On 11/16, Roland McGrath wrote:
>
> You cited the one most obvious case: utrace_get_signal() has just run, so
> finish_resume_report() has just run and everything is already as we want.
>
> What else?
I think, we can say that finish_resume_report() must be never called
without reporting loop if ->resume = UTRACE_RESUME.
> --- a/kernel/utrace.c
> +++ b/kernel/utrace.c
> @@ -1866,8 +1866,18 @@ void utrace_resume(struct task_struct *t
> */
> report.action = start_report(utrace);
>
> - if (report.action == UTRACE_REPORT &&
> - likely(task->utrace_flags & UTRACE_EVENT(QUIESCE))) {
> + switch (report.action) {
> + case UTRACE_RESUME:
> + /*
> + * Anything we might have done was already handled by
> + * utrace_get_signal(), or this is an entirely spurious
> + * call. (The arch might use TIF_NOTIFY_RESUME for other
> + * purposes as well as calling us.)
> + */
> + return;
Yes, I think this change is right. Will test and report later, but
it "obviously" should fix the testing.
I feel we need some cleanups, but can't suggest anything ;) And can't
convince myself I am 100% sure we don't have other similar issues.
At least, don't we also need the patch below?
Oleg.
--- a/kernel/utrace.c
+++ b/kernel/utrace.c
@@ -2002,7 +2002,7 @@ int utrace_get_signal(struct task_struct
spin_unlock_irq(&task->sighand->siglock);
}
- if (resume > UTRACE_REPORT) {
+ if (resume > UTRACE_REPORT && utrace < UTRACE_RESUME) {
/*
* We only got here to process utrace->resume.
* Despite no callbacks, this report is not spurious.
