[PATCH v2 2/6] x86/cpu: Remove "nosep"

Borislav Petkov
2022-01-27T11:56:42Z

From: Borislav Petkov <bp@suse.de>

That chicken bit was added by

4f88651125e2 ("[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>
---
Documentation/admin-guide/kernel-parameters.txt | 2 --
arch/x86/kernel/cpu/common.c | 7 -------
2 files changed, 9 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index b67d0cf27997..2b35a45c2fd3 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3599,8 +3599,6 @@

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,
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index aaac18d800a4..f394851db082 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -220,13 +220,6 @@ 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)
{
--
2.29.2