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v4.17
  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_XSAVEOPT,		X86_FEATURE_XSAVE     },
 24	{ X86_FEATURE_XSAVEC,		X86_FEATURE_XSAVE     },
 25	{ X86_FEATURE_XSAVES,		X86_FEATURE_XSAVE     },
 26	{ X86_FEATURE_AVX,		X86_FEATURE_XSAVE     },
 27	{ X86_FEATURE_PKU,		X86_FEATURE_XSAVE     },
 28	{ X86_FEATURE_MPX,		X86_FEATURE_XSAVE     },
 29	{ X86_FEATURE_XGETBV1,		X86_FEATURE_XSAVE     },
 30	{ X86_FEATURE_FXSR_OPT,		X86_FEATURE_FXSR      },
 31	{ X86_FEATURE_XMM,		X86_FEATURE_FXSR      },
 32	{ X86_FEATURE_XMM2,		X86_FEATURE_XMM       },
 33	{ X86_FEATURE_XMM3,		X86_FEATURE_XMM2      },
 34	{ X86_FEATURE_XMM4_1,		X86_FEATURE_XMM2      },
 35	{ X86_FEATURE_XMM4_2,		X86_FEATURE_XMM2      },
 36	{ X86_FEATURE_XMM3,		X86_FEATURE_XMM2      },
 37	{ X86_FEATURE_PCLMULQDQ,	X86_FEATURE_XMM2      },
 38	{ X86_FEATURE_SSSE3,		X86_FEATURE_XMM2,     },
 39	{ X86_FEATURE_F16C,		X86_FEATURE_XMM2,     },
 40	{ X86_FEATURE_AES,		X86_FEATURE_XMM2      },
 41	{ X86_FEATURE_SHA_NI,		X86_FEATURE_XMM2      },
 42	{ X86_FEATURE_FMA,		X86_FEATURE_AVX       },
 43	{ X86_FEATURE_AVX2,		X86_FEATURE_AVX,      },
 44	{ X86_FEATURE_AVX512F,		X86_FEATURE_AVX,      },
 45	{ X86_FEATURE_AVX512IFMA,	X86_FEATURE_AVX512F   },
 46	{ X86_FEATURE_AVX512PF,		X86_FEATURE_AVX512F   },
 47	{ X86_FEATURE_AVX512ER,		X86_FEATURE_AVX512F   },
 48	{ X86_FEATURE_AVX512CD,		X86_FEATURE_AVX512F   },
 49	{ X86_FEATURE_AVX512DQ,		X86_FEATURE_AVX512F   },
 50	{ X86_FEATURE_AVX512BW,		X86_FEATURE_AVX512F   },
 51	{ X86_FEATURE_AVX512VL,		X86_FEATURE_AVX512F   },
 52	{ X86_FEATURE_AVX512VBMI,	X86_FEATURE_AVX512F   },
 53	{ X86_FEATURE_AVX512_VBMI2,	X86_FEATURE_AVX512VL  },
 54	{ X86_FEATURE_GFNI,		X86_FEATURE_AVX512VL  },
 55	{ X86_FEATURE_VAES,		X86_FEATURE_AVX512VL  },
 56	{ X86_FEATURE_VPCLMULQDQ,	X86_FEATURE_AVX512VL  },
 57	{ X86_FEATURE_AVX512_VNNI,	X86_FEATURE_AVX512VL  },
 58	{ X86_FEATURE_AVX512_BITALG,	X86_FEATURE_AVX512VL  },
 59	{ X86_FEATURE_AVX512_4VNNIW,	X86_FEATURE_AVX512F   },
 60	{ X86_FEATURE_AVX512_4FMAPS,	X86_FEATURE_AVX512F   },
 61	{ X86_FEATURE_AVX512_VPOPCNTDQ, X86_FEATURE_AVX512F   },
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 62	{}
 63};
 64
 65static inline void clear_feature(struct cpuinfo_x86 *c, unsigned int feature)
 66{
 67	/*
 68	 * Note: This could use the non atomic __*_bit() variants, but the
 69	 * rest of the cpufeature code uses atomics as well, so keep it for
 70	 * consistency. Cleanup all of it separately.
 71	 */
 72	if (!c) {
 73		clear_cpu_cap(&boot_cpu_data, feature);
 74		set_bit(feature, (unsigned long *)cpu_caps_cleared);
 75	} else {
 76		clear_bit(feature, (unsigned long *)c->x86_capability);
 77	}
 78}
 79
 80/* Take the capabilities and the BUG bits into account */
 81#define MAX_FEATURE_BITS ((NCAPINTS + NBUGINTS) * sizeof(u32) * 8)
 82
 83static void do_clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
 84{
 85	DECLARE_BITMAP(disable, MAX_FEATURE_BITS);
 86	const struct cpuid_dep *d;
 87	bool changed;
 88
 89	if (WARN_ON(feature >= MAX_FEATURE_BITS))
 90		return;
 91
 92	clear_feature(c, feature);
 93
 94	/* Collect all features to disable, handling dependencies */
 95	memset(disable, 0, sizeof(disable));
 96	__set_bit(feature, disable);
 97
 98	/* Loop until we get a stable state. */
 99	do {
100		changed = false;
101		for (d = cpuid_deps; d->feature; d++) {
102			if (!test_bit(d->depends, disable))
103				continue;
104			if (__test_and_set_bit(d->feature, disable))
105				continue;
106
107			changed = true;
108			clear_feature(c, d->feature);
109		}
110	} while (changed);
111}
112
113void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
114{
115	do_clear_cpu_cap(c, feature);
116}
117
118void setup_clear_cpu_cap(unsigned int feature)
119{
120	do_clear_cpu_cap(NULL, feature);
121}
v6.8
  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_BMEC,			X86_FEATURE_CQM_MBM_TOTAL   },
 72	{ X86_FEATURE_BMEC,			X86_FEATURE_CQM_MBM_LOCAL   },
 73	{ X86_FEATURE_AVX512_BF16,		X86_FEATURE_AVX512VL  },
 74	{ X86_FEATURE_AVX512_FP16,		X86_FEATURE_AVX512BW  },
 75	{ X86_FEATURE_ENQCMD,			X86_FEATURE_XSAVES    },
 76	{ X86_FEATURE_PER_THREAD_MBA,		X86_FEATURE_MBA       },
 77	{ X86_FEATURE_SGX_LC,			X86_FEATURE_SGX	      },
 78	{ X86_FEATURE_SGX1,			X86_FEATURE_SGX       },
 79	{ X86_FEATURE_SGX2,			X86_FEATURE_SGX1      },
 80	{ X86_FEATURE_SGX_EDECCSSA,		X86_FEATURE_SGX1      },
 81	{ X86_FEATURE_XFD,			X86_FEATURE_XSAVES    },
 82	{ X86_FEATURE_XFD,			X86_FEATURE_XGETBV1   },
 83	{ X86_FEATURE_AMX_TILE,			X86_FEATURE_XFD       },
 84	{ X86_FEATURE_SHSTK,			X86_FEATURE_XSAVES    },
 85	{}
 86};
 87
 88static inline void clear_feature(struct cpuinfo_x86 *c, unsigned int feature)
 89{
 90	/*
 91	 * Note: This could use the non atomic __*_bit() variants, but the
 92	 * rest of the cpufeature code uses atomics as well, so keep it for
 93	 * consistency. Cleanup all of it separately.
 94	 */
 95	if (!c) {
 96		clear_cpu_cap(&boot_cpu_data, feature);
 97		set_bit(feature, (unsigned long *)cpu_caps_cleared);
 98	} else {
 99		clear_bit(feature, (unsigned long *)c->x86_capability);
100	}
101}
102
103/* Take the capabilities and the BUG bits into account */
104#define MAX_FEATURE_BITS ((NCAPINTS + NBUGINTS) * sizeof(u32) * 8)
105
106static void do_clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
107{
108	DECLARE_BITMAP(disable, MAX_FEATURE_BITS);
109	const struct cpuid_dep *d;
110	bool changed;
111
112	if (WARN_ON(feature >= MAX_FEATURE_BITS))
113		return;
114
115	clear_feature(c, feature);
116
117	/* Collect all features to disable, handling dependencies */
118	memset(disable, 0, sizeof(disable));
119	__set_bit(feature, disable);
120
121	/* Loop until we get a stable state. */
122	do {
123		changed = false;
124		for (d = cpuid_deps; d->feature; d++) {
125			if (!test_bit(d->depends, disable))
126				continue;
127			if (__test_and_set_bit(d->feature, disable))
128				continue;
129
130			changed = true;
131			clear_feature(c, d->feature);
132		}
133	} while (changed);
134}
135
136void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
137{
138	do_clear_cpu_cap(c, feature);
139}
140
141void setup_clear_cpu_cap(unsigned int feature)
142{
143	do_clear_cpu_cap(NULL, feature);
144}