Hi - "Keshavamurthy, Anil S" <[EMAIL PROTECTED]> writes:
> [...] > > Really? What possible problems can occur? The worst that occurs > > to me is that if someone forgets to call the commit function, the > > kprobes will still be disabled, but memory won't be recycled for a > > while. [...] > > Yes, Have you looked at the code? A little, but we were talking more about the interface than the implementation. > If someone forgets to call the commit function, the kprobe will be > disabled and yes the memory won't be recycled but the worst problem > is that if the probe is on a module function then that module can't > be unloaded at all [...] I believe there is already a kprobes patch in the queue for enumerating active probes in some /proc file. Should a module be locked into memory for such a reason, finding the culprit should not be difficult. > Hence, my suggestion would be to call them as disable_kprobe() > (instead of unregister_kprobes_fast() which is confusing and error > prone) and also to provide an opposite function to reenable_kprobe() > and finally provide unregister_disabled_kprobes() which is > essentially the same as commit_kprobes(). One problem with this idea is that if the unregister_fast()=disable() is to become reversible, then the renamed commit_kprobes() will no longer be indempotent. There can no longer be a single system-wide deferred-kprobe-cleanup list, since individual kprobes clients might want to reinstate their probes in the future. > > Would it be possible to allay even that concern with an automated > > deferred/periodic commit? > > > I would recomand that users call unregister_disabled_kprobes() explictly. But this would solve both problems (memory leaks and outstanding reference counts on modules). In this variant, unregister_kprobes_fast could replace unregister_kprobes outright, and the (builtin deferred) commit function would need not be exported. - FChE - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
