Add memory barrier when waiting on futex

2013-11-25 Thread Ma, Xindong
We encountered following panic several times: [ 74.671982] BUG: unable to handle kernel NULL pointer dereference at 0008 [ 74.672101] IP: [] wake_futex+0x47/0x80 [ 74.672185] *pdpt = 10108001 *pde = [ 74.672278] Oops: 0002 [#1] PREEMPT SMP [ 74.672403] Modul

RE: Add memory barrier when waiting on futex

2013-11-25 Thread Ma, Xindong
> -Original Message- > From: Peter Zijlstra [mailto:pet...@infradead.org] > Sent: Monday, November 25, 2013 10:40 PM > To: Ma, Xindong > Cc: stable@vger.kernel.org; stable-comm...@vger.kernel.org; Wysocki, Rafael J; > ccr...@google.com; t...@linutronix.de; dvh...@lin

RE: Add memory barrier when waiting on futex

2013-11-26 Thread Ma, Xindong
> -Original Message- > From: Peter Zijlstra [mailto:pet...@infradead.org] > Sent: Tuesday, November 26, 2013 4:26 PM > To: Ma, Xindong > Cc: stable@vger.kernel.org; stable-comm...@vger.kernel.org; Wysocki, Rafael > J; ccr...@google.com; t...@linutronix.de; dvh...@lin