Commits
Fenghua Yu committed de5397ad5b9
x86, cpu: Enable/disable Supervisor Mode Execution Protection Enable/disable newly documented SMEP (Supervisor Mode Execution Protection) CPU feature in kernel. CR4.SMEP (bit 20) is 0 at power-on. If the feature is supported by CPU (X86_FEATURE_SMEP), enable SMEP by setting CR4.SMEP. New kernel option nosmep disables the feature even if the feature is supported by CPU. [ hpa: moved the call to setup_smep() until after the vendor-specific initialization; that ensures that CPUID features are unmasked. We will still run it before we have userspace (never mind uncontrolled userspace). ] Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> LKML-Reference: <1305157865-31727-1-git-send-email-fenghua.yu@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>