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v5.4
  1/* Declare dependencies between CPUIDs */
  2#include <linux/kernel.h>
  3#include <linux/init.h>
  4#include <linux/module.h>
  5#include <asm/cpufeature.h>
  6
  7struct cpuid_dep {
  8	unsigned int	feature;
  9	unsigned int	depends;
 10};
 11
 12/*
 13 * Table of CPUID features that depend on others.
 14 *
 15 * This only includes dependencies that can be usefully disabled, not
 16 * features part of the base set (like FPU).
 17 *
 18 * Note this all is not __init / __initdata because it can be
 19 * called from cpu hotplug. It shouldn't do anything in this case,
 20 * but it's difficult to tell that to the init reference checker.
 21 */
 22static const struct cpuid_dep cpuid_deps[] = {
 23	{ X86_FEATURE_FXSR,			X86_FEATURE_FPU	      },
 24	{ X86_FEATURE_XSAVEOPT,			X86_FEATURE_XSAVE     },
 25	{ X86_FEATURE_XSAVEC,			X86_FEATURE_XSAVE     },
 26	{ X86_FEATURE_XSAVES,			X86_FEATURE_XSAVE     },
 27	{ X86_FEATURE_AVX,			X86_FEATURE_XSAVE     },
 28	{ X86_FEATURE_PKU,			X86_FEATURE_XSAVE     },
 29	{ X86_FEATURE_MPX,			X86_FEATURE_XSAVE     },
 30	{ X86_FEATURE_XGETBV1,			X86_FEATURE_XSAVE     },
 31	{ X86_FEATURE_CMOV,			X86_FEATURE_FXSR      },
 32	{ X86_FEATURE_MMX,			X86_FEATURE_FXSR      },
 33	{ X86_FEATURE_MMXEXT,			X86_FEATURE_MMX       },
 34	{ X86_FEATURE_FXSR_OPT,			X86_FEATURE_FXSR      },
 35	{ X86_FEATURE_XSAVE,			X86_FEATURE_FXSR      },
 36	{ X86_FEATURE_XMM,			X86_FEATURE_FXSR      },
 37	{ X86_FEATURE_XMM2,			X86_FEATURE_XMM       },
 38	{ X86_FEATURE_XMM3,			X86_FEATURE_XMM2      },
 39	{ X86_FEATURE_XMM4_1,			X86_FEATURE_XMM2      },
 40	{ X86_FEATURE_XMM4_2,			X86_FEATURE_XMM2      },
 41	{ X86_FEATURE_XMM3,			X86_FEATURE_XMM2      },
 42	{ X86_FEATURE_PCLMULQDQ,		X86_FEATURE_XMM2      },
 43	{ X86_FEATURE_SSSE3,			X86_FEATURE_XMM2,     },
 44	{ X86_FEATURE_F16C,			X86_FEATURE_XMM2,     },
 45	{ X86_FEATURE_AES,			X86_FEATURE_XMM2      },
 46	{ X86_FEATURE_SHA_NI,			X86_FEATURE_XMM2      },
 47	{ X86_FEATURE_FMA,			X86_FEATURE_AVX       },
 48	{ X86_FEATURE_AVX2,			X86_FEATURE_AVX,      },
 49	{ X86_FEATURE_AVX512F,			X86_FEATURE_AVX,      },
 50	{ X86_FEATURE_AVX512IFMA,		X86_FEATURE_AVX512F   },
 51	{ X86_FEATURE_AVX512PF,			X86_FEATURE_AVX512F   },
 52	{ X86_FEATURE_AVX512ER,			X86_FEATURE_AVX512F   },
 53	{ X86_FEATURE_AVX512CD,			X86_FEATURE_AVX512F   },
 54	{ X86_FEATURE_AVX512DQ,			X86_FEATURE_AVX512F   },
 55	{ X86_FEATURE_AVX512BW,			X86_FEATURE_AVX512F   },
 56	{ X86_FEATURE_AVX512VL,			X86_FEATURE_AVX512F   },
 57	{ X86_FEATURE_AVX512VBMI,		X86_FEATURE_AVX512F   },
 58	{ X86_FEATURE_AVX512_VBMI2,		X86_FEATURE_AVX512VL  },
 59	{ X86_FEATURE_GFNI,			X86_FEATURE_AVX512VL  },
 60	{ X86_FEATURE_VAES,			X86_FEATURE_AVX512VL  },
 61	{ X86_FEATURE_VPCLMULQDQ,		X86_FEATURE_AVX512VL  },
 62	{ X86_FEATURE_AVX512_VNNI,		X86_FEATURE_AVX512VL  },
 63	{ X86_FEATURE_AVX512_BITALG,		X86_FEATURE_AVX512VL  },
 64	{ X86_FEATURE_AVX512_4VNNIW,		X86_FEATURE_AVX512F   },
 65	{ X86_FEATURE_AVX512_4FMAPS,		X86_FEATURE_AVX512F   },
 66	{ X86_FEATURE_AVX512_VPOPCNTDQ,		X86_FEATURE_AVX512F   },
 67	{ X86_FEATURE_AVX512_VP2INTERSECT,	X86_FEATURE_AVX512VL  },
 68	{ X86_FEATURE_CQM_OCCUP_LLC,		X86_FEATURE_CQM_LLC   },
 69	{ X86_FEATURE_CQM_MBM_TOTAL,		X86_FEATURE_CQM_LLC   },
 70	{ X86_FEATURE_CQM_MBM_LOCAL,		X86_FEATURE_CQM_LLC   },
 71	{ X86_FEATURE_AVX512_BF16,		X86_FEATURE_AVX512VL  },
 
 
 
 
 
 
 
 
 
 
 72	{}
 73};
 74
 75static inline void clear_feature(struct cpuinfo_x86 *c, unsigned int feature)
 76{
 77	/*
 78	 * Note: This could use the non atomic __*_bit() variants, but the
 79	 * rest of the cpufeature code uses atomics as well, so keep it for
 80	 * consistency. Cleanup all of it separately.
 81	 */
 82	if (!c) {
 83		clear_cpu_cap(&boot_cpu_data, feature);
 84		set_bit(feature, (unsigned long *)cpu_caps_cleared);
 85	} else {
 86		clear_bit(feature, (unsigned long *)c->x86_capability);
 87	}
 88}
 89
 90/* Take the capabilities and the BUG bits into account */
 91#define MAX_FEATURE_BITS ((NCAPINTS + NBUGINTS) * sizeof(u32) * 8)
 92
 93static void do_clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
 94{
 95	DECLARE_BITMAP(disable, MAX_FEATURE_BITS);
 96	const struct cpuid_dep *d;
 97	bool changed;
 98
 99	if (WARN_ON(feature >= MAX_FEATURE_BITS))
100		return;
101
102	clear_feature(c, feature);
103
104	/* Collect all features to disable, handling dependencies */
105	memset(disable, 0, sizeof(disable));
106	__set_bit(feature, disable);
107
108	/* Loop until we get a stable state. */
109	do {
110		changed = false;
111		for (d = cpuid_deps; d->feature; d++) {
112			if (!test_bit(d->depends, disable))
113				continue;
114			if (__test_and_set_bit(d->feature, disable))
115				continue;
116
117			changed = true;
118			clear_feature(c, d->feature);
119		}
120	} while (changed);
121}
122
123void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
124{
125	do_clear_cpu_cap(c, feature);
126}
127
128void setup_clear_cpu_cap(unsigned int feature)
129{
130	do_clear_cpu_cap(NULL, feature);
131}
v6.2
  1/* Declare dependencies between CPUIDs */
  2#include <linux/kernel.h>
  3#include <linux/init.h>
  4#include <linux/module.h>
  5#include <asm/cpufeature.h>
  6
  7struct cpuid_dep {
  8	unsigned int	feature;
  9	unsigned int	depends;
 10};
 11
 12/*
 13 * Table of CPUID features that depend on others.
 14 *
 15 * This only includes dependencies that can be usefully disabled, not
 16 * features part of the base set (like FPU).
 17 *
 18 * Note this all is not __init / __initdata because it can be
 19 * called from cpu hotplug. It shouldn't do anything in this case,
 20 * but it's difficult to tell that to the init reference checker.
 21 */
 22static const struct cpuid_dep cpuid_deps[] = {
 23	{ X86_FEATURE_FXSR,			X86_FEATURE_FPU	      },
 24	{ X86_FEATURE_XSAVEOPT,			X86_FEATURE_XSAVE     },
 25	{ X86_FEATURE_XSAVEC,			X86_FEATURE_XSAVE     },
 26	{ X86_FEATURE_XSAVES,			X86_FEATURE_XSAVE     },
 27	{ X86_FEATURE_AVX,			X86_FEATURE_XSAVE     },
 28	{ X86_FEATURE_PKU,			X86_FEATURE_XSAVE     },
 29	{ X86_FEATURE_MPX,			X86_FEATURE_XSAVE     },
 30	{ X86_FEATURE_XGETBV1,			X86_FEATURE_XSAVE     },
 31	{ X86_FEATURE_CMOV,			X86_FEATURE_FXSR      },
 32	{ X86_FEATURE_MMX,			X86_FEATURE_FXSR      },
 33	{ X86_FEATURE_MMXEXT,			X86_FEATURE_MMX       },
 34	{ X86_FEATURE_FXSR_OPT,			X86_FEATURE_FXSR      },
 35	{ X86_FEATURE_XSAVE,			X86_FEATURE_FXSR      },
 36	{ X86_FEATURE_XMM,			X86_FEATURE_FXSR      },
 37	{ X86_FEATURE_XMM2,			X86_FEATURE_XMM       },
 38	{ X86_FEATURE_XMM3,			X86_FEATURE_XMM2      },
 39	{ X86_FEATURE_XMM4_1,			X86_FEATURE_XMM2      },
 40	{ X86_FEATURE_XMM4_2,			X86_FEATURE_XMM2      },
 41	{ X86_FEATURE_XMM3,			X86_FEATURE_XMM2      },
 42	{ X86_FEATURE_PCLMULQDQ,		X86_FEATURE_XMM2      },
 43	{ X86_FEATURE_SSSE3,			X86_FEATURE_XMM2,     },
 44	{ X86_FEATURE_F16C,			X86_FEATURE_XMM2,     },
 45	{ X86_FEATURE_AES,			X86_FEATURE_XMM2      },
 46	{ X86_FEATURE_SHA_NI,			X86_FEATURE_XMM2      },
 47	{ X86_FEATURE_FMA,			X86_FEATURE_AVX       },
 48	{ X86_FEATURE_AVX2,			X86_FEATURE_AVX,      },
 49	{ X86_FEATURE_AVX512F,			X86_FEATURE_AVX,      },
 50	{ X86_FEATURE_AVX512IFMA,		X86_FEATURE_AVX512F   },
 51	{ X86_FEATURE_AVX512PF,			X86_FEATURE_AVX512F   },
 52	{ X86_FEATURE_AVX512ER,			X86_FEATURE_AVX512F   },
 53	{ X86_FEATURE_AVX512CD,			X86_FEATURE_AVX512F   },
 54	{ X86_FEATURE_AVX512DQ,			X86_FEATURE_AVX512F   },
 55	{ X86_FEATURE_AVX512BW,			X86_FEATURE_AVX512F   },
 56	{ X86_FEATURE_AVX512VL,			X86_FEATURE_AVX512F   },
 57	{ X86_FEATURE_AVX512VBMI,		X86_FEATURE_AVX512F   },
 58	{ X86_FEATURE_AVX512_VBMI2,		X86_FEATURE_AVX512VL  },
 59	{ X86_FEATURE_GFNI,			X86_FEATURE_AVX512VL  },
 60	{ X86_FEATURE_VAES,			X86_FEATURE_AVX512VL  },
 61	{ X86_FEATURE_VPCLMULQDQ,		X86_FEATURE_AVX512VL  },
 62	{ X86_FEATURE_AVX512_VNNI,		X86_FEATURE_AVX512VL  },
 63	{ X86_FEATURE_AVX512_BITALG,		X86_FEATURE_AVX512VL  },
 64	{ X86_FEATURE_AVX512_4VNNIW,		X86_FEATURE_AVX512F   },
 65	{ X86_FEATURE_AVX512_4FMAPS,		X86_FEATURE_AVX512F   },
 66	{ X86_FEATURE_AVX512_VPOPCNTDQ,		X86_FEATURE_AVX512F   },
 67	{ X86_FEATURE_AVX512_VP2INTERSECT,	X86_FEATURE_AVX512VL  },
 68	{ X86_FEATURE_CQM_OCCUP_LLC,		X86_FEATURE_CQM_LLC   },
 69	{ X86_FEATURE_CQM_MBM_TOTAL,		X86_FEATURE_CQM_LLC   },
 70	{ X86_FEATURE_CQM_MBM_LOCAL,		X86_FEATURE_CQM_LLC   },
 71	{ X86_FEATURE_AVX512_BF16,		X86_FEATURE_AVX512VL  },
 72	{ X86_FEATURE_AVX512_FP16,		X86_FEATURE_AVX512BW  },
 73	{ X86_FEATURE_ENQCMD,			X86_FEATURE_XSAVES    },
 74	{ X86_FEATURE_PER_THREAD_MBA,		X86_FEATURE_MBA       },
 75	{ X86_FEATURE_SGX_LC,			X86_FEATURE_SGX	      },
 76	{ X86_FEATURE_SGX1,			X86_FEATURE_SGX       },
 77	{ X86_FEATURE_SGX2,			X86_FEATURE_SGX1      },
 78	{ X86_FEATURE_SGX_EDECCSSA,		X86_FEATURE_SGX1      },
 79	{ X86_FEATURE_XFD,			X86_FEATURE_XSAVES    },
 80	{ X86_FEATURE_XFD,			X86_FEATURE_XGETBV1   },
 81	{ X86_FEATURE_AMX_TILE,			X86_FEATURE_XFD       },
 82	{}
 83};
 84
 85static inline void clear_feature(struct cpuinfo_x86 *c, unsigned int feature)
 86{
 87	/*
 88	 * Note: This could use the non atomic __*_bit() variants, but the
 89	 * rest of the cpufeature code uses atomics as well, so keep it for
 90	 * consistency. Cleanup all of it separately.
 91	 */
 92	if (!c) {
 93		clear_cpu_cap(&boot_cpu_data, feature);
 94		set_bit(feature, (unsigned long *)cpu_caps_cleared);
 95	} else {
 96		clear_bit(feature, (unsigned long *)c->x86_capability);
 97	}
 98}
 99
100/* Take the capabilities and the BUG bits into account */
101#define MAX_FEATURE_BITS ((NCAPINTS + NBUGINTS) * sizeof(u32) * 8)
102
103static void do_clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
104{
105	DECLARE_BITMAP(disable, MAX_FEATURE_BITS);
106	const struct cpuid_dep *d;
107	bool changed;
108
109	if (WARN_ON(feature >= MAX_FEATURE_BITS))
110		return;
111
112	clear_feature(c, feature);
113
114	/* Collect all features to disable, handling dependencies */
115	memset(disable, 0, sizeof(disable));
116	__set_bit(feature, disable);
117
118	/* Loop until we get a stable state. */
119	do {
120		changed = false;
121		for (d = cpuid_deps; d->feature; d++) {
122			if (!test_bit(d->depends, disable))
123				continue;
124			if (__test_and_set_bit(d->feature, disable))
125				continue;
126
127			changed = true;
128			clear_feature(c, d->feature);
129		}
130	} while (changed);
131}
132
133void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
134{
135	do_clear_cpu_cap(c, feature);
136}
137
138void setup_clear_cpu_cap(unsigned int feature)
139{
140	do_clear_cpu_cap(NULL, feature);
141}