Messages in this thread | | | Date | Wed, 26 Nov 1997 12:16:12 -0500 (EST) | From | "Mark H. Wood" <> | Subject | Re: pageable page tables |
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On Tue, 25 Nov 1997, Ralf Baechle wrote:
> On Tue, Nov 25, 1997 at 09:37:00PM +0100, Rik van Riel wrote: > > > Another concern is that users can grab _all_ of system memory > > by having several processes do a 2GB mmap of /dev/zero... > > This 'doesn't take any memory' so they can take up as much > > (non-pageable) pagetable memory as they want. > > In fact, this is the main reason people asked me if I could look > > into this... This is one of the biggest denial-of-service holes > > still left. (ssstt) > > So the resource accounting should count those pages also.
Yes! This was one of the strange ideas I had to get used to with OpenVMS, but it's also a big win for system management. A file's header(s) get(s) charged against your disk quota just like the data blocks; your page table pages get charged against your VM quota; etc.
Mark H. Wood, Lead System Programmer MWOOD@INDYVAX.IUPUI.EDU Those who will not learn from history are doomed to reimplement it.
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