On Tue, Aug 17, 2004 at 11:18:30PM -0700, Martin J. Bligh wrote: > --Arjan van de Ven wrote (on Wednesday, August 18, 2004 08:11:21 +0200): > > > On Tue, Aug 17, 2004 at 03:18:34PM -0700, Martin J. Bligh wrote: > >> I worry that the current code will allow us to intrude into the > >> reserved stack space with a vma allocation if it's requested at > >> an address too high up. One could argue that they got what they > >> asked for ... but not sure we should be letting them do that? > > > > well even the non-flexmmap code allows this... > > Yeah, wasn't meant as a criticism of the new layout, just a general > improvement, perhaps. > > > what is the problem ? > > Just that if they allocate right up to the stack, we'll go boom shortly > afterwards. I guess the question is ... what exactly are the rules > for stack space reservations? well... unless you have a VERY good reason I would see it as rude to prevent this, I mean, the user *asks* for this address. Posix and co I'm sure don't allow you to deny it unless it's really busy. Or say the user unmaps the stack (after allocating a new one and changing esp).... the kernel then would not allow a new area to be mapped there either.... smells like something the kernel should not enforce to me.