[lkml]   [2007]   [Feb]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [patch 05/11] syslets: core code
On Wed, Feb 14, 2007 at 10:46:29AM +0100, Ingo Molnar ( wrote:
> * Evgeniy Polyakov <> wrote:
> > This will end up badly - I used the same approach in the early kevent
> > days and was proven to have swapable memory for the ring. I think it
> > would be much better to have userspace allocated ring and use
> > copy_to_user() there.
> it is a userspace allocated ring - but pinned down by the kernel.

That's a problem - 1000/512 pages per 'usual' thread ends up with the
whole memory locked by malicious/stupid application (at least on Debian
and Mandrake there is no locked memory limit by default). And if such
a limit exists, this will hurt big-iron applications, which want to used
high-order rings legitimely.

> Ingo

Evgeniy Polyakov
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2007-02-14 11:15    [W:0.734 / U:1.592 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site