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  • David Hildenbrand's avatar
    binfmt: remove support for em86 (alpha only) · 6208721f
    David Hildenbrand authored
    We have a fairly specific alpha binary loader in Linux: running x86
    (i386, i486) binaries via the em86 [1] emulator. As noted in the Kconfig
    option, the same behavior can be achieved via binfmt_misc, for example,
    more nowadays used for running qemu-user.
    
    An example on how to get binfmt_misc running with em86 can be found in
    Documentation/admin-guide/binfmt-misc.rst
    
    The defconfig does not have CONFIG_BINFMT_EM86=y set. And doing a
    	make defconfig && make olddefconfig
    results in
    	# CONFIG_BINFMT_EM86 is not set
    
    ... as we don't seem to have any supported Linux distirbution for alpha
    anymore, there isn't really any "default" user of that feature anymore.
    
    Searching for "CONFIG_BINFMT_EM86=y" reveals mostly discussions from
    around 20 years ago, like [2] describing how to get netscape via em86
    running via em86, or [3] discussing that running wine or installing
    Win 3.11 through em86 would be a nice feature.
    
    The latest binaries available for em86 are from 2000, version 2.2.1 [4] --
    which translates to "unsupported"; further, em86 doesn't even work with
    glibc-2.x but only with glibc-2.0 [4, 5]. These are clear signs that
    there might not be too many em86 users out there, especially users
    relying on modern Linux kernels.
    
    Even though the code footprint is relatively small, let's just get rid
    of this blast from the past that's effectively unused.
    
    [1] http://ftp.dreamtime.org/pub/linux/Linux-Alpha/em86/v0.4/docs/em86.html
    [2] https://static.lwn.net/1998/1119/a/alpha-netscape.html
    [3] https://groups.google.com/g/linux.debian.alpha/c/AkGuQHeCe0Y
    [4] http://zeniv.linux.org.uk/pub/linux/alpha/em86/v2.2-1/relnotes.2.2.1.html
    [5] https://forum.teamspeak.com/archive/index.php/t-1477.html
    
    
    
    Cc: Alexander Viro <viro@zeniv.linux.org.uk>
    Cc: Richard Henderson <rth@twiddle.net>
    Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
    Cc: Matt Turner <mattst88@gmail.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Cc: Jonathan Corbet <corbet@lwn.net>
    Cc: linux-fsdevel@vger.kernel.org
    Cc: linux-api@vger.kernel.org
    Cc: linux-alpha@vger.kernel.org
    Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
    Signed-off-by: default avatarMatt Turner <mattst88@gmail.com>
    6208721f