Eric Lee / smarc-ti-linux-kernel

15 Dec, 2014

2 commits

  • 72e9b5fe9   x86, mpx: Give MPX a real config option prompt ... Browse Code »

    Give MPX a real config option. The CPUs that support it (referenced
    here):

    https://software.intel.com/en-us/forums/topic/402393

    are not available publicly yet. Right now only the software emulator
    provides MPX for the general public.

    [ tglx: Make it default off. There is no point in having it on right
    now as no hardware and no proper tooling support are available ]

    Signed-off-by: Dave Hansen
    Cc: Dave Hansen
    Link: http://lkml.kernel.org/r/20141212183836.2569D58D@viggo.jf.intel.com
    Signed-off-by: Thomas Gleixner

    Dave Hansen
     
  • 010e593b1   x86, mpx: Update documentation ... Browse Code »

    I was writing some MPX test programs and realized that the
    current design makes it tricky. I did something like:

    bndcfgu |= bnd_dir | BNDCFGU_ENABLE;
    xrstor();
    printf("xrstor done");
    // #BR bounds exception here
    prctl(MPX_ENABLE_MANAGEMENT);

    and then compiled the app with "-fcheck-pointer-bounds -mmpx"
    to enable MPX instrumentation.

    The problem is that there is MPX instrumentation inserted in
    to the area of the printf(). The kernel gets a bounds exception
    and since management isn't yet enabled, it SIGSEGV's.

    Add a bit to the documentation to explain a way around this and
    where apps need to be careful.

    Signed-off-by: Dave Hansen
    Cc: Dave Hansen
    Link: http://lkml.kernel.org/r/20141212183835.8C581B3E@viggo.jf.intel.com
    Signed-off-by: Thomas Gleixner

    Dave Hansen
     

18 Nov, 2014

1 commit

  • 577656364   x86, mpx: Add documentation on Intel MPX ... Browse Code »

    This patch adds the Documentation/x86/intel_mpx.txt file with some
    information about Intel MPX.

    Signed-off-by: Qiaowei Ren
    Signed-off-by: Dave Hansen
    Cc: linux-mm@kvack.org
    Cc: linux-mips@linux-mips.org
    Cc: Dave Hansen
    Link: http://lkml.kernel.org/r/20141114151832.7FDB1720@viggo.jf.intel.com
    Signed-off-by: Thomas Gleixner

    Qiaowei Ren