sys_personality: remove the bogus checks in sys_personality()->__set_personality...
commit2ee7c922f20c96dba56fd378a466790d87f42e84
authorOleg Nesterov <oleg@redhat.com>
Tue, 10 Aug 2010 00:20:30 +0000 (9 17:20 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 10 Aug 2010 03:45:05 +0000 (9 20:45 -0700)
tree9eda39ff1867c4695c1e7349045ccc23176b623b
parent5bf1d290b57e392eaf4bfb15c67f315fce4140be
sys_personality: remove the bogus checks in sys_personality()->__set_personality() path

Cleanup, no functional changes.

- __set_personality() always changes ->exec_domain/personality, the
  special case when ->exec_domain remains the same buys nothing but
  complicates the code. Unify both cases to simplify the code.

- The -EINVAL check in sys_personality() was never right. If we assume
  that set_personality() can fail we should check the value it returns
  instead of verifying that task->personality was actually changed.

  Remove it. Before the previous patch it was possible to hit this case
  due to overflow problems, but this -EINVAL just indicated the kernel
  bug.

OTOH, probably it makes sense to change lookup_exec_domain() to return
ERR_PTR() instead of default_exec_domain if the search in exec_domains
list fails, and report this error to the user-space.  But this means
another user-space change, and we have in-kernel users which need fixes.
For example, PER_OSF4 falls into PER_MASK for unkown reason and nobody
cares to register this domain.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Wenming Zhang <wezhang@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/exec_domain.c