On Wed, 2018-03-28 at 07:41 -0400, okaya@codeaurora.org wrote:

Yes, we want to get there indeed. It is because of some arch not 
implementing writel properly. Maintainers want to play safe.

That is why I asked if IA64 and other well known archs follow the 
strongly ordered rule at this moment like PPC and ARM.

Or should we go and inform every arch about this before yanking wmb()?

Maintainers are afraid of introducing a regression.

Let's fix all archs, it's way easier than fixing all drivers. Half of
the archs are unused or dead anyway.

quoted

The above code makes no sense, and just looks stupid to me. It also
generates pointlessly bad code on x86, so it's bad there too.

                Linus