[S390] check addressing mode in s390_enable_sie

The sie instruction requires address spaces to be switched
to run proper. This patch verifies that this is the case
in s390_enable_sie, otherwise the kernel would crash badly
as soon as the process runs into sie.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Carsten Otte 2009-03-26 15:23:57 +01:00 committed by Martin Schwidefsky
parent 3324e60aaf
commit 702d9e584f

View File

@ -258,6 +258,10 @@ int s390_enable_sie(void)
struct task_struct *tsk = current;
struct mm_struct *mm, *old_mm;
/* Do we have switched amode? If no, we cannot do sie */
if (!switch_amode)
return -EINVAL;
/* Do we have pgstes? if yes, we are done */
if (tsk->mm->context.has_pgste)
return 0;