| /* 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_FMA, 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_GFNI, X86_FEATURE_AVX512VL }, |
| { X86_FEATURE_VAES, X86_FEATURE_AVX512VL }, |
| { X86_FEATURE_VPCLMULQDQ, 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); |
| } |