Re: Linux 2.3.39 has 32bit uid. What about 32bit pid?

[Alan Cox]

> I think we should change __kernel_pid_t now that we are changing __kernel_uid_t.
> 
> a) It is easy - easier than the change to larger uid.
> Roughly speaking the only change is in the ipc structs.
> (The other part of the change is in /proc.)

Do libc5 and glibc give the illusion of a 32bit pid - I thought they didnt

> b) The reuse of pids causes security problems.

No.. people cause security problems.

> get_pid() {
> 	return ++last_pid;
> }

That loses your security advantage

> (On the other hand, if we do not enlarge the pid_t size, then
> a bitmap with pids_in_use would make get_pid() much faster.)

ffz() on pids_in_use yep..

Alan