Re: [PATCH 4/4] add ksm kernel shared memory driver.

Andrea Arcangeli
2009-03-31T15:19:21Z

On Tue, Mar 31, 2009 at 10:09:24AM -0500, Anthony Liguori wrote:
> I don't think the registering of ram should be done via sysfs. That would
> be a pretty bad interface IMHO. But I do think the functionality that
> ksmctl provides along with the security issues I mentioned earlier really
> suggest that there ought to be a separate API for control vs. registration
> and that control API would make a lot of sense as a sysfs API.
>
> If you wanted to explore alternative APIs for registration, madvise() seems
> like the obvious candidate to me.
>
> madvise(start, size, MADV_SHARABLE) seems like a pretty obvious API to me.

madvise to me would sound appropriate, only if ksm would be always-in,
which is not the case as it won't even be built if it's configured to
N.

Besides madvise is sus covered syscall, and this is linux specific detail.