diff options
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/lib/uaccess_mvcos.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/arch/s390/lib/uaccess_mvcos.c b/arch/s390/lib/uaccess_mvcos.c index e2685ff2ec4b..ae97b8df11aa 100644 --- a/arch/s390/lib/uaccess_mvcos.c +++ b/arch/s390/lib/uaccess_mvcos.c @@ -241,9 +241,22 @@ long __strncpy_from_user(char *dst, const char __user *src, long count) } EXPORT_SYMBOL(__strncpy_from_user); +/* + * The uaccess page tabe walk variant can be enforced with the "uaccesspt" + * kernel parameter. This is mainly for debugging purposes. + */ +static int force_uaccess_pt __initdata; + +static int __init parse_uaccess_pt(char *__unused) +{ + force_uaccess_pt = 1; + return 0; +} +early_param("uaccesspt", parse_uaccess_pt); + static int __init uaccess_init(void) { - if (IS_ENABLED(CONFIG_32BIT) || !test_facility(27)) + if (IS_ENABLED(CONFIG_32BIT) || force_uaccess_pt || !test_facility(27)) static_key_slow_dec(&have_mvcos); return 0; } |