s390/tx: allow program interruption filtering in user space

A user space program using the transactional execution facility
should be allowed to do program interrupt filtering. Do not set the
transactional-execution program-interruption-filtering override (PIFO)
bit in CR0.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index 2bc0803..9556905 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -60,11 +60,11 @@
 
 		__ctl_store(cr, 0, 2);
 		cr_new[1] = cr[1];
-		/* Set or clear transaction execution TXC/PIFO bits 8 and 9. */
+		/* Set or clear transaction execution TXC bit 8. */
 		if (task->thread.per_flags & PER_FLAG_NO_TE)
-			cr_new[0] = cr[0] & ~(3UL << 54);
+			cr_new[0] = cr[0] & ~(1UL << 55);
 		else
-			cr_new[0] = cr[0] | (3UL << 54);
+			cr_new[0] = cr[0] | (1UL << 55);
 		/* Set or clear transaction execution TDC bits 62 and 63. */
 		cr_new[2] = cr[2] & ~3UL;
 		if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) {