Re: [patch 4/8] futex: Add support for unlocking robust futexes

[Thomas Gleixner]

On Wed, Mar 18 2026 at 15:47, Peter Zijlstra wrote:
> On Wed, Mar 18, 2026 at 09:02:01AM +0100, Peter Zijlstra wrote:
>> So I think we once tried to determine if syscall could be considered to
>> imply memory ordering, and I think the take-away at the time was that we
>> could not assume so.
>> 
>> But its been a long time, maybe I misremember.
>
> Ah, it was for the sys_membarrier() thing. And yes, a syscall itself
> does not imply memory ordering for all architectures. And since this
> very much needs release semantics, it is best to be explicit about that.

What a mess...