diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 49 |
1 files changed, 18 insertions, 31 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 44aec5d4dfaf..fefd9b7e93e1 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -259,48 +259,36 @@ static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c) } #endif -static int disable_smep __cpuinitdata; static __init int setup_disable_smep(char *arg) { - disable_smep = 1; + setup_clear_cpu_cap(X86_FEATURE_SMEP); return 1; } __setup("nosmep", setup_disable_smep); -static __cpuinit void setup_smep(struct cpuinfo_x86 *c) +static __always_inline void setup_smep(struct cpuinfo_x86 *c) { - if (cpu_has(c, X86_FEATURE_SMEP)) { - if (unlikely(disable_smep)) { - setup_clear_cpu_cap(X86_FEATURE_SMEP); - clear_in_cr4(X86_CR4_SMEP); - } else - set_in_cr4(X86_CR4_SMEP); - } + if (cpu_has(c, X86_FEATURE_SMEP)) + set_in_cr4(X86_CR4_SMEP); } -static int disable_smap __cpuinitdata; static __init int setup_disable_smap(char *arg) { - disable_smap = 1; + setup_clear_cpu_cap(X86_FEATURE_SMAP); return 1; } __setup("nosmap", setup_disable_smap); -static __cpuinit void setup_smap(struct cpuinfo_x86 *c) +static __always_inline void setup_smap(struct cpuinfo_x86 *c) { - if (cpu_has(c, X86_FEATURE_SMAP)) { - if (unlikely(disable_smap)) { - setup_clear_cpu_cap(X86_FEATURE_SMAP); - clear_in_cr4(X86_CR4_SMAP); - } else { - set_in_cr4(X86_CR4_SMAP); - /* - * Don't use clac() here since alternatives - * haven't run yet... - */ - asm volatile(__stringify(__ASM_CLAC) ::: "memory"); - } - } + unsigned long eflags; + + /* This should have been cleared long ago */ + raw_local_save_flags(eflags); + BUG_ON(eflags & X86_EFLAGS_AC); + + if (cpu_has(c, X86_FEATURE_SMAP)) + set_in_cr4(X86_CR4_SMAP); } /* @@ -737,9 +725,6 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c) c->cpu_index = 0; filter_cpuid_features(c, false); - setup_smep(c); - setup_smap(c); - if (this_cpu->c_bsp_init) this_cpu->c_bsp_init(c); } @@ -824,8 +809,6 @@ static void __cpuinit generic_identify(struct cpuinfo_x86 *c) c->phys_proc_id = c->initial_apicid; } - setup_smep(c); - get_model_name(c); /* Default name */ detect_nopl(c); @@ -890,6 +873,10 @@ static void __cpuinit identify_cpu(struct cpuinfo_x86 *c) /* Disable the PN if appropriate */ squash_the_stupid_serial_number(c); + /* Set up SMEP/SMAP */ + setup_smep(c); + setup_smap(c); + /* * The vendor-specific functions might have changed features. * Now we do "generic changes." |