There should be no need to disable SMEP anymore.
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-5-bp@alien8.de
Those were added as part of the SMAP enablement but SMAP is currently
an integral part of kernel proper and there's no need to disable it
anymore.
Rip out that functionality. Leave --uaccess default on for objtool as
this is what objtool should do by default anyway.
If still needed - clearcpuid=smap.
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-4-bp@alien8.de
/proc/cpuinfo shows features which the kernel supports. Some of these
flags are derived from CPUID, and others are derived from other sources,
including some that are entirely software-based. Currently, there is
not any documentation in the kernel about how /proc/cpuinfo flags are
generated and what it means when they are missing.
Add documentation for /proc/cpuinfo feature flags enumeration.
Document how and when x86 feature flags are used. Also discuss what
their presence or absence mean for the kernel and users.
Suggested-by: Dave Hansen <dave.hansen@intel.com>
Co-developed-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Kyung Min Park <kyung.min.park@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200831183500.15481-1-kyung.min.park@intel.com