[lkml]   [1999]   [Apr]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: verify_area(...) possible problem.
    On Mon, 12 Apr 1999, Linus Torvalds wrote:
    > Basically, you should always use a kernel-space buffer. Just accept that
    > as a fundamental notion, and your life suddenly turns a lot easier.
    > Now, I know about zero-copy. I'm not a big believer in it, but I certainly
    > know about it. And having a kernel buffer does not imply that you can't do
    > zero-copy. It just means that you can' tdo the initial copy to user space.
    > Sounds contradictory? Think "mmap()". It works, it's there, and magically
    > all the problems go away. Don't make the mountain go to Mohammed. Instead,
    > think of your problem the other way around: instead of the kernel writing
    > to user space, think of it as user space asking to see a window of a
    > kernel buffer. You make a device driver that has a mmap() function, and
    > suddenly the device driver can write to kernel memory, and whatever it
    > writes magically shows up in user space too.

    Can some kind soul point me in the right direction here? I mean a code
    example or a page which describes this in detail. Basically I need to have
    a buffer shared between a kernel space and user space.


    Dennis Gerasimov

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

     \ /
      Last update: 2005-03-22 13:51    [W:0.026 / U:0.148 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site