Re: [TOMOYO 1/2] tomoyo: add Documentation/tomoyo.txt

Tetsuo Handa
2009-05-01T13:07:44Z

Sorry for delayed response.

Pavel Machek wrote:
> 2.5 Memory Allocation Rules
>
> In TOMOYO Linux, memory allocated for holding access permissions and
> words are never freed. There is no way except rebooting the system
> that can free unneeded memory.
>
> But don't worry. The policy seldom changes after you start production
> mode. By tuning policy before starting production mode, you can reduce
> memory usage to (usually) less than 1 MB.
>
> ....does that mean that it leaks memory by design?

This is memory leak, but *controlled* memory allocation with a strategy for
avoiding memory fragmentation and reducing memory usage. kstrdup()ing string
data produces partially unused memory block since string data's length is
unlikely power of two. Therefore, TOMOYO allocates memory in PAGE_SIZE bytes
block and embeds string data as much as possible.
TOMOYO does not continue allocating forever.