[RFC 0/4] Switching ARC to optimized generic strncpy_from_user

Hi,

This came up when trying to move ARC over to generic word-at-a-time
interface.

 - 1/4 is a trivial fix (and needed for ARC switch)
 - 2/4 is mucking with internals hence the RFC. I could very likely be
   overlooking some possible DoS / exploit issues and apologies in advance
   if thats the case but I felt like sharing it anyways to see what
   others think.
 - 3/4, 4/4 are ARC changes to remove the existing ARC version and
   switch to generic (needs 1/4).

Thx,
-Vineet

Vineet Gupta (4):
  asm-generic/uaccess: don't define inline functions if noinline lib/*
    in use
  lib/strncpy_from_user: Remove redundant user space pointer range check
  ARC: uaccess: remove noinline variants of __strncpy_from_user() and
    friends
  ARC: uaccess: use optimized generic __strnlen_user/__strncpy_from_user

 arch/arc/Kconfig                      |  2 +
 arch/arc/include/asm/Kbuild           |  1 -
 arch/arc/include/asm/uaccess.h        | 87 ++-------------------------
 arch/arc/include/asm/word-at-a-time.h | 49 +++++++++++++++
 arch/arc/mm/extable.c                 | 23 -------
 include/asm-generic/uaccess.h         |  4 ++
 lib/strncpy_from_user.c               | 36 ++++-------
 lib/strnlen_user.c                    | 28 +++------
 8 files changed, 79 insertions(+), 151 deletions(-)
 create mode 100644 arch/arc/include/asm/word-at-a-time.h

-- 
2.20.1