• Andrew Morton's avatar
    uaccess: reimplement probe_kernel_address() using probe_kernel_read() · 0ab32b6f
    Andrew Morton authored
    probe_kernel_address() is basically the same as the (later added)
    probe_kernel_read().
    
    The return value on EFAULT is a bit different: probe_kernel_address()
    returns number-of-bytes-not-copied whereas probe_kernel_read() returns
    -EFAULT.  All callers have been checked, none cared.
    
    probe_kernel_read() can be overridden by the architecture whereas
    probe_kernel_address() cannot.  parisc, blackfin and um do this, to insert
    additional checking.  Hence this patch possibly fixes obscure bugs,
    although there are only two probe_kernel_address() callsites outside
    arch/.
    
    My first attempt involved removing probe_kernel_address() entirely and
    converting all callsites to use probe_kernel_read() directly, but that got
    tiresome.
    
    This patch shrinks mm/slab_common.o by 218 bytes.  For a single
    probe_kernel_address() callsite.
    
    Cc: Steven Miao <realmz6@gmail.com>
    Cc: Jeff Dike <jdike@addtoit.com>
    Cc: Richard Weinberger <richard@nod.at>
    Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
    Cc: Helge Deller <deller@gmx.de>
    Cc: Ingo Molnar <mingo@elte.hu>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    0ab32b6f
alignment.c 26.6 KB