s390/stacktrace: Use break instead of return statement

arch_stack_walk_user_common() contains a return statement instead of a
break statement in case store_ip() fails while trying to store a callchain
entry of a user space process.
This may lead to a missing pagefault_enable() call.

If this happens any subsequent page fault of the process won't be resolved
by the page fault handler and this in turn will lead to the process being
killed.

Use a break instead of a return statement to fix this.

Fixes: ebd912f ("s390/stacktrace: Merge perf_callchain_user() and arch_stack_walk_user()")
Cc: [email protected]
Reviewed-by: Jens Remus <[email protected]>
Signed-off-by: Heiko Carstens <[email protected]>

Author: hcahca

arch/s390/kernel/stacktrace.c

@@ -151,7 +151,7 @@ void arch_stack_walk_user_common(stack_trace_consume_fn consume_entry, void *coo
 				break;
 		}
 		if (!store_ip(consume_entry, cookie, entry, perf, ip))
-			return;
+			break;
 		first = false;
 	}
 	pagefault_enable();