Messages in this thread | | | Date | Mon, 27 Oct 2014 11:20:35 +0800 | From | Ren Qiaowei <> | Subject | Re: [PATCH v9 05/12] x86, mpx: on-demand kernel allocation of bounds tables |
| |
On 10/24/2014 08:08 PM, Thomas Gleixner wrote: > On Sun, 12 Oct 2014, Qiaowei Ren wrote: >> + /* >> + * Go poke the address of the new bounds table in to the >> + * bounds directory entry out in userspace memory. Note: >> + * we may race with another CPU instantiating the same table. >> + * In that case the cmpxchg will see an unexpected >> + * 'actual_old_val'. >> + */ >> + ret = user_atomic_cmpxchg_inatomic(&actual_old_val, bd_entry, >> + expected_old_val, bt_addr); > > This is fully preemptible non-atomic context, right? > > So this wants a proper comment, why using > user_atomic_cmpxchg_inatomic() is the right thing to do here. >
Well, we will address it.
Thanks, Qiaowei
| |