Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'x86_tdx_for_6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 TDX updates from Dave Hansen:
"Intel Trust Domain updates.
The existing TDX code needs a _bit_ of metadata from the TDX module.
But KVM is going to need a bunch more very shortly. Rework the
interface with the TDX module to be more consistent and handle the new
higher volume.
The TDX module has added a few new features. The first is a promise
not to clobber RBP under any circumstances. Basically the kernel now
will refuse to use any modules that don't have this promise. Second,
enable the new "REDUCE_VE" feature. This ensures that the TDX module
will not send some silly virtualization exceptions that the guest had
no good way to handle anyway.
- Centralize global metadata infrastructure
- Use new TDX module features for exception suppression and RBP
clobbering"
* tag 'x86_tdx_for_6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/virt/tdx: Require the module to assert it has the NO_RBP_MOD mitigation
x86/virt/tdx: Switch to use auto-generated global metadata reading code
x86/virt/tdx: Use dedicated struct members for PAMT entry sizes
x86/virt/tdx: Use auto-generated code to read global metadata
x86/virt/tdx: Start to track all global metadata in one structure
x86/virt/tdx: Rename 'struct tdx_tdmr_sysinfo' to reflect the spec better
x86/tdx: Dump attributes and TD_CTLS on boot
x86/tdx: Disable unnecessary virtualization exceptions
+253
-113
+1
-1
arch/x86/coco/tdx/Makefile
+1
-1
arch/x86/coco/tdx/Makefile
+69
arch/x86/coco/tdx/debug.c
+69
arch/x86/coco/tdx/debug.c
···
1
+
// SPDX-License-Identifier: GPL-2.0
2
+
3
+
#undef pr_fmt
4
+
#define pr_fmt(fmt) "tdx: " fmt
5
+
6
+
#include <linux/array_size.h>
7
+
#include <linux/printk.h>
8
+
#include <asm/tdx.h>
9
+
10
+
#define DEF_TDX_ATTR_NAME(_name) [TDX_ATTR_##_name##_BIT] = __stringify(_name)
11
+
12
+
static __initdata const char *tdx_attributes[] = {
13
+
DEF_TDX_ATTR_NAME(DEBUG),
14
+
DEF_TDX_ATTR_NAME(HGS_PLUS_PROF),
15
+
DEF_TDX_ATTR_NAME(PERF_PROF),
16
+
DEF_TDX_ATTR_NAME(PMT_PROF),
17
+
DEF_TDX_ATTR_NAME(ICSSD),
18
+
DEF_TDX_ATTR_NAME(LASS),
19
+
DEF_TDX_ATTR_NAME(SEPT_VE_DISABLE),
20
+
DEF_TDX_ATTR_NAME(MIGRTABLE),
21
+
DEF_TDX_ATTR_NAME(PKS),
22
+
DEF_TDX_ATTR_NAME(KL),
23
+
DEF_TDX_ATTR_NAME(TPA),
24
+
DEF_TDX_ATTR_NAME(PERFMON),
25
+
};
26
+
27
+
#define DEF_TD_CTLS_NAME(_name) [TD_CTLS_##_name##_BIT] = __stringify(_name)
28
+
29
+
static __initdata const char *tdcs_td_ctls[] = {
30
+
DEF_TD_CTLS_NAME(PENDING_VE_DISABLE),
31
+
DEF_TD_CTLS_NAME(ENUM_TOPOLOGY),
32
+
DEF_TD_CTLS_NAME(VIRT_CPUID2),
33
+
DEF_TD_CTLS_NAME(REDUCE_VE),
34
+
DEF_TD_CTLS_NAME(LOCK),
35
+
};
36
+
37
+
void __init tdx_dump_attributes(u64 td_attr)
38
+
{
39
+
pr_info("Attributes:");
40
+
41
+
for (int i = 0; i < ARRAY_SIZE(tdx_attributes); i++) {
42
+
if (!tdx_attributes[i])
43
+
continue;
44
+
if (td_attr & BIT(i))
45
+
pr_cont(" %s", tdx_attributes[i]);
46
+
td_attr &= ~BIT(i);
47
+
}
48
+
49
+
if (td_attr)
50
+
pr_cont(" unknown:%#llx", td_attr);
51
+
pr_cont("\n");
52
+
53
+
}
54
+
55
+
void __init tdx_dump_td_ctls(u64 td_ctls)
56
+
{
57
+
pr_info("TD_CTLS:");
58
+
59
+
for (int i = 0; i < ARRAY_SIZE(tdcs_td_ctls); i++) {
60
+
if (!tdcs_td_ctls[i])
61
+
continue;
62
+
if (td_ctls & BIT(i))
63
+
pr_cont(" %s", tdcs_td_ctls[i]);
64
+
td_ctls &= ~BIT(i);
65
+
}
66
+
if (td_ctls)
67
+
pr_cont(" unknown:%#llx", td_ctls);
68
+
pr_cont("\n");
69
+
}
+35
-9
arch/x86/coco/tdx/tdx.c
+35
-9
arch/x86/coco/tdx/tdx.c
···
32
32
#define VE_GET_PORT_NUM(e) ((e) >> 16)
33
33
#define VE_IS_IO_STRING(e) ((e) & BIT(4))
34
34
35
-
#define ATTR_DEBUG BIT(0)
36
-
#define ATTR_SEPT_VE_DISABLE BIT(28)
37
-
38
35
/* TDX Module call error codes */
39
36
#define TDCALL_RETURN_CODE(a) ((a) >> 32)
40
37
#define TDCALL_INVALID_OPERAND 0xc0000100
···
197
200
*
198
201
* TDX 1.0 does not allow the guest to disable SEPT #VE on its own. The VMM
199
202
* controls if the guest will receive such #VE with TD attribute
200
-
* ATTR_SEPT_VE_DISABLE.
203
+
* TDX_ATTR_SEPT_VE_DISABLE.
201
204
*
202
205
* Newer TDX modules allow the guest to control if it wants to receive SEPT
203
206
* violation #VEs.
204
207
*
205
208
* Check if the feature is available and disable SEPT #VE if possible.
206
209
*
207
-
* If the TD is allowed to disable/enable SEPT #VEs, the ATTR_SEPT_VE_DISABLE
210
+
* If the TD is allowed to disable/enable SEPT #VEs, the TDX_ATTR_SEPT_VE_DISABLE
208
211
* attribute is no longer reliable. It reflects the initial state of the
209
212
* control for the TD, but it will not be updated if someone (e.g. bootloader)
210
213
* changes it before the kernel starts. Kernel must check TDCS_TD_CTLS bit to
···
213
216
static void disable_sept_ve(u64 td_attr)
214
217
{
215
218
const char *msg = "TD misconfiguration: SEPT #VE has to be disabled";
216
-
bool debug = td_attr & ATTR_DEBUG;
219
+
bool debug = td_attr & TDX_ATTR_DEBUG;
217
220
u64 config, controls;
218
221
219
222
/* Is this TD allowed to disable SEPT #VE */
220
223
tdg_vm_rd(TDCS_CONFIG_FLAGS, &config);
221
224
if (!(config & TDCS_CONFIG_FLEXIBLE_PENDING_VE)) {
222
225
/* No SEPT #VE controls for the guest: check the attribute */
223
-
if (td_attr & ATTR_SEPT_VE_DISABLE)
226
+
if (td_attr & TDX_ATTR_SEPT_VE_DISABLE)
224
227
return;
225
228
226
229
/* Relax SEPT_VE_DISABLE check for debug TD for backtraces */
···
271
274
tdg_vm_wr(TDCS_TD_CTLS, TD_CTLS_ENUM_TOPOLOGY, TD_CTLS_ENUM_TOPOLOGY);
272
275
}
273
276
277
+
static void reduce_unnecessary_ve(void)
278
+
{
279
+
u64 err = tdg_vm_wr(TDCS_TD_CTLS, TD_CTLS_REDUCE_VE, TD_CTLS_REDUCE_VE);
280
+
281
+
if (err == TDX_SUCCESS)
282
+
return;
283
+
284
+
/*
285
+
* Enabling REDUCE_VE includes ENUM_TOPOLOGY. Only try to
286
+
* enable ENUM_TOPOLOGY if REDUCE_VE was not successful.
287
+
*/
288
+
enable_cpu_topology_enumeration();
289
+
}
290
+
274
291
static void tdx_setup(u64 *cc_mask)
275
292
{
276
293
struct tdx_module_args args = {};
···
316
305
tdg_vm_wr(TDCS_NOTIFY_ENABLES, 0, -1ULL);
317
306
318
307
disable_sept_ve(td_attr);
319
-
enable_cpu_topology_enumeration();
308
+
309
+
reduce_unnecessary_ve();
320
310
}
321
311
322
312
/*
···
1037
1025
}
1038
1026
}
1039
1027
1028
+
static __init void tdx_announce(void)
1029
+
{
1030
+
struct tdx_module_args args = {};
1031
+
u64 controls;
1032
+
1033
+
pr_info("Guest detected\n");
1034
+
1035
+
tdcall(TDG_VP_INFO, &args);
1036
+
tdx_dump_attributes(args.rdx);
1037
+
1038
+
tdg_vm_rd(TDCS_TD_CTLS, &controls);
1039
+
tdx_dump_td_ctls(controls);
1040
+
}
1041
+
1040
1042
void __init tdx_early_init(void)
1041
1043
{
1042
1044
u64 cc_mask;
···
1120
1094
*/
1121
1095
x86_cpuinit.parallel_bringup = false;
1122
1096
1123
-
pr_info("Guest detected\n");
1097
+
tdx_announce();
1124
1098
}
+3
arch/x86/include/asm/tdx.h
+3
arch/x86/include/asm/tdx.h
+32
-65
arch/x86/virt/vmx/tdx/tdx.c
+32
-65
arch/x86/virt/vmx/tdx/tdx.c
···
270
270
return 0;
271
271
}
272
272
273
-
static int read_sys_metadata_field16(u64 field_id,
274
-
int offset,
275
-
struct tdx_tdmr_sysinfo *ts)
276
-
{
277
-
u16 *ts_member = ((void *)ts) + offset;
278
-
u64 tmp;
279
-
int ret;
273
+
#include "tdx_global_metadata.c"
280
274
281
-
if (WARN_ON_ONCE(MD_FIELD_ID_ELE_SIZE_CODE(field_id) !=
282
-
MD_FIELD_ID_ELE_SIZE_16BIT))
275
+
static int check_features(struct tdx_sys_info *sysinfo)
276
+
{
277
+
u64 tdx_features0 = sysinfo->features.tdx_features0;
278
+
279
+
if (!(tdx_features0 & TDX_FEATURES0_NO_RBP_MOD)) {
280
+
pr_err("frame pointer (RBP) clobber bug present, upgrade TDX module\n");
283
281
return -EINVAL;
284
-
285
-
ret = read_sys_metadata_field(field_id, &tmp);
286
-
if (ret)
287
-
return ret;
288
-
289
-
*ts_member = tmp;
290
-
291
-
return 0;
292
-
}
293
-
294
-
struct field_mapping {
295
-
u64 field_id;
296
-
int offset;
297
-
};
298
-
299
-
#define TD_SYSINFO_MAP(_field_id, _offset) \
300
-
{ .field_id = MD_FIELD_ID_##_field_id, \
301
-
.offset = offsetof(struct tdx_tdmr_sysinfo, _offset) }
302
-
303
-
/* Map TD_SYSINFO fields into 'struct tdx_tdmr_sysinfo': */
304
-
static const struct field_mapping fields[] = {
305
-
TD_SYSINFO_MAP(MAX_TDMRS, max_tdmrs),
306
-
TD_SYSINFO_MAP(MAX_RESERVED_PER_TDMR, max_reserved_per_tdmr),
307
-
TD_SYSINFO_MAP(PAMT_4K_ENTRY_SIZE, pamt_entry_size[TDX_PS_4K]),
308
-
TD_SYSINFO_MAP(PAMT_2M_ENTRY_SIZE, pamt_entry_size[TDX_PS_2M]),
309
-
TD_SYSINFO_MAP(PAMT_1G_ENTRY_SIZE, pamt_entry_size[TDX_PS_1G]),
310
-
};
311
-
312
-
static int get_tdx_tdmr_sysinfo(struct tdx_tdmr_sysinfo *tdmr_sysinfo)
313
-
{
314
-
int ret;
315
-
int i;
316
-
317
-
/* Populate 'tdmr_sysinfo' fields using the mapping structure above: */
318
-
for (i = 0; i < ARRAY_SIZE(fields); i++) {
319
-
ret = read_sys_metadata_field16(fields[i].field_id,
320
-
fields[i].offset,
321
-
tdmr_sysinfo);
322
-
if (ret)
323
-
return ret;
324
282
}
325
283
326
284
return 0;
···
300
342
}
301
343
302
344
static int alloc_tdmr_list(struct tdmr_info_list *tdmr_list,
303
-
struct tdx_tdmr_sysinfo *tdmr_sysinfo)
345
+
struct tdx_sys_info_tdmr *sysinfo_tdmr)
304
346
{
305
347
size_t tdmr_sz, tdmr_array_sz;
306
348
void *tdmr_array;
307
349
308
-
tdmr_sz = tdmr_size_single(tdmr_sysinfo->max_reserved_per_tdmr);
309
-
tdmr_array_sz = tdmr_sz * tdmr_sysinfo->max_tdmrs;
350
+
tdmr_sz = tdmr_size_single(sysinfo_tdmr->max_reserved_per_tdmr);
351
+
tdmr_array_sz = tdmr_sz * sysinfo_tdmr->max_tdmrs;
310
352
311
353
/*
312
354
* To keep things simple, allocate all TDMRs together.
···
325
367
* at a given index in the TDMR list.
326
368
*/
327
369
tdmr_list->tdmr_sz = tdmr_sz;
328
-
tdmr_list->max_tdmrs = tdmr_sysinfo->max_tdmrs;
370
+
tdmr_list->max_tdmrs = sysinfo_tdmr->max_tdmrs;
329
371
tdmr_list->nr_consumed_tdmrs = 0;
330
372
331
373
return 0;
···
879
921
/*
880
922
* Construct a list of TDMRs on the preallocated space in @tdmr_list
881
923
* to cover all TDX memory regions in @tmb_list based on the TDX module
882
-
* TDMR global information in @tdmr_sysinfo.
924
+
* TDMR global information in @sysinfo_tdmr.
883
925
*/
884
926
static int construct_tdmrs(struct list_head *tmb_list,
885
927
struct tdmr_info_list *tdmr_list,
886
-
struct tdx_tdmr_sysinfo *tdmr_sysinfo)
928
+
struct tdx_sys_info_tdmr *sysinfo_tdmr)
887
929
{
930
+
u16 pamt_entry_size[TDX_PS_NR] = {
931
+
sysinfo_tdmr->pamt_4k_entry_size,
932
+
sysinfo_tdmr->pamt_2m_entry_size,
933
+
sysinfo_tdmr->pamt_1g_entry_size,
934
+
};
888
935
int ret;
889
936
890
937
ret = fill_out_tdmrs(tmb_list, tdmr_list);
891
938
if (ret)
892
939
return ret;
893
940
894
-
ret = tdmrs_set_up_pamt_all(tdmr_list, tmb_list,
895
-
tdmr_sysinfo->pamt_entry_size);
941
+
ret = tdmrs_set_up_pamt_all(tdmr_list, tmb_list, pamt_entry_size);
896
942
if (ret)
897
943
return ret;
898
944
899
945
ret = tdmrs_populate_rsvd_areas_all(tdmr_list, tmb_list,
900
-
tdmr_sysinfo->max_reserved_per_tdmr);
946
+
sysinfo_tdmr->max_reserved_per_tdmr);
901
947
if (ret)
902
948
tdmrs_free_pamt_all(tdmr_list);
903
949
···
1060
1098
1061
1099
static int init_tdx_module(void)
1062
1100
{
1063
-
struct tdx_tdmr_sysinfo tdmr_sysinfo;
1101
+
struct tdx_sys_info sysinfo;
1064
1102
int ret;
1103
+
1104
+
ret = get_tdx_sys_info(&sysinfo);
1105
+
if (ret)
1106
+
return ret;
1107
+
1108
+
/* Check whether the kernel can support this module */
1109
+
ret = check_features(&sysinfo);
1110
+
if (ret)
1111
+
return ret;
1065
1112
1066
1113
/*
1067
1114
* To keep things simple, assume that all TDX-protected memory
···
1088
1117
if (ret)
1089
1118
goto out_put_tdxmem;
1090
1119
1091
-
ret = get_tdx_tdmr_sysinfo(&tdmr_sysinfo);
1092
-
if (ret)
1093
-
goto err_free_tdxmem;
1094
-
1095
1120
/* Allocate enough space for constructing TDMRs */
1096
-
ret = alloc_tdmr_list(&tdx_tdmr_list, &tdmr_sysinfo);
1121
+
ret = alloc_tdmr_list(&tdx_tdmr_list, &sysinfo.tdmr);
1097
1122
if (ret)
1098
1123
goto err_free_tdxmem;
1099
1124
1100
1125
/* Cover all TDX-usable memory regions in TDMRs */
1101
-
ret = construct_tdmrs(&tdx_memlist, &tdx_tdmr_list, &tdmr_sysinfo);
1126
+
ret = construct_tdmrs(&tdx_memlist, &tdx_tdmr_list, &sysinfo.tdmr);
1102
1127
if (ret)
1103
1128
goto err_free_tdmrs;
1104
1129
+4
-36
arch/x86/virt/vmx/tdx/tdx.h
+4
-36
arch/x86/virt/vmx/tdx/tdx.h
···
3
3
#define _X86_VIRT_TDX_H
4
4
5
5
#include <linux/bits.h>
6
+
#include "tdx_global_metadata.h"
6
7
7
8
/*
8
9
* This file contains both macros and data structures defined by the TDX
···
26
25
/* TDX page types */
27
26
#define PT_NDA 0x0
28
27
#define PT_RSVD 0x1
29
-
30
-
/*
31
-
* Global scope metadata field ID.
32
-
*
33
-
* See Table "Global Scope Metadata", TDX module 1.5 ABI spec.
34
-
*/
35
-
#define MD_FIELD_ID_MAX_TDMRS 0x9100000100000008ULL
36
-
#define MD_FIELD_ID_MAX_RESERVED_PER_TDMR 0x9100000100000009ULL
37
-
#define MD_FIELD_ID_PAMT_4K_ENTRY_SIZE 0x9100000100000010ULL
38
-
#define MD_FIELD_ID_PAMT_2M_ENTRY_SIZE 0x9100000100000011ULL
39
-
#define MD_FIELD_ID_PAMT_1G_ENTRY_SIZE 0x9100000100000012ULL
40
-
41
-
/*
42
-
* Sub-field definition of metadata field ID.
43
-
*
44
-
* See Table "MD_FIELD_ID (Metadata Field Identifier / Sequence Header)
45
-
* Definition", TDX module 1.5 ABI spec.
46
-
*
47
-
* - Bit 33:32: ELEMENT_SIZE_CODE -- size of a single element of metadata
48
-
*
49
-
* 0: 8 bits
50
-
* 1: 16 bits
51
-
* 2: 32 bits
52
-
* 3: 64 bits
53
-
*/
54
-
#define MD_FIELD_ID_ELE_SIZE_CODE(_field_id) \
55
-
(((_field_id) & GENMASK_ULL(33, 32)) >> 32)
56
-
57
-
#define MD_FIELD_ID_ELE_SIZE_16BIT 1
58
28
59
29
struct tdmr_reserved_area {
60
30
u64 offset;
···
52
80
DECLARE_FLEX_ARRAY(struct tdmr_reserved_area, reserved_areas);
53
81
} __packed __aligned(TDMR_INFO_ALIGNMENT);
54
82
83
+
/* Bit definitions of TDX_FEATURES0 metadata field */
84
+
#define TDX_FEATURES0_NO_RBP_MOD BIT(18)
85
+
55
86
/*
56
87
* Do not put any hardware-defined TDX structure representations below
57
88
* this comment!
···
72
97
unsigned long start_pfn;
73
98
unsigned long end_pfn;
74
99
int nid;
75
-
};
76
-
77
-
/* "TDMR info" part of "Global Scope Metadata" for constructing TDMRs */
78
-
struct tdx_tdmr_sysinfo {
79
-
u16 max_tdmrs;
80
-
u16 max_reserved_per_tdmr;
81
-
u16 pamt_entry_size[TDX_PS_NR];
82
100
};
83
101
84
102
/* Warn if kernel has less than TDMR_NR_WARN TDMRs after allocation */
+48
arch/x86/virt/vmx/tdx/tdx_global_metadata.c
+48
arch/x86/virt/vmx/tdx/tdx_global_metadata.c
···
1
+
// SPDX-License-Identifier: GPL-2.0
2
+
/*
3
+
* Automatically generated functions to read TDX global metadata.
4
+
*
5
+
* This file doesn't compile on its own as it lacks of inclusion
6
+
* of SEAMCALL wrapper primitive which reads global metadata.
7
+
* Include this file to other C file instead.
8
+
*/
9
+
10
+
static int get_tdx_sys_info_features(struct tdx_sys_info_features *sysinfo_features)
11
+
{
12
+
int ret = 0;
13
+
u64 val;
14
+
15
+
if (!ret && !(ret = read_sys_metadata_field(0x0A00000300000008, &val)))
16
+
sysinfo_features->tdx_features0 = val;
17
+
18
+
return ret;
19
+
}
20
+
21
+
static int get_tdx_sys_info_tdmr(struct tdx_sys_info_tdmr *sysinfo_tdmr)
22
+
{
23
+
int ret = 0;
24
+
u64 val;
25
+
26
+
if (!ret && !(ret = read_sys_metadata_field(0x9100000100000008, &val)))
27
+
sysinfo_tdmr->max_tdmrs = val;
28
+
if (!ret && !(ret = read_sys_metadata_field(0x9100000100000009, &val)))
29
+
sysinfo_tdmr->max_reserved_per_tdmr = val;
30
+
if (!ret && !(ret = read_sys_metadata_field(0x9100000100000010, &val)))
31
+
sysinfo_tdmr->pamt_4k_entry_size = val;
32
+
if (!ret && !(ret = read_sys_metadata_field(0x9100000100000011, &val)))
33
+
sysinfo_tdmr->pamt_2m_entry_size = val;
34
+
if (!ret && !(ret = read_sys_metadata_field(0x9100000100000012, &val)))
35
+
sysinfo_tdmr->pamt_1g_entry_size = val;
36
+
37
+
return ret;
38
+
}
39
+
40
+
static int get_tdx_sys_info(struct tdx_sys_info *sysinfo)
41
+
{
42
+
int ret = 0;
43
+
44
+
ret = ret ?: get_tdx_sys_info_features(&sysinfo->features);
45
+
ret = ret ?: get_tdx_sys_info_tdmr(&sysinfo->tdmr);
46
+
47
+
return ret;
48
+
}
+25
arch/x86/virt/vmx/tdx/tdx_global_metadata.h
+25
arch/x86/virt/vmx/tdx/tdx_global_metadata.h
···
1
+
/* SPDX-License-Identifier: GPL-2.0 */
2
+
/* Automatically generated TDX global metadata structures. */
3
+
#ifndef _X86_VIRT_TDX_AUTO_GENERATED_TDX_GLOBAL_METADATA_H
4
+
#define _X86_VIRT_TDX_AUTO_GENERATED_TDX_GLOBAL_METADATA_H
5
+
6
+
#include <linux/types.h>
7
+
8
+
struct tdx_sys_info_features {
9
+
u64 tdx_features0;
10
+
};
11
+
12
+
struct tdx_sys_info_tdmr {
13
+
u16 max_tdmrs;
14
+
u16 max_reserved_per_tdmr;
15
+
u16 pamt_4k_entry_size;
16
+
u16 pamt_2m_entry_size;
17
+
u16 pamt_1g_entry_size;
18
+
};
19
+
20
+
struct tdx_sys_info {
21
+
struct tdx_sys_info_features features;
22
+
struct tdx_sys_info_tdmr tdmr;
23
+
};
24
+
25
+
#endif