Messages in this thread | | | Date | Fri, 20 Oct 2000 13:46:53 -0400 | From | Jeff Garzik <> | Subject | Re: VM_RESERVED [was Re: mapping user space buffer to kernel address space] |
| |
Andrea Arcangeli wrote: > > As to your rvmalloc()/rvfree() changes, I don't think they are safe as-is: > > I think it's the right thing to do, but I don't trust the drivers to > > maintain the right page counts. The code used to mark the pages as > > reserved, which probably means that it hides bad drivers that do not do > > proper reference counting - and I'm not willing to make that kind of > > change at this point. > > The page count of the mapped pages should be ok, it seems those mapped pages > have a reference count of 1 just from the vmalloc allocation and they use > PG_reserved just to skip swap_out, but I feel safer too if the bttv maintainers > will check it and send it to you themself after checking it's correct. (I only > verified that it was compiling correctly)
In any case, we shouldn't modify videodev.c to call vma_reserve()... Let the driver's mmap operation do that or not do that, as it chooses.
Jeff
-- Jeff Garzik | The difference between laziness and Building 1024 | prioritization is the end result. MandrakeSoft | - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
| |