On Tue, 2016-09-20 at 07:11 -0700, Eric Dumazet wrote: > On Tue, 2016-09-20 at 15:39 +0200, Jiri Pirko wrote: > > > I see. So how to silent the warning? > > > > We can replace the atomic_add_return() and use a loop around > atomic_read() and atomic_cmpxhg() > > This would change the nice property of x86 xadd into a loop. > > Or we also could fallback to random generation if the atomic_cmpxchg() > fails. > > I'll provide a patch, thanks. >
I looks at other places, I am surprised you do not see other UBSAN issues in networking :) netdev_refcnt_read() can potentially gives errors as well.
