On February 17, 2017 3:02:33 PM PST, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote: >On Fri, Feb 17, 2017 at 1:01 PM, Linus Torvalds ><torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: >> On Fri, Feb 17, 2017 at 12:12 PM, Andy Lutomirski ><luto@xxxxxxxxxxxxxx> wrote: >>> >>> At the very least, I'd want to see >>> MAP_FIXED_BUT_DONT_BLOODY_UNMAP_ANYTHING. I *hate* the current >>> interface. >> >> That's unrelated, but I guess w could add a MAP_NOUNMAP flag, and >then >> you can use MAP_FIXED | MAP_NOUNMAP or something. >> >> But that has nothing to do with the 47-vs-56 bit issue. >> >>> How about MAP_LIMIT where the address passed in is interpreted as an >>> upper bound instead of a fixed address? >> >> Again, that's a unrelated semantic issue. Right now - if you don't >> pass in MAP_FIXED at all, the "addr" argument is used as a starting >> value for deciding where to find an unmapped area. But there is no >way >> to specify the end. That would basically be what the process control >> thing would be (not per-system-call, but per-thread ). >> > >What I'm trying to say is: if we're going to do the route of 48-bit >limit unless a specific mmap call requests otherwise, can we at least >have an interface that doesn't suck? Let's not, please. But we really want this interface anyway. -- Sent from my Android device with K-9 Mail. Please excuse my brevity.
