• Jeff Dike's avatar
    [PATCH] uml: host VDSO fix · 14251809
    Jeff Dike authored
    This fixes a problem seen by a number of people running UML on newer host
    kernels.  init would hang with an infinite segfault loop.
    It turns out that the host kernel was providing a AT_SYSINFO_EHDR of
    0xffffe000, which faked UML into believing that the host VDSO page could be
    reused.  However, AT_SYSINFO pointed into the middle of the address space, and
    was unmapped as a result.  Because UML was providing AT_SYSINFO_EHDR and
    AT_SYSINFO to its own processes, these would branch to nowhere when trying to
    use the VDSO.
    The fix is to also check the location of AT_SYSINFO when deciding whether to
    use the host's VDSO.
    Signed-off-by: default avatarJeff Dike <jdike@addtoit.com>
    Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
elf_aux.c 2.11 KB