Merge tag 'mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/daveh...

[platform/kernel/linux-rpi.git] / arch / x86 / kernel / cpu / intel.c

diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 57473e2..be82cd5 100644 (file)
--- 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);
 
        /*