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| author | Joursoir <chat@joursoir.net> | 2023-05-04 23:25:03 +0400 |
|---|---|---|
| committer | Joursoir <chat@joursoir.net> | 2023-06-05 23:25:03 +0400 |
| commit | a43cba140c2131ad3eab04e5723d1c49b0306a4f (patch) | |
| tree | bdc74685e2a7162c02bf8d8dc482f695dfcc3a85 | |
| parent | 950e3df3bd7446b37b92eb07f5ca514129786084 (diff) | |
| download | cpui-drv-a43cba140c2131ad3eab04e5723d1c49b0306a4f.tar.gz cpui-drv-a43cba140c2131ad3eab04e5723d1c49b0306a4f.tar.bz2 cpui-drv-a43cba140c2131ad3eab04e5723d1c49b0306a4f.zip | |
obtain EFER MSR
| -rw-r--r-- | cpui-drv.c | 19 |
1 files changed, 19 insertions, 0 deletions
@@ -1,6 +1,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/module.h> +#include <asm/msr.h> enum feature_information { FEATURES_01_ECX = 0, @@ -193,6 +194,7 @@ static void get_cpu_features(struct cpui_info *cpu) static int __init cpui_init(void) { + uint64_t value; struct cpui_info *cpu; if (!have_cpuid_p()) { @@ -208,6 +210,23 @@ static int __init cpui_init(void) pr_info("Identity string = %s\n", cpu->vendor_string); get_cpu_features(cpu); + + if (!test_cpu_feat(cpu, FEATURE_MSR)) { + pr_err("The RDMSR and WRMSR instructions are NOT supported. Aborting.\n"); + return 1; + } + + /* Check if IA32_EFER is present */ + if (test_cpu_feat(cpu, FEATURE_EXECD) || test_cpu_feat(cpu, FEATURE_LM)) { + rdmsrl(MSR_EFER, value); + pr_info("IA32_EFER = 0x%016llx\n", value); + pr_info("\tIA32_EFER.SCE (System Call Extensions) = %llu\n", (value & EFER_SCE) >> _EFER_SCE); + pr_info("\tIA32_EFER.LME (Long Mode Enable) = %llu\n", (value & EFER_LME) >> _EFER_LME); + pr_info("\tIA32_EFER.LMA (Long Mode Active) = %llu\n", (value & EFER_LMA) >> _EFER_LMA); + pr_info("\tIA32_EFER.NXE (No-Execute Enable) = %llu\n", (value & EFER_NX) >> _EFER_NX); + pr_info("\tIA32_EFER.SVME (Secure Virtual Machine Enable) = %llu\n", (value & EFER_SVME) >> _EFER_SVME); + pr_info("\tIA32_EFER.LMSLE (Long Mode Segment Limit Enable) = %llu\n", (value & EFER_LMSLE) >> _EFER_LMSLE); + } return 0; } |