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SubjectRe: /proc/sys/kernel/pid_max issues
Hi!

> > this is a pretty sweeping assertion. Would you
> > care to mention a few examples of such hazards?
>
> kill(12345,9)
> setpriority(PRIO_PROCESS,12345,-20)
> sched_setscheduler(12345, SCHED_FIFO, &sp)
>
> Prior to the call being handled, the process may
> die and be replaced. Some random innocent process,
> or a not-so-innocent one, will get acted upon by
> mistake. This is broken and dangerous.
>
> Well, it's in the UNIX standard. The best one can
> do is to make the race window hard to hit, with LRU.

Well, you could create new state "DEAD" and enforce that every process stays there for
5 seconds after death. Throttle fork if no pids are free. Hide "DEAD" processes from ps/top.
Pavel
--
64 bytes from 195.113.31.123: icmp_seq=28 ttl=51 time=448769.1 ms

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