projects / mirror_ubuntu-jammy-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 1353ebb4 | 2 | /* |
| 1353ebb4 JF |
3 | * Copyright (C) 1994 Linus Torvalds |
| 4 | * | |
| 5 | * Cyrix stuff, June 1998 by: | |
| 6 | * - Rafael R. Reilova (moved everything from head.S), | |
| 7 | * <rreilova@ececs.uc.edu> | |
| 8 | * - Channing Corn (tests & fixes), | |
| 9 | * - Andrew D. Balsa (code cleanup). | |
| 10 | */ | |
| 11 | #include <linux/init.h> | |
| 12 | #include <linux/utsname.h> | |
| 61dc0f55 | 13 | #include <linux/cpu.h> |
| 91eb1b79 | 14 | #include <asm/bugs.h> |
| 1353ebb4 | 15 | #include <asm/processor.h> |
| 7ebad705 | 16 | #include <asm/processor-flags.h> |
| 952f07ec | 17 | #include <asm/fpu/internal.h> |
| 1353ebb4 JF |
18 | #include <asm/msr.h> |
| 19 | #include <asm/paravirt.h> | |
| 20 | #include <asm/alternative.h> | |
| 62a67e12 | 21 | #include <asm/pgtable.h> |
| d1163651 | 22 | #include <asm/set_memory.h> |
| 1353ebb4 | 23 | |
| 1353ebb4 JF |
24 | void __init check_bugs(void) |
| 25 | { | |
| 26 | identify_boot_cpu(); | |
| 55a36b65 | 27 | |
| 62a67e12 BP |
28 | if (!IS_ENABLED(CONFIG_SMP)) { |
| 29 | pr_info("CPU: "); | |
| 30 | print_cpu_info(&boot_cpu_data); | |
| 31 | } | |
| 32 | ||
| 33 | #ifdef CONFIG_X86_32 | |
| 55a36b65 BP |
34 | /* |
| 35 | * Check whether we are able to run this kernel safely on SMP. | |
| 36 | * | |
| 37 | * - i386 is no longer supported. | |
| 38 | * - In order to run on anything without a TSC, we need to be | |
| 39 | * compiled for a i486. | |
| 40 | */ | |
| 41 | if (boot_cpu_data.x86 < 4) | |
| 42 | panic("Kernel requires i486+ for 'invlpg' and other features"); | |
| 43 | ||
| bfe4bb15 MV |
44 | init_utsname()->machine[1] = |
| 45 | '0' + (boot_cpu_data.x86 > 6 ? 6 : boot_cpu_data.x86); | |
| 1353ebb4 | 46 | alternative_instructions(); |
| 304bceda | 47 | |
| 4d164092 | 48 | fpu__init_check_bugs(); |
| 62a67e12 BP |
49 | #else /* CONFIG_X86_64 */ |
| 50 | alternative_instructions(); | |
| 51 | ||
| 52 | /* | |
| 53 | * Make sure the first 2MB area is not mapped by huge pages | |
| 54 | * There are typically fixed size MTRRs in there and overlapping | |
| 55 | * MTRRs into large pages causes slow downs. | |
| 56 | * | |
| 57 | * Right now we don't do that with gbpages because there seems | |
| 58 | * very little benefit for that case. | |
| 59 | */ | |
| 60 | if (!direct_gbpages) | |
| 61 | set_memory_4k((unsigned long)__va(0), 1); | |
| 62 | #endif | |
| 1353ebb4 | 63 | } |
| 61dc0f55 TG |
64 | |
| 65 | #ifdef CONFIG_SYSFS | |
| 66 | ssize_t cpu_show_meltdown(struct device *dev, | |
| 67 | struct device_attribute *attr, char *buf) | |
| 68 | { | |
| 69 | if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN)) | |
| 70 | return sprintf(buf, "Not affected\n"); | |
| 71 | if (boot_cpu_has(X86_FEATURE_PTI)) | |
| 72 | return sprintf(buf, "Mitigation: PTI\n"); | |
| 73 | return sprintf(buf, "Vulnerable\n"); | |
| 74 | } | |
| 75 | ||
| 76 | ssize_t cpu_show_spectre_v1(struct device *dev, | |
| 77 | struct device_attribute *attr, char *buf) | |
| 78 | { | |
| 79 | if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1)) | |
| 80 | return sprintf(buf, "Not affected\n"); | |
| 81 | return sprintf(buf, "Vulnerable\n"); | |
| 82 | } | |
| 83 | ||
| 84 | ssize_t cpu_show_spectre_v2(struct device *dev, | |
| 85 | struct device_attribute *attr, char *buf) | |
| 86 | { | |
| 87 | if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2)) | |
| 88 | return sprintf(buf, "Not affected\n"); | |
| 89 | return sprintf(buf, "Vulnerable\n"); | |
| 90 | } | |
| 91 | #endif |