acct_exit_ns --> acct_file_reopen deletes timer without check timer
execution on other CPUs.  So acct_timeout() can change an unmapped memory.
Signed-off-by: NVitaliy Gusev <vgusev@openvz.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>