Commit c949110e authored by Borislav Petkov's avatar Borislav Petkov
Browse files

x86/cpu: Remove "nosep" 



That chicken bit was added by

  4f886511 ("[PATCH] i386: allow disabling X86_FEATURE_SEP at boot")

but measuring int80 vsyscall performance on 32-bit doesn't matter
anymore.

If still needed, one can boot with

  clearcpuid=sep

to disable that feature for testing.

Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-3-bp@alien8.de
parent 1625c833

Documentation/admin-guide/kernel-parameters.txt

+0 −2
Original line number Diff line number Diff line
@@ -3665,8 +3665,6 @@ 


	nosbagart	[IA-64]



	nosep		[BUGS=X86-32] Disables x86 SYSENTER/SYSEXIT support.



	nosgx		[X86-64,SGX] Disables Intel SGX kernel support.



	nosmp		[SMP] Tells an SMP kernel to act as a UP kernel,

arch/x86/kernel/cpu/common.c

+0 −7
Original line number Diff line number Diff line
@@ -298,13 +298,6 @@ static int __init cachesize_setup(char *str) 
}

__setup("cachesize=", cachesize_setup);



static int __init x86_sep_setup(char *s)

{

	setup_clear_cpu_cap(X86_FEATURE_SEP);

	return 1;

}

__setup("nosep", x86_sep_setup);



/* Standard macro to see if a specific flag is changeable */

static inline int flag_is_changeable_p(u32 flag)

{