On Tue, Dec 05, 2017 at 08:31:20PM +0200, Michael S. Tsirkin wrote: > Apropos, READ_ONCE is now asymmetrical with WRITE_ONCE. > > I can read a pointer with READ_ONCE and be sure the value > is sane, but only if I also remember to put in smp_wmb before > WRITE_ONCE. Otherwise the pointer is ok but no guarantees > about the data pointed to. That was already the case on everything except Alpha. And the canonical match do the data dependency is store_release, not wmb.
