216 fprintf(stderr
, "CPU feature %s not found\n", flagname
);
219 typedef struct x86_def_t
{
220 struct x86_def_t
*next
;
223 uint32_t vendor1
, vendor2
, vendor3
;
228 uint32_t features
, ext_features
, ext2_features
, ext3_features
;
229 uint32_t kvm_features
, svm_features
;
234 /* Store the results of Centaur's CPUID instructions */
235 uint32_t ext4_features
;
239 #define I486_FEATURES (CPUID_FP87 | CPUID_VME | CPUID_PSE)
240 #define PENTIUM_FEATURES (I486_FEATURES | CPUID_DE | CPUID_TSC | \
241 CPUID_MSR | CPUID_MCE | CPUID_CX8 | CPUID_MMX | CPUID_APIC)
242 #define PENTIUM2_FEATURES (PENTIUM_FEATURES | CPUID_PAE | CPUID_SEP | \
243 CPUID_MTRR | CPUID_PGE | CPUID_MCA | CPUID_CMOV | CPUID_PAT | \
244 CPUID_PSE36 | CPUID_FXSR)
245 #define PENTIUM3_FEATURES (PENTIUM2_FEATURES | CPUID_SSE)
246 #define PPRO_FEATURES (CPUID_FP87 | CPUID_DE | CPUID_PSE | CPUID_TSC | \
247 CPUID_MSR | CPUID_MCE | CPUID_CX8 | CPUID_PGE | CPUID_CMOV | \
248 CPUID_PAT | CPUID_FXSR | CPUID_MMX | CPUID_SSE | CPUID_SSE2 | \
249 CPUID_PAE | CPUID_SEP | CPUID_APIC)
250 #define EXT2_FEATURE_MASK 0x0183F3FF
252 #define TCG_FEATURES (CPUID_FP87 | CPUID_PSE | CPUID_TSC | CPUID_MSR | \
253 CPUID_PAE | CPUID_MCE | CPUID_CX8 | CPUID_APIC | CPUID_SEP | \
254 CPUID_MTRR | CPUID_PGE | CPUID_MCA | CPUID_CMOV | CPUID_PAT | \
255 CPUID_PSE36 | CPUID_CLFLUSH | CPUID_ACPI | CPUID_MMX | \
256 CPUID_FXSR | CPUID_SSE | CPUID_SSE2 | CPUID_SS)
257 /* partly implemented:
258 CPUID_MTRR, CPUID_MCA, CPUID_CLFLUSH (needed for Win64)
259 CPUID_PSE36 (needed for Solaris) */
261 CPUID_VME, CPUID_DTS, CPUID_SS, CPUID_HT, CPUID_TM, CPUID_PBE */
262 #define TCG_EXT_FEATURES (CPUID_EXT_SSE3 | CPUID_EXT_MONITOR | \
263 CPUID_EXT_CX16 | CPUID_EXT_POPCNT | \
264 CPUID_EXT_HYPERVISOR)
266 CPUID_EXT_DTES64, CPUID_EXT_DSCPL, CPUID_EXT_VMX, CPUID_EXT_EST,
267 CPUID_EXT_TM2, CPUID_EXT_XTPR, CPUID_EXT_PDCM, CPUID_EXT_XSAVE */
268 #define TCG_EXT2_FEATURES ((TCG_FEATURES & EXT2_FEATURE_MASK) | \
269 CPUID_EXT2_NX | CPUID_EXT2_MMXEXT | CPUID_EXT2_RDTSCP | \
270 CPUID_EXT2_3DNOW | CPUID_EXT2_3DNOWEXT)
272 CPUID_EXT2_PDPE1GB */
273 #define TCG_EXT3_FEATURES (CPUID_EXT3_LAHF_LM | CPUID_EXT3_SVM | \
274 CPUID_EXT3_CR8LEG | CPUID_EXT3_ABM | CPUID_EXT3_SSE4A)
275 #define TCG_SVM_FEATURES 0
277 /* maintains list of cpu model definitions
279 static x86_def_t
*x86_defs
= {NULL
};
281 /* built-in cpu model definitions (deprecated)
283 static x86_def_t builtin_x86_defs
[] = {
287 .vendor1
= CPUID_VENDOR_AMD_1
,
288 .vendor2
= CPUID_VENDOR_AMD_2
,
289 .vendor3
= CPUID_VENDOR_AMD_3
,
293 .features
= PPRO_FEATURES
|
294 CPUID_MTRR
| CPUID_CLFLUSH
| CPUID_MCA
|
296 .ext_features
= CPUID_EXT_SSE3
| CPUID_EXT_CX16
| CPUID_EXT_POPCNT
,
297 .ext2_features
= (PPRO_FEATURES
& EXT2_FEATURE_MASK
) |
298 CPUID_EXT2_LM
| CPUID_EXT2_SYSCALL
| CPUID_EXT2_NX
,
299 .ext3_features
= CPUID_EXT3_LAHF_LM
| CPUID_EXT3_SVM
|
300 CPUID_EXT3_ABM
| CPUID_EXT3_SSE4A
,
301 .xlevel
= 0x8000000A,
302 .model_id
= "QEMU Virtual CPU version " QEMU_VERSION
,
307 .vendor1
= CPUID_VENDOR_AMD_1
,
308 .vendor2
= CPUID_VENDOR_AMD_2
,
309 .vendor3
= CPUID_VENDOR_AMD_3
,
313 .features
= PPRO_FEATURES
|
314 CPUID_MTRR
| CPUID_CLFLUSH
| CPUID_MCA
|
315 CPUID_PSE36
| CPUID_VME
| CPUID_HT
,
316 .ext_features
= CPUID_EXT_SSE3
| CPUID_EXT_MONITOR
| CPUID_EXT_CX16
|
318 .ext2_features
= (PPRO_FEATURES
& EXT2_FEATURE_MASK
) |
319 CPUID_EXT2_LM
| CPUID_EXT2_SYSCALL
| CPUID_EXT2_NX
|
320 CPUID_EXT2_3DNOW
| CPUID_EXT2_3DNOWEXT
| CPUID_EXT2_MMXEXT
|
321 CPUID_EXT2_FFXSR
| CPUID_EXT2_PDPE1GB
| CPUID_EXT2_RDTSCP
,
322 /* Missing: CPUID_EXT3_CMP_LEG, CPUID_EXT3_EXTAPIC,
324 CPUID_EXT3_MISALIGNSSE, CPUID_EXT3_3DNOWPREFETCH,
325 CPUID_EXT3_OSVW, CPUID_EXT3_IBS */
326 .ext3_features
= CPUID_EXT3_LAHF_LM
| CPUID_EXT3_SVM
|
327 CPUID_EXT3_ABM
| CPUID_EXT3_SSE4A
,
328 .svm_features
= CPUID_SVM_NPT
| CPUID_SVM_LBRV
,
329 .xlevel
= 0x8000001A,
330 .model_id
= "AMD Phenom(tm) 9550 Quad-Core Processor"
338 .features
= PPRO_FEATURES
|
339 CPUID_MTRR
| CPUID_CLFLUSH
| CPUID_MCA
|
340 CPUID_PSE36
| CPUID_VME
| CPUID_DTS
| CPUID_ACPI
| CPUID_SS
|
341 CPUID_HT
| CPUID_TM
| CPUID_PBE
,
342 .ext_features
= CPUID_EXT_SSE3
| CPUID_EXT_MONITOR
| CPUID_EXT_SSSE3
|
343 CPUID_EXT_DTES64
| CPUID_EXT_DSCPL
| CPUID_EXT_VMX
| CPUID_EXT_EST
|
344 CPUID_EXT_TM2
| CPUID_EXT_CX16
| CPUID_EXT_XTPR
| CPUID_EXT_PDCM
,
345 .ext2_features
= CPUID_EXT2_LM
| CPUID_EXT2_SYSCALL
| CPUID_EXT2_NX
,
346 .ext3_features
= CPUID_EXT3_LAHF_LM
,
347 .xlevel
= 0x80000008,
348 .model_id
= "Intel(R) Core(TM)2 Duo CPU T7700 @ 2.40GHz",
353 .vendor1
= CPUID_VENDOR_INTEL_1
,
354 .vendor2
= CPUID_VENDOR_INTEL_2
,
355 .vendor3
= CPUID_VENDOR_INTEL_3
,
359 /* Missing: CPUID_VME, CPUID_HT */
360 .features
= PPRO_FEATURES
|
361 CPUID_MTRR
| CPUID_CLFLUSH
| CPUID_MCA
|
363 /* Missing: CPUID_EXT_POPCNT, CPUID_EXT_MONITOR */
364 .ext_features
= CPUID_EXT_SSE3
| CPUID_EXT_CX16
,
365 /* Missing: CPUID_EXT2_PDPE1GB, CPUID_EXT2_RDTSCP */
366 .ext2_features
= (PPRO_FEATURES
& EXT2_FEATURE_MASK
) |
367 CPUID_EXT2_LM
| CPUID_EXT2_SYSCALL
| CPUID_EXT2_NX
,
368 /* Missing: CPUID_EXT3_LAHF_LM, CPUID_EXT3_CMP_LEG, CPUID_EXT3_EXTAPIC,
369 CPUID_EXT3_CR8LEG, CPUID_EXT3_ABM, CPUID_EXT3_SSE4A,
370 CPUID_EXT3_MISALIGNSSE, CPUID_EXT3_3DNOWPREFETCH,
371 CPUID_EXT3_OSVW, CPUID_EXT3_IBS, CPUID_EXT3_SVM */
373 .xlevel
= 0x80000008,
374 .model_id
= "Common KVM processor"
382 .features
= PPRO_FEATURES
,
383 .ext_features
= CPUID_EXT_SSE3
| CPUID_EXT_POPCNT
,
384 .xlevel
= 0x80000004,
385 .model_id
= "QEMU Virtual CPU version " QEMU_VERSION
,
393 .features
= PPRO_FEATURES
|
394 CPUID_MTRR
| CPUID_CLFLUSH
| CPUID_MCA
| CPUID_PSE36
,
395 .ext_features
= CPUID_EXT_SSE3
,
396 .ext2_features
= PPRO_FEATURES
& EXT2_FEATURE_MASK
,
398 .xlevel
= 0x80000008,
399 .model_id
= "Common 32-bit KVM processor"
407 .features
= PPRO_FEATURES
| CPUID_VME
|
408 CPUID_MTRR
| CPUID_CLFLUSH
| CPUID_MCA
| CPUID_DTS
| CPUID_ACPI
|
409 CPUID_SS
| CPUID_HT
| CPUID_TM
| CPUID_PBE
,
410 .ext_features
= CPUID_EXT_SSE3
| CPUID_EXT_MONITOR
| CPUID_EXT_VMX
|
411 CPUID_EXT_EST
| CPUID_EXT_TM2
| CPUID_EXT_XTPR
| CPUID_EXT_PDCM
,
412 .ext2_features
= CPUID_EXT2_NX
,
413 .xlevel
= 0x80000008,
414 .model_id
= "Genuine Intel(R) CPU T2600 @ 2.16GHz",
422 .features
= I486_FEATURES
,
431 .features
= PENTIUM_FEATURES
,
440 .features
= PENTIUM2_FEATURES
,
449 .features
= PENTIUM3_FEATURES
,
455 .vendor1
= CPUID_VENDOR_AMD_1
,
456 .vendor2
= CPUID_VENDOR_AMD_2
,
457 .vendor3
= CPUID_VENDOR_AMD_3
,
461 .features
= PPRO_FEATURES
| CPUID_PSE36
| CPUID_VME
| CPUID_MTRR
| CPUID_MCA
,
462 .ext2_features
= (PPRO_FEATURES
& EXT2_FEATURE_MASK
) | CPUID_EXT2_MMXEXT
| CPUID_EXT2_3DNOW
| CPUID_EXT2_3DNOWEXT
,
463 .xlevel
= 0x80000008,
464 /* XXX: put another string ? */
465 .model_id
= "QEMU Virtual CPU version " QEMU_VERSION
,
469 /* original is on level 10 */
474 .features
= PPRO_FEATURES
|
475 CPUID_MTRR
| CPUID_CLFLUSH
| CPUID_MCA
| CPUID_VME
| CPUID_DTS
|
476 CPUID_ACPI
| CPUID_SS
| CPUID_HT
| CPUID_TM
| CPUID_PBE
,
477 /* Some CPUs got no CPUID_SEP */
478 .ext_features
= CPUID_EXT_SSE3
| CPUID_EXT_MONITOR
| CPUID_EXT_SSSE3
|
479 CPUID_EXT_DSCPL
| CPUID_EXT_EST
| CPUID_EXT_TM2
| CPUID_EXT_XTPR
,
480 .ext2_features
= (PPRO_FEATURES
& EXT2_FEATURE_MASK
) | CPUID_EXT2_NX
,
481 .ext3_features
= CPUID_EXT3_LAHF_LM
,
482 .xlevel
= 0x8000000A,
483 .model_id
= "Intel(R) Atom(TM) CPU N270 @ 1.60GHz",
487 static int cpu_x86_fill_model_id(char *str
)
489 uint32_t eax
= 0, ebx
= 0, ecx
= 0, edx
= 0;
492 for (i
= 0; i
< 3; i
++) {
493 host_cpuid(0x80000002 + i
, 0, &eax
, &ebx
, &ecx
, &edx
);
494 memcpy(str
+ i
* 16 + 0, &eax
, 4);
495 memcpy(str
+ i
* 16 + 4, &ebx
, 4);
496 memcpy(str
+ i
* 16 + 8, &ecx
, 4);
497 memcpy(str
+ i
* 16 + 12, &edx
, 4);
502 static int cpu_x86_fill_host(x86_def_t
*x86_cpu_def
)
504 uint32_t eax
= 0, ebx
= 0, ecx
= 0, edx
= 0;
506 x86_cpu_def
->name
= "host";
507 host_cpuid(0x0, 0, &eax
, &ebx
, &ecx
, &edx
);
508 x86_cpu_def
->level
= eax
;
509 x86_cpu_def
->vendor1
= ebx
;
510 x86_cpu_def
->vendor2
= edx
;
511 x86_cpu_def
->vendor3
= ecx
;
513 host_cpuid(0x1, 0, &eax
, &ebx
, &ecx
, &edx
);
514 x86_cpu_def
->family
= ((eax
>> 8) & 0x0F) + ((eax
>> 20) & 0xFF);
515 x86_cpu_def
->model
= ((eax
>> 4) & 0x0F) | ((eax
& 0xF0000) >> 12);
516 x86_cpu_def
->stepping
= eax
& 0x0F;
517 x86_cpu_def
->ext_features
= ecx
;
518 x86_cpu_def
->features
= edx
;
520 host_cpuid(0x80000000, 0, &eax
, &ebx
, &ecx
, &edx
);
521 x86_cpu_def
->xlevel
= eax
;
523 host_cpuid(0x80000001, 0, &eax
, &ebx
, &ecx
, &edx
);
524 x86_cpu_def
->ext2_features
= edx
;
525 x86_cpu_def
->ext3_features
= ecx
;
526 cpu_x86_fill_model_id(x86_cpu_def
->model_id
);
527 x86_cpu_def
->vendor_override
= 0;
529 /* Call Centaur's CPUID instruction. */
530 if (x86_cpu_def
->vendor1
== CPUID_VENDOR_VIA_1
&&
531 x86_cpu_def
->vendor2
== CPUID_VENDOR_VIA_2
&&
532 x86_cpu_def
->vendor3
== CPUID_VENDOR_VIA_3
) {
533 host_cpuid(0xC0000000, 0, &eax
, &ebx
, &ecx
, &edx
);
534 if (eax
>= 0xC0000001) {
535 /* Support VIA max extended level */
536 x86_cpu_def
->xlevel2
= eax
;
537 host_cpuid(0xC0000001, 0, &eax
, &ebx
, &ecx
, &edx
);
538 x86_cpu_def
->ext4_features
= edx
;
543 * Every SVM feature requires emulation support in KVM - so we can't just
544 * read the host features here. KVM might even support SVM features not
545 * available on the host hardware. Just set all bits and mask out the
546 * unsupported ones later.
548 x86_cpu_def
->svm_features
= -1;
553 static int unavailable_host_feature(struct model_features_t
*f
, uint32_t mask
)
557 for (i
= 0; i
< 32; ++i
)
559 fprintf(stderr
, "warning: host cpuid %04x_%04x lacks requested"
560 " flag '%s' [0x%08x]\n",
561 f
->cpuid
>> 16, f
->cpuid
& 0xffff,
562 f
->flag_names
[i
] ? f
->flag_names
[i
] : "[reserved]", mask
);
568 /* best effort attempt to inform user requested cpu flags aren't making
569 * their way to the guest. Note: ft[].check_feat ideally should be
570 * specified via a guest_def field to suppress report of extraneous flags.
572 static int check_features_against_host(x86_def_t
*guest_def
)
577 struct model_features_t ft
[] = {
578 {&guest_def
->features
, &host_def
.features
,
579 ~0, feature_name
, 0x00000000},
580 {&guest_def
->ext_features
, &host_def
.ext_features
,
581 ~CPUID_EXT_HYPERVISOR
, ext_feature_name
, 0x00000001},
582 {&guest_def
->ext2_features
, &host_def
.ext2_features
,
583 ~PPRO_FEATURES
, ext2_feature_name
, 0x80000000},
584 {&guest_def
->ext3_features
, &host_def
.ext3_features
,
585 ~CPUID_EXT3_SVM
, ext3_feature_name
, 0x80000001}};
587 cpu_x86_fill_host(&host_def
);
588 for (rv
= 0, i
= 0; i
< ARRAY_SIZE(ft
); ++i
)
589 for (mask
= 1; mask
; mask
<<= 1)
590 if (ft
[i
].check_feat
& mask
&& *ft
[i
].guest_feat
& mask
&&
591 !(*ft
[i
].host_feat
& mask
)) {
592 unavailable_host_feature(&ft
[i
], mask
);
598 static int cpu_x86_find_by_name(x86_def_t
*x86_cpu_def
, const char *cpu_model
)
603 char *s
= strdup(cpu_model
);
604 char *featurestr
, *name
= strtok(s
, ",");
605 /* Features to be added*/
606 uint32_t plus_features
= 0, plus_ext_features
= 0;
607 uint32_t plus_ext2_features
= 0, plus_ext3_features
= 0;
608 uint32_t plus_kvm_features
= 0, plus_svm_features
= 0;
609 /* Features to be removed */
610 uint32_t minus_features
= 0, minus_ext_features
= 0;
611 uint32_t minus_ext2_features
= 0, minus_ext3_features
= 0;
612 uint32_t minus_kvm_features
= 0, minus_svm_features
= 0;
615 for (def
= x86_defs
; def
; def
= def
->next
)
616 if (!strcmp(name
, def
->name
))
618 if (kvm_enabled() && strcmp(name
, "host") == 0) {
619 cpu_x86_fill_host(x86_cpu_def
);
623 memcpy(x86_cpu_def
, def
, sizeof(*def
));
626 plus_kvm_features
= ~0; /* not supported bits will be filtered out later */
628 add_flagname_to_bitmaps("hypervisor", &plus_features
,
629 &plus_ext_features
, &plus_ext2_features
, &plus_ext3_features
,
630 &plus_kvm_features
, &plus_svm_features
);
632 featurestr
= strtok(NULL
, ",");
636 if (featurestr
[0] == '+') {
637 add_flagname_to_bitmaps(featurestr
+ 1, &plus_features
,
638 &plus_ext_features
, &plus_ext2_features
,
639 &plus_ext3_features
, &plus_kvm_features
,
641 } else if (featurestr
[0] == '-') {
642 add_flagname_to_bitmaps(featurestr
+ 1, &minus_features
,
643 &minus_ext_features
, &minus_ext2_features
,
644 &minus_ext3_features
, &minus_kvm_features
,
645 &minus_svm_features
);
646 } else if ((val
= strchr(featurestr
, '='))) {
648 if (!strcmp(featurestr
, "family")) {
650 numvalue
= strtoul(val
, &err
, 0);
652 fprintf(stderr
, "bad numerical value %s\n", val
);
655 x86_cpu_def
->family
= numvalue
;
656 } else if (!strcmp(featurestr
, "model")) {
658 numvalue
= strtoul(val
, &err
, 0);
659 if (!*val
|| *err
|| numvalue
> 0xff) {
660 fprintf(stderr
, "bad numerical value %s\n", val
);
663 x86_cpu_def
->model
= numvalue
;
664 } else if (!strcmp(featurestr
, "stepping")) {
666 numvalue
= strtoul(val
, &err
, 0);
667 if (!*val
|| *err
|| numvalue
> 0xf) {
668 fprintf(stderr
, "bad numerical value %s\n", val
);
671 x86_cpu_def
->stepping
= numvalue
;
672 } else if (!strcmp(featurestr
, "level")) {
674 numvalue
= strtoul(val
, &err
, 0);
676 fprintf(stderr
, "bad numerical value %s\n", val
);
679 x86_cpu_def
->level
= numvalue
;
680 } else if (!strcmp(featurestr
, "xlevel")) {
682 numvalue
= strtoul(val
, &err
, 0);
684 fprintf(stderr
, "bad numerical value %s\n", val
);
687 if (numvalue
< 0x80000000) {
688 numvalue
+= 0x80000000;
690 x86_cpu_def
->xlevel
= numvalue
;
691 } else if (!strcmp(featurestr
, "vendor")) {
692 if (strlen(val
) != 12) {
693 fprintf(stderr
, "vendor string must be 12 chars long\n");
696 x86_cpu_def
->vendor1
= 0;
697 x86_cpu_def
->vendor2
= 0;
698 x86_cpu_def
->vendor3
= 0;
699 for(i
= 0; i
< 4; i
++) {
700 x86_cpu_def
->vendor1
|= ((uint8_t)val
[i
]) << (8 * i
);
701 x86_cpu_def
->vendor2
|= ((uint8_t)val
[i
+ 4]) << (8 * i
);
702 x86_cpu_def
->vendor3
|= ((uint8_t)val
[i
+ 8]) << (8 * i
);
704 x86_cpu_def
->vendor_override
= 1;
705 } else if (!strcmp(featurestr
, "model_id")) {
706 pstrcpy(x86_cpu_def
->model_id
, sizeof(x86_cpu_def
->model_id
),
708 } else if (!strcmp(featurestr
, "tsc_freq")) {
712 tsc_freq
= strtosz_suffix_unit(val
, &err
,
713 STRTOSZ_DEFSUFFIX_B
, 1000);
715 fprintf(stderr
, "bad numerical value %s\n", val
);
718 x86_cpu_def
->tsc_khz
= tsc_freq
/ 1000;
720 fprintf(stderr
, "unrecognized feature %s\n", featurestr
);
723 } else if (!strcmp(featurestr
, "check")) {
725 } else if (!strcmp(featurestr
, "enforce")) {
726 check_cpuid
= enforce_cpuid
= 1;
728 fprintf(stderr
, "feature string `%s' not in format (+feature|-feature|feature=xyz)\n", featurestr
);
731 featurestr
= strtok(NULL
, ",");
733 x86_cpu_def
->features
|= plus_features
;
734 x86_cpu_def
->ext_features
|= plus_ext_features
;
735 x86_cpu_def
->ext2_features
|= plus_ext2_features
;
736 x86_cpu_def
->ext3_features
|= plus_ext3_features
;
737 x86_cpu_def
->kvm_features
|= plus_kvm_features
;
738 x86_cpu_def
->svm_features
|= plus_svm_features
;
739 x86_cpu_def
->features
&= ~minus_features
;
740 x86_cpu_def
->ext_features
&= ~minus_ext_features
;
741 x86_cpu_def
->ext2_features
&= ~minus_ext2_features
;
742 x86_cpu_def
->ext3_features
&= ~minus_ext3_features
;
743 x86_cpu_def
->kvm_features
&= ~minus_kvm_features
;
744 x86_cpu_def
->svm_features
&= ~minus_svm_features
;
746 if (check_features_against_host(x86_cpu_def
) && enforce_cpuid
)
757 /* generate a composite string into buf of all cpuid names in featureset
758 * selected by fbits. indicate truncation at bufsize in the event of overflow.
759 * if flags, suppress names undefined in featureset.
761 static void listflags(char *buf
, int bufsize
, uint32_t fbits
,
762 const char **featureset
, uint32_t flags
)
764 const char **p
= &featureset
[31];
768 b
= 4 <= bufsize
? buf
+ (bufsize
-= 3) - 1 : NULL
;
770 for (q
= buf
, bit
= 31; fbits
&& bufsize
; --p
, fbits
&= ~(1 << bit
), --bit
)
771 if (fbits
& 1 << bit
&& (*p
|| !flags
)) {
773 nc
= snprintf(q
, bufsize
, "%s%s", q
== buf
? "" : " ", *p
);
775 nc
= snprintf(q
, bufsize
, "%s[%d]", q
== buf
? "" : " ", bit
);
778 memcpy(b
, "...", sizeof("..."));
787 /* generate CPU information:
788 * -? list model names
789 * -?model list model names/IDs
790 * -?dump output all model (x86_def_t) data
791 * -?cpuid list all recognized cpuid flag names
793 void x86_cpu_list(FILE *f
, fprintf_function cpu_fprintf
, const char *optarg
)
795 unsigned char model
= !strcmp("?model", optarg
);
796 unsigned char dump
= !strcmp("?dump", optarg
);
797 unsigned char cpuid
= !strcmp("?cpuid", optarg
);
802 (*cpu_fprintf
)(f
, "Recognized CPUID flags:\n");
803 listflags(buf
, sizeof (buf
), (uint32_t)~0, feature_name
, 1);
804 (*cpu_fprintf
)(f
, " f_edx: %s\n", buf
);
805 listflags(buf
, sizeof (buf
), (uint32_t)~0, ext_feature_name
, 1);
806 (*cpu_fprintf
)(f
, " f_ecx: %s\n", buf
);
807 listflags(buf
, sizeof (buf
), (uint32_t)~0, ext2_feature_name
, 1);
808 (*cpu_fprintf
)(f
, " extf_edx: %s\n", buf
);
809 listflags(buf
, sizeof (buf
), (uint32_t)~0, ext3_feature_name
, 1);
810 (*cpu_fprintf
)(f
, " extf_ecx: %s\n", buf
);
813 for (def
= x86_defs
; def
; def
= def
->next
) {
814 snprintf(buf
, sizeof (buf
), def
->flags
? "[%s]": "%s", def
->name
);
816 (*cpu_fprintf
)(f
, "x86 %16s %-48s\n", buf
, def
->model_id
);
818 (*cpu_fprintf
)(f
, "x86 %16s\n", buf
);
821 memcpy(buf
, &def
->vendor1
, sizeof (def
->vendor1
));
822 memcpy(buf
+ 4, &def
->vendor2
, sizeof (def
->vendor2
));
823 memcpy(buf
+ 8, &def
->vendor3
, sizeof (def
->vendor3
));
826 " family %d model %d stepping %d level %d xlevel 0x%x"
828 def
->family
, def
->model
, def
->stepping
, def
->level
,
830 listflags(buf
, sizeof (buf
), def
->features
, feature_name
, 0);
831 (*cpu_fprintf
)(f
, " feature_edx %08x (%s)\n", def
->features
,
833 listflags(buf
, sizeof (buf
), def
->ext_features
, ext_feature_name
,
835 (*cpu_fprintf
)(f
, " feature_ecx %08x (%s)\n", def
->ext_features
,
837 listflags(buf
, sizeof (buf
), def
->ext2_features
, ext2_feature_name
,
839 (*cpu_fprintf
)(f
, " extfeature_edx %08x (%s)\n",
840 def
->ext2_features
, buf
);
841 listflags(buf
, sizeof (buf
), def
->ext3_features
, ext3_feature_name
,
843 (*cpu_fprintf
)(f
, " extfeature_ecx %08x (%s)\n",
844 def
->ext3_features
, buf
);
845 (*cpu_fprintf
)(f
, "\n");
849 (*cpu_fprintf
)(f
, "x86 %16s\n", "[host]");
853 int cpu_x86_register (CPUX86State
*env
, const char *cpu_model
)
855 x86_def_t def1
, *def
= &def1
;
857 memset(def
, 0, sizeof(*def
));
859 if (cpu_x86_find_by_name(def
, cpu_model
) < 0)
862 env
->cpuid_vendor1
= def
->vendor1
;
863 env
->cpuid_vendor2
= def
->vendor2
;
864 env
->cpuid_vendor3
= def
->vendor3
;
866 env
->cpuid_vendor1
= CPUID_VENDOR_INTEL_1
;
867 env
->cpuid_vendor2
= CPUID_VENDOR_INTEL_2
;
868 env
->cpuid_vendor3
= CPUID_VENDOR_INTEL_3
;
870 env
->cpuid_vendor_override
= def
->vendor_override
;
871 env
->cpuid_level
= def
->level
;
872 if (def
->family
> 0x0f)
873 env
->cpuid_version
= 0xf00 | ((def
->family
- 0x0f) << 20);
875 env
->cpuid_version
= def
->family
<< 8;
876 env
->cpuid_version
|= ((def
->model
& 0xf) << 4) | ((def
->model
>> 4) << 16);
877 env
->cpuid_version
|= def
->stepping
;
878 env
->cpuid_features
= def
->features
;
879 env
->cpuid_ext_features
= def
->ext_features
;
880 env
->cpuid_ext2_features
= def
->ext2_features
;
881 env
->cpuid_ext3_features
= def
->ext3_features
;
882 env
->cpuid_xlevel
= def
->xlevel
;
883 env
->cpuid_kvm_features
= def
->kvm_features
;
884 env
->cpuid_svm_features
= def
->svm_features
;
885 env
->cpuid_ext4_features
= def
->ext4_features
;
886 env
->cpuid_xlevel2
= def
->xlevel2
;
887 env
->tsc_khz
= def
->tsc_khz
;
888 if (!kvm_enabled()) {
889 env
->cpuid_features
&= TCG_FEATURES
;
890 env
->cpuid_ext_features
&= TCG_EXT_FEATURES
;
891 env
->cpuid_ext2_features
&= (TCG_EXT2_FEATURES
893 | CPUID_EXT2_SYSCALL
| CPUID_EXT2_LM
896 env
->cpuid_ext3_features
&= TCG_EXT3_FEATURES
;
897 env
->cpuid_svm_features
&= TCG_SVM_FEATURES
;
900 const char *model_id
= def
->model_id
;
904 len
= strlen(model_id
);
905 for(i
= 0; i
< 48; i
++) {
909 c
= (uint8_t)model_id
[i
];
910 env
->cpuid_model
[i
>> 2] |= c
<< (8 * (i
& 3));
916 #if !defined(CONFIG_USER_ONLY)
917 /* copy vendor id string to 32 bit register, nul pad as needed
919 static void cpyid(const char *s
, uint32_t *id
)
921 char *d
= (char *)id
;
924 for (i
= sizeof (*id
); i
--; )
925 *d
++ = *s
? *s
++ : '\0';
928 /* interpret radix and convert from string to arbitrary scalar,
929 * otherwise flag failure
931 #define setscalar(pval, str, perr) \
936 ul = strtoul(str, &pend, 0); \
937 *str && !*pend ? (*pval = ul) : (*perr = 1); \
940 /* map cpuid options to feature bits, otherwise return failure
941 * (option tags in *str are delimited by whitespace)
943 static void setfeatures(uint32_t *pval
, const char *str
,
944 const char **featureset
, int *perr
)
948 for (q
= p
= str
; *p
|| *q
; q
= p
) {
951 while (*p
&& !iswhite(*p
))
955 if (!lookup_feature(pval
, q
, p
, featureset
)) {
956 fprintf(stderr
, "error: feature \"%.*s\" not available in set\n",
964 /* map config file options to x86_def_t form
966 static int cpudef_setfield(const char *name
, const char *str
, void *opaque
)
968 x86_def_t
*def
= opaque
;
971 if (!strcmp(name
, "name")) {
972 def
->name
= strdup(str
);
973 } else if (!strcmp(name
, "model_id")) {
974 strncpy(def
->model_id
, str
, sizeof (def
->model_id
));
975 } else if (!strcmp(name
, "level")) {
976 setscalar(&def
->level
, str
, &err
)
977 } else if (!strcmp(name
, "vendor")) {
978 cpyid(&str
[0], &def
->vendor1
);
979 cpyid(&str
[4], &def
->vendor2
);
980 cpyid(&str
[8], &def
->vendor3
);
981 } else if (!strcmp(name
, "family")) {
982 setscalar(&def
->family
, str
, &err
)
983 } else if (!strcmp(name
, "model")) {
984 setscalar(&def
->model
, str
, &err
)
985 } else if (!strcmp(name
, "stepping")) {
986 setscalar(&def
->stepping
, str
, &err
)
987 } else if (!strcmp(name
, "feature_edx")) {
988 setfeatures(&def
->features
, str
, feature_name
, &err
);
989 } else if (!strcmp(name
, "feature_ecx")) {
990 setfeatures(&def
->ext_features
, str
, ext_feature_name
, &err
);
991 } else if (!strcmp(name
, "extfeature_edx")) {
992 setfeatures(&def
->ext2_features
, str
, ext2_feature_name
, &err
);
993 } else if (!strcmp(name
, "extfeature_ecx")) {
994 setfeatures(&def
->ext3_features
, str
, ext3_feature_name
, &err
);
995 } else if (!strcmp(name
, "xlevel")) {
996 setscalar(&def
->xlevel
, str
, &err
)
998 fprintf(stderr
, "error: unknown option [%s = %s]\n", name
, str
);
1002 fprintf(stderr
, "error: bad option value [%s = %s]\n", name
, str
);
1008 /* register config file entry as x86_def_t
1010 static int cpudef_register(QemuOpts
*opts
, void *opaque
)
1012 x86_def_t
*def
= g_malloc0(sizeof (x86_def_t
));
1014 qemu_opt_foreach(opts
, cpudef_setfield
, def
, 1);
1015 def
->next
= x86_defs
;
1020 void cpu_clear_apic_feature(CPUX86State
*env
)
1022 env
->cpuid_features
&= ~CPUID_APIC
;
1025 #endif /* !CONFIG_USER_ONLY */
1027 /* register "cpudef" models defined in configuration file. Here we first
1028 * preload any built-in definitions
1030 void x86_cpudef_setup(void)
1034 for (i
= 0; i
< ARRAY_SIZE(builtin_x86_defs
); ++i
) {
1035 builtin_x86_defs
[i
].next
= x86_defs
;
1036 builtin_x86_defs
[i
].flags
= 1;
1037 x86_defs
= &builtin_x86_defs
[i
];
1039 #if !defined(CONFIG_USER_ONLY)
1040 qemu_opts_foreach(qemu_find_opts("cpudef"), cpudef_register
, NULL
, 0);
1044 static void get_cpuid_vendor(CPUX86State
*env
, uint32_t *ebx
,
1045 uint32_t *ecx
, uint32_t *edx
)
1047 *ebx
= env
->cpuid_vendor1
;
1048 *edx
= env
->cpuid_vendor2
;
1049 *ecx
= env
->cpuid_vendor3
;
1051 /* sysenter isn't supported on compatibility mode on AMD, syscall
1052 * isn't supported in compatibility mode on Intel.
1053 * Normally we advertise the actual cpu vendor, but you can override
1054 * this if you want to use KVM's sysenter/syscall emulation
1055 * in compatibility mode and when doing cross vendor migration
1057 if (kvm_enabled() && ! env
->cpuid_vendor_override
) {
1058 host_cpuid(0, 0, NULL
, ebx
, ecx
, edx
);
1062 void cpu_x86_cpuid(CPUX86State
*env
, uint32_t index
, uint32_t count
,
1063 uint32_t *eax
, uint32_t *ebx
,
1064 uint32_t *ecx
, uint32_t *edx
)
1066 /* test if maximum index reached */
1067 if (index
& 0x80000000) {
1068 if (index
> env
->cpuid_xlevel
) {
1069 if (env
->cpuid_xlevel2
> 0) {
1070 /* Handle the Centaur's CPUID instruction. */
1071 if (index
> env
->cpuid_xlevel2
) {
1072 index
= env
->cpuid_xlevel2
;
1073 } else if (index
< 0xC0000000) {
1074 index
= env
->cpuid_xlevel
;
1077 index
= env
->cpuid_xlevel
;
1081 if (index
> env
->cpuid_level
)
1082 index
= env
->cpuid_level
;
1087 *eax
= env
->cpuid_level
;
1088 get_cpuid_vendor(env
, ebx
, ecx
, edx
);
1091 *eax
= env
->cpuid_version
;
1092 *ebx
= (env
->cpuid_apic_id
<< 24) | 8 << 8; /* CLFLUSH size in quad words, Linux wants it. */
1093 *ecx
= env
->cpuid_ext_features
;
1094 *edx
= env
->cpuid_features
;
1095 if (env
->nr_cores
* env
->nr_threads
> 1) {
1096 *ebx
|= (env
->nr_cores
* env
->nr_threads
) << 16;
1097 *edx
|= 1 << 28; /* HTT bit */
1101 /* cache info: needed for Pentium Pro compatibility */
1108 /* cache info: needed for Core compatibility */
1109 if (env
->nr_cores
> 1) {
1110 *eax
= (env
->nr_cores
- 1) << 26;
1115 case 0: /* L1 dcache info */
1121 case 1: /* L1 icache info */
1127 case 2: /* L2 cache info */
1129 if (env
->nr_threads
> 1) {
1130 *eax
|= (env
->nr_threads
- 1) << 14;
1136 default: /* end of info */
1145 /* mwait info: needed for Core compatibility */
1146 *eax
= 0; /* Smallest monitor-line size in bytes */
1147 *ebx
= 0; /* Largest monitor-line size in bytes */
1148 *ecx
= CPUID_MWAIT_EMX
| CPUID_MWAIT_IBE
;
1152 /* Thermal and Power Leaf */
1159 if (kvm_enabled()) {
1160 KVMState
*s
= env
->kvm_state
;
1162 *eax
= kvm_arch_get_supported_cpuid(s
, 0x7, count
, R_EAX
);
1163 *ebx
= kvm_arch_get_supported_cpuid(s
, 0x7, count
, R_EBX
);
1164 *ecx
= kvm_arch_get_supported_cpuid(s
, 0x7, count
, R_ECX
);
1165 *edx
= kvm_arch_get_supported_cpuid(s
, 0x7, count
, R_EDX
);
1174 /* Direct Cache Access Information Leaf */
1175 *eax
= 0; /* Bits 0-31 in DCA_CAP MSR */
1181 /* Architectural Performance Monitoring Leaf */
1188 /* Processor Extended State */
1189 if (!(env
->cpuid_ext_features
& CPUID_EXT_XSAVE
)) {
1196 if (kvm_enabled()) {
1197 KVMState
*s
= env
->kvm_state
;
1199 *eax
= kvm_arch_get_supported_cpuid(s
, 0xd, count
, R_EAX
);
1200 *ebx
= kvm_arch_get_supported_cpuid(s
, 0xd, count
, R_EBX
);
1201 *ecx
= kvm_arch_get_supported_cpuid(s
, 0xd, count
, R_ECX
);
1202 *edx
= kvm_arch_get_supported_cpuid(s
, 0xd, count
, R_EDX
);
1211 *eax
= env
->cpuid_xlevel
;
1212 *ebx
= env
->cpuid_vendor1
;
1213 *edx
= env
->cpuid_vendor2
;
1214 *ecx
= env
->cpuid_vendor3
;
1217 *eax
= env
->cpuid_version
;
1219 *ecx
= env
->cpuid_ext3_features
;
1220 *edx
= env
->cpuid_ext2_features
;
1222 /* The Linux kernel checks for the CMPLegacy bit and
1223 * discards multiple thread information if it is set.
1224 * So dont set it here for Intel to make Linux guests happy.
1226 if (env
->nr_cores
* env
->nr_threads
> 1) {
1227 uint32_t tebx
, tecx
, tedx
;
1228 get_cpuid_vendor(env
, &tebx
, &tecx
, &tedx
);
1229 if (tebx
!= CPUID_VENDOR_INTEL_1
||
1230 tedx
!= CPUID_VENDOR_INTEL_2
||
1231 tecx
!= CPUID_VENDOR_INTEL_3
) {
1232 *ecx
|= 1 << 1; /* CmpLegacy bit */
1239 *eax
= env
->cpuid_model
[(index
- 0x80000002) * 4 + 0];
1240 *ebx
= env
->cpuid_model
[(index
- 0x80000002) * 4 + 1];
1241 *ecx
= env
->cpuid_model
[(index
- 0x80000002) * 4 + 2];
1242 *edx
= env
->cpuid_model
[(index
- 0x80000002) * 4 + 3];
1245 /* cache info (L1 cache) */
1252 /* cache info (L2 cache) */
1259 /* virtual & phys address size in low 2 bytes. */
1260 /* XXX: This value must match the one used in the MMU code. */
1261 if (env
->cpuid_ext2_features
& CPUID_EXT2_LM
) {
1262 /* 64 bit processor */
1263 /* XXX: The physical address space is limited to 42 bits in exec.c. */
1264 *eax
= 0x00003028; /* 48 bits virtual, 40 bits physical */
1266 if (env
->cpuid_features
& CPUID_PSE36
)
1267 *eax
= 0x00000024; /* 36 bits physical */
1269 *eax
= 0x00000020; /* 32 bits physical */
1274 if (env
->nr_cores
* env
->nr_threads
> 1) {
1275 *ecx
|= (env
->nr_cores
* env
->nr_threads
) - 1;
1279 if (env
->cpuid_ext3_features
& CPUID_EXT3_SVM
) {
1280 *eax
= 0x00000001; /* SVM Revision */
1281 *ebx
= 0x00000010; /* nr of ASIDs */
1283 *edx
= env
->cpuid_svm_features
; /* optional features */
1292 *eax
= env
->cpuid_xlevel2
;
1298 /* Support for VIA CPU's CPUID instruction */
1299 *eax
= env
->cpuid_version
;
1302 *edx
= env
->cpuid_ext4_features
;
1307 /* Reserved for the future, and now filled with zero */
1314 /* reserved values: zero */