Hi Andrew,

After merging the akpm-current tree, today's linux-next build (powerpc
ppc64_defconfig) failed like this:

In file included from include/linux/init.h:4:0,
                 from fs/eventpoll.c:14:
fs/eventpoll.c: In function 'eventpoll_init':
include/linux/compiler.h:321:20: error: call to '__compiletime_assert_2137' declared with attribute error: BUILD_BUG_ON failed: sizeof(void *) <= 8 && sizeof(struct epitem) > 128
    prefix ## suffix();    \
                    ^
include/linux/compiler.h:326:2: note: in expansion of macro '__compiletime_assert'
  __compiletime_assert(condition, msg, prefix, suffix)
  ^
include/linux/compiler.h:338:2: note: in expansion of macro '_compiletime_assert'
  _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
  ^
include/linux/bug.h:50:37: note: in expansion of macro 'compiletime_assert'
 #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
                                     ^
include/linux/bug.h:74:2: note: in expansion of macro 'BUILD_BUG_ON_MSG'
  BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
  ^
fs/eventpoll.c:2137:2: note: in expansion of macro 'BUILD_BUG_ON'
  BUILD_BUG_ON(sizeof(void *) <= 8 && sizeof(struct epitem) > 128);
  ^

Presumably caused by commit 83b5ec605b7e ("epoll: optimize EPOLL_CTL_DEL
using rcu").

I have reverted that commit and 2 follow up commits to that file ("epoll:
do not take global 'epmutex' for simple topologies" and
"epoll-do-not-take-global-epmutex-for-simple-topologies-fix") for today.

-- 
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au