ptrace_wake_up() clears tracee->exit_code, this is racy and no longer needed.
This was needed previously when ->exit_code was checked by callbacks. Now
->exit_code is only used by do_wait(), and we have no reasons to clear it.
If the tracee exits or stops again ->exit_code will be correctly updated
anyway, until then it has no effect.
Also, update the comment.
---
kernel/ptrace.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
--- PU/kernel/ptrace.c~91_CLEANUP_FIX_WAKEUP 2009-10-14 13:18:45.000000000
+0200
+++ PU/kernel/ptrace.c 2009-10-15 20:09:10.000000000 +0200
@@ -944,24 +944,24 @@ void ptrace_notify_stop(struct task_stru
utrace_engine_put(engine);
}
-static void ptrace_wake_up( struct task_struct *tracee,
+static void ptrace_wake_up(struct task_struct *tracee,
struct utrace_engine *engine,
enum utrace_resume_action action,
bool force_wakeup)
{
if (force_wakeup) {
unsigned long flags;
-
- /* preserve the compatibility bug */
- if (!lock_task_sighand(tracee, &flags))
- return;
- tracee->signal->flags &= ~SIGNAL_STOP_STOPPED;
- unlock_task_sighand(tracee, &flags);
+ /*
+ * Preserve the compatibility bug. Historically ptrace
+ * wakes up the tracee even if it should not. Clear
+ * SIGNAL_STOP_STOPPED for utrace_wakeup().
+ */
+ if (lock_task_sighand(tracee, &flags)) {
+ tracee->signal->flags &= ~SIGNAL_STOP_STOPPED;
+ unlock_task_sighand(tracee, &flags);
+ }
}
- // XXX: FIXME!!! racy.
- tracee->exit_code = 0;
-
ptrace_context(engine)->stop_code = 0;
utrace_control(tracee, engine, action);
}
