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x86/cpu: Remove "nosep"

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That chicken bit was added by

  4f88651125 ("[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: Borislav Petkov <bp@suse.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-3-bp@alien8.de
This commit is contained in:
Borislav Petkov 2022-01-27 12:56:22 +01:00
parent 1625c833db
commit c949110ef4
2 changed files with 0 additions and 9 deletions
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2
Documentation/admin-guide/kernel-parameters.txt
View File

@ -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,

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

@ -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)
{