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[[!tag open_issue_gnumach open_issue_mig]]

There is a `master-x86_64` GNU Mach branch.  As of 2012-11-20, it only supports
the [[microkernel/mach/gnumach/ports/Xen]] platform.


# IRC, freenode, #hurd, 2011-10-16

    <youpi> it'd be really good to have a 64bit kernel, no need to care about
      addressing space :)
    <braunr> yes a 64 bits kernel would be nice
    <braunr> i guess it wouldn't be too hard to have a special mach kernel for
      64 bits processors, but 32 bits userland only
    <youpi> well, it means tinkering with mig

[[mig_portable_rpc_declarations]].


# IRC, freenode, #hurd, 2012-10-03

    <braunr> youpi: just so you know in case you try the master-x86_64 with
      grub
    <braunr> youpi: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=689509
    <youpi> ok, thx
    <braunr> the squeeze version is fine but i had to patch the wheezy/sid one
    <youpi> I actually hadn't hoped to boot into 64bit directly from grub
    <braunr> youpi: there is code in viengoos that could be reused
    <braunr> i've been thinking about it for a time now
    <youpi> ok
    <braunr> the two easiest ways are 1/ the viengoos one (a -m32 object file
      converted with objcopy as an embedded loader)
    <braunr> and 2/ establishing an identity mapping using 4x1 GB large pages
      and switching to long mode, then jumping to c code to complete the
      initialization
    <braunr> i think i'll go the second way with x15, so you'll have the two :)


## IRC, freenode, #hurd, 2013-07-02

In context of [[mondriaan_memory_protection]].

    <xscript> BTW, it's not like I have an infinite amount of time for this,
      but having 64-bit support would be valuable for me, so I might contribute
      that back if it's not a too monumental task
    <xscript> I saw some discussions about 32bit apps on top of 64bit mach, but
      I'd like a full 64bit system
    <xscript> any clues?
    <xscript> I suppose the compiler support is all there already
    <xscript> is MIG (and mach) the only piece missing?
    <braunr> the problem is the interfaces themselves
    <braunr> type widths
    <braunr> as passed between userspace and kernel


## IRC, OFTC, #debian-hurd, 2013-10-05

    <dharc> and what about 64 bit support, almost done?
    <youpi> kernel part is done
    <youpi> MIG 32/64 trnaslation missing

[[mig_portable_rpc_declarations]].