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    Subject(XFree86) mmap of /proc/XXX/mem

    To initialize secondary graphics cards for the multi-head
    feature on XFree86 3.9 it needs to execute the boot up sequence
    in the Video BIOS. Also the drivers may make use of Video BIOS
    int calls when setting up video modes. On Linux/x86 we use the
    vm86-mode to execute the Video BIOS routines. On non-Intel
    platforms an emulator is available.

    The vm86 mode requires the execute environment (int vectors,
    system bios image, vram - in short the DOS real mode environment)
    to start at address 0 in virtual address space of the process
    calling vm86(). So far the real mode image is initialized during
    startup for each card that requests it. When a card wants to
    make a BIOS call its real mode image is mapped to address 0
    by mmapping /proc/self/mem. However I have reports mmapping
    /proc/XXX/mem was removed from later versions of the 2.3 branch.

    Is there anybody who knows a workaround for this? If there is
    none - and so far I couldn't think of one myself - I would strongly
    encourage the kernel developer to re-add this feature.


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