Svante Signell, on Wed 31 Aug 2016 12:35:26 +0200, wrote: > The attached patch changes this fixing the previous: > check_setpriority: can't set priority: Permission denied > > - prierr = __task_priority (task, NICE_TO_MACH_PRIORITY (prio), 1); > + prierr = __task_priority (task, NICE_TO_MACH_PRIORITY (prio), 0);
Err, but then that makes change_threads false, i.e. the task_priority() call will not change the priorities of all threads of the task, which as you say is the POSIX behavior: > According to setpriority(2) and POSIX the nice value should be > per-process not per-thread. So this "fix" your testcase by making the function not do what it is supposed to do... Re-read your test again: it requests nice -19, i.e. something which is reserved to root. No wonder you are getting a permission denied. The actual bug here is that task_priority seems not to check whether the priority is allowed when change_threads is false. Samuel
