On Fri, Apr 21 2023 at 18:09, Sebastian Andrzej Siewior wrote: > On 2023-04-21 17:30:24 [+0200], Thomas Gleixner wrote: >> >> > The out-of-tree RT patches make extensive use of the code. Since it is >> >> > upstream code, I assumed it should go via the official stable trees. >> >> > Without RT, the code is limited the rt_mutex_lock() used by I2C and the >> >> > RCU booster-mutex. >> >> >> >> Which is a reason to route it through the upstream stable trees, no? >> > >> > I do not understand. Why would we take a patch in the stable tree >> > because an out-of-tree change requires it? >> >> The change is to the rtmutex core which _IS_ used in tree by futex, RCU >> and some drivers. > > not back stab but to clarify: futex does not use the annotation (it does > not use the fastpath) but RCU-boosting _and_ I2C-bus code does use it. Futex requires it too, really. The patch is about the slowpath, no?
