[S390] avoid STCKF if running in ESA mode

In ESA mode STCKF is not defined even if the facility bit is enabled.
To prevent an illegal operation we must also check if we run a 64 bit kernel.
To make the check perform well add the STCKF bit to the machine flags.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 37394b3413e..c9ffe002519 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -390,6 +390,8 @@ static __init void detect_machine_facilities(void)
                 S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
         if (test_facility(40))
                 S390_lowcore.machine_flags |= MACHINE_FLAG_SPP;
+        if (test_facility(25))
+                S390_lowcore.machine_flags |= MACHINE_FLAG_STCKF;
 #endif
 }