diff options
Diffstat (limited to 'arch/x86/kernel/cpu/intel.c')
| -rw-r--r-- | arch/x86/kernel/cpu/intel.c | 36 |
1 files changed, 0 insertions, 36 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 57473e2c0869..be82cd5841c3 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -32,41 +32,6 @@ #endif /* - * Just in case our CPU detection goes bad, or you have a weird system, - * allow a way to override the automatic disabling of MPX. - */ -static int forcempx; - -static int __init forcempx_setup(char *__unused) -{ - forcempx = 1; - - return 1; -} -__setup("intel-skd-046-workaround=disable", forcempx_setup); - -void check_mpx_erratum(struct cpuinfo_x86 *c) -{ - if (forcempx) - return; - /* - * Turn off the MPX feature on CPUs where SMEP is not - * available or disabled. - * - * Works around Intel Erratum SKD046: "Branch Instructions - * May Initialize MPX Bound Registers Incorrectly". - * - * This might falsely disable MPX on systems without - * SMEP, like Atom processors without SMEP. But there - * is no such hardware known at the moment. - */ - if (cpu_has(c, X86_FEATURE_MPX) && !cpu_has(c, X86_FEATURE_SMEP)) { - setup_clear_cpu_cap(X86_FEATURE_MPX); - pr_warn("x86/mpx: Disabling MPX since SMEP not present\n"); - } -} - -/* * Processors which have self-snooping capability can handle conflicting * memory type across CPUs by snooping its own cache. However, there exists * CPU models in which having conflicting memory types still leads to @@ -330,7 +295,6 @@ static void early_init_intel(struct cpuinfo_x86 *c) c->x86_coreid_bits = get_count_order((ebx >> 16) & 0xff); } - check_mpx_erratum(c); check_memory_type_self_snoop_errata(c); /* |