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x86/cpu: Remove "nosmep"

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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
This commit is contained in:
Borislav Petkov 2022-01-27 12:56:24 +01:00
parent dbae0a934f
commit 385d2ae0a1
3 changed files with 3 additions and 10 deletions
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2
Documentation/admin-guide/kernel-parameters.txt
View File

@ -3465,7 +3465,7 @@
Disable SMAP (Supervisor Mode Access Prevention)
even if it is supported by processor.
nosmep [X86,PPC64s]
nosmep [PPC64s]
Disable SMEP (Supervisor Mode Execution Prevention)
even if it is supported by processor.

4
Documentation/x86/cpuinfo.rst
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@ -140,8 +140,8 @@ from #define X86_FEATURE_UMIP (16*32 + 2).
In addition, there exists a variety of custom command-line parameters that
disable specific features. The list of parameters includes, but is not limited
to, nofsgsbase, and nosmep. 5-level paging can also be disabled using
"no5lvl". SMEP is disabled with the aforementioned parameter.
to, nofsgsbase, nosgx, noxsave, etc. 5-level paging can also be disabled using
"no5lvl".
e: The feature was known to be non-functional.
----------------------------------------------

7
arch/x86/kernel/cpu/common.c
View File

@ -369,13 +369,6 @@ static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
}
#endif
static __init int setup_disable_smep(char *arg)
{
setup_clear_cpu_cap(X86_FEATURE_SMEP);
return 1;
}
__setup("nosmep", setup_disable_smep);
static __always_inline void setup_smep(struct cpuinfo_x86 *c)
{
if (cpu_has(c, X86_FEATURE_SMEP))