lkml.org 
[lkml]   [2016]   [Oct]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 07/13] futex: Throughput-optimized (TP) futexes
On Fri, 30 Sep 2016, Waiman Long wrote:
> + WRITE_ONCE(state->owner, current);
> + preempt_disable();
> + for (;;) {
> + ret = futex_trylock(uaddr, vpid, &uval, true);

Did you actually read what I said? You CANNOT access userspace in a preempt
disabled region without disabling pagefaults and handle the resulting
wreckage yourself.

End of review.

tglx

\
 
 \ /
  Last update: 2016-10-01 08:51    [W:0.085 / U:1.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site