s390/uaccess: remove uaccess_primary kernel parameter

get_user() and put_user() are inline functions in the meantime
again. Both will generate the mvcos instruction if compiled
with -march=z10 (or greater).

The kernel parameter "uaccess_primary" can only change the behavior
of out-of-line uaccess functions like copy_from_user() to not use
the mvcos instruction, but not for the above named inlined functions.

Therefore it is quite useless and the parameter can be removed.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 1 insertions, 14 deletions

diff --git a/arch/s390/lib/uaccess.c b/arch/s390/lib/uaccess.c
index 4614d415bb58..0d002a746bec 100644
--- a/arch/s390/lib/uaccess.c
+++ b/arch/s390/lib/uaccess.c
@@ -370,22 +370,9 @@ long __strncpy_from_user(char *dst, const char __user *src, long size)
 }
 EXPORT_SYMBOL(__strncpy_from_user);
 
-/*
- * The "old" uaccess variant without mvcos can be enforced with the
- * uaccess_primary kernel parameter. This is mainly for debugging purposes.
- */
-static int uaccess_primary __initdata;
-
-static int __init parse_uaccess_pt(char *__unused)
-{
-	uaccess_primary = 1;
-	return 0;
-}
-early_param("uaccess_primary", parse_uaccess_pt);
-
 static int __init uaccess_init(void)
 {
-	if (!uaccess_primary && test_facility(27))
+	if (test_facility(27))
 		static_key_slow_inc(&have_mvcos);
 	return 0;
 }