From: Carsten Otte 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 Signed-off-by: Martin Schwidefsky --- arch/s390/mm/pgtable.c | 4 ++++ 1 file changed, 4 insertions(+) Index: quilt-2.6/arch/s390/mm/pgtable.c =================================================================== --- quilt-2.6.orig/arch/s390/mm/pgtable.c +++ quilt-2.6/arch/s390/mm/pgtable.c @@ -256,6 +256,10 @@ 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; -- blue skies, Martin. "Reality continues to ruin my life." - Calvin. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/