1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
/* Declare dependencies between CPUIDs */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <asm/cpufeature.h>
struct cpuid_dep {
unsigned int feature;
unsigned int depends;
};
/*
* Table of CPUID features that depend on others.
*
* This only includes dependencies that can be usefully disabled, not
* features part of the base set (like FPU).
*
* Note this all is not __init / __initdata because it can be
* called from cpu hotplug. It shouldn't do anything in this case,
* but it's difficult to tell that to the init reference checker.
*/
static const struct cpuid_dep cpuid_deps[] = {
{ X86_FEATURE_FXSR, X86_FEATURE_FPU },
{ X86_FEATURE_XSAVEOPT, X86_FEATURE_XSAVE },
{ X86_FEATURE_XSAVEC, X86_FEATURE_XSAVE },
{ X86_FEATURE_XSAVES, X86_FEATURE_XSAVE },
{ X86_FEATURE_AVX, X86_FEATURE_XSAVE },
{ X86_FEATURE_PKU, X86_FEATURE_XSAVE },
{ X86_FEATURE_MPX, X86_FEATURE_XSAVE },
{ X86_FEATURE_XGETBV1, X86_FEATURE_XSAVE },
{ X86_FEATURE_CMOV, X86_FEATURE_FXSR },
{ X86_FEATURE_MMX, X86_FEATURE_FXSR },
{ X86_FEATURE_MMXEXT, X86_FEATURE_MMX },
{ X86_FEATURE_FXSR_OPT, X86_FEATURE_FXSR },
{ X86_FEATURE_XSAVE, X86_FEATURE_FXSR },
{ X86_FEATURE_XMM, X86_FEATURE_FXSR },
{ X86_FEATURE_XMM2, X86_FEATURE_XMM },
{ X86_FEATURE_XMM3, X86_FEATURE_XMM2 },
{ X86_FEATURE_XMM4_1, X86_FEATURE_XMM2 },
{ X86_FEATURE_XMM4_2, X86_FEATURE_XMM2 },
{ X86_FEATURE_XMM3, X86_FEATURE_XMM2 },
{ X86_FEATURE_PCLMULQDQ, X86_FEATURE_XMM2 },
{ X86_FEATURE_SSSE3, X86_FEATURE_XMM2, },
{ X86_FEATURE_F16C, X86_FEATURE_XMM2, },
{ X86_FEATURE_AES, X86_FEATURE_XMM2 },
{ X86_FEATURE_SHA_NI, X86_FEATURE_XMM2 },
{ X86_FEATURE_GFNI, X86_FEATURE_XMM2 },
{ X86_FEATURE_FMA, X86_FEATURE_AVX },
{ X86_FEATURE_VAES, X86_FEATURE_AVX },
{ X86_FEATURE_VPCLMULQDQ, X86_FEATURE_AVX },
{ X86_FEATURE_AVX2, X86_FEATURE_AVX, },
{ X86_FEATURE_AVX512F, X86_FEATURE_AVX, },
{ X86_FEATURE_AVX512IFMA, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512PF, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512ER, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512CD, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512DQ, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512BW, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512VL, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512VBMI, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512_VBMI2, X86_FEATURE_AVX512VL },
{ X86_FEATURE_AVX512_VNNI, X86_FEATURE_AVX512VL },
{ X86_FEATURE_AVX512_BITALG, X86_FEATURE_AVX512VL },
{ X86_FEATURE_AVX512_4VNNIW, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512_4FMAPS, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512_VPOPCNTDQ, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512_VP2INTERSECT, X86_FEATURE_AVX512VL },
{ X86_FEATURE_CQM_OCCUP_LLC, X86_FEATURE_CQM_LLC },
{ X86_FEATURE_CQM_MBM_TOTAL, X86_FEATURE_CQM_LLC },
{ X86_FEATURE_CQM_MBM_LOCAL, X86_FEATURE_CQM_LLC },
{ X86_FEATURE_AVX512_BF16, X86_FEATURE_AVX512VL },
{ X86_FEATURE_ENQCMD, X86_FEATURE_XSAVES },
{ X86_FEATURE_PER_THREAD_MBA, X86_FEATURE_MBA },
{}
};
static inline void clear_feature(struct cpuinfo_x86 *c, unsigned int feature)
{
/*
* Note: This could use the non atomic __*_bit() variants, but the
* rest of the cpufeature code uses atomics as well, so keep it for
* consistency. Cleanup all of it separately.
*/
if (!c) {
clear_cpu_cap(&boot_cpu_data, feature);
set_bit(feature, (unsigned long *)cpu_caps_cleared);
} else {
clear_bit(feature, (unsigned long *)c->x86_capability);
}
}
/* Take the capabilities and the BUG bits into account */
#define MAX_FEATURE_BITS ((NCAPINTS + NBUGINTS) * sizeof(u32) * 8)
static void do_clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
{
DECLARE_BITMAP(disable, MAX_FEATURE_BITS);
const struct cpuid_dep *d;
bool changed;
if (WARN_ON(feature >= MAX_FEATURE_BITS))
return;
clear_feature(c, feature);
/* Collect all features to disable, handling dependencies */
memset(disable, 0, sizeof(disable));
__set_bit(feature, disable);
/* Loop until we get a stable state. */
do {
changed = false;
for (d = cpuid_deps; d->feature; d++) {
if (!test_bit(d->depends, disable))
continue;
if (__test_and_set_bit(d->feature, disable))
continue;
changed = true;
clear_feature(c, d->feature);
}
} while (changed);
}
void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
{
do_clear_cpu_cap(c, feature);
}
void setup_clear_cpu_cap(unsigned int feature)
{
do_clear_cpu_cap(NULL, feature);
}
|
