On Mit, 2008-01-23 at 18:31 +0530, Manish Katiyar wrote: [...] > So If i do a kzalloc() in my module and then unload my module without > freeing it, it will be a memory leak...........Am i right ?? .. Or the Yes. > kernel is intelligent enough to check and free those memory buffers > during unload of the module ? No. That is actually a not-trivial problem[0] as you want to kfree() a buffer when the last pointer to it vanishes. And there is no way (except explicit coding it that way) to e.g. have automatic reference-counting like the typical scripting language (perl, php, ...) or Java. For a kernel, there a lots of places where reference counting is just a waste of memory and CPU power so no one needs/want's it there. Next point is: Module unloading happens quite seldom in real life. So it makes no sense to invest signifikant amount of work just for that one operation (and there are voice who propose to never unload a module in real life). Next: Module unloading is not the only source of memory leaks. So you have to make sure anyways that your module doesn't loose memory. Typical error is to allocate memory in an open() sys-call-handler and forget to free it on a close() handler. Bernd [0]: Google for "garbage collection". -- Firmix Software GmbH http://www.firmix.at/ mobil: +43 664 4416156 fax: +43 1 7890849-55 Embedded Linux Development and Services -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
