Re: [RFC] Deadlock via recursive wakeup via RCU with threadirqs

Andrea Parri
2019-06-29T15:12:52Z

Hi Steve,

> As Paul stated, interrupts are synchronization points. Archs can only
> play games with ordering when dealing with entities outside the CPU
> (devices and other CPUs). But if you have assembly that has two stores,
> and an interrupt comes in, the arch must guarantee that the stores are
> done in that order as the interrupt sees it.

Hopefully I'm not derailing the conversation too much with my questions
... but I was wondering if we had any documentation (or inline comments)
elaborating on this "interrupts are synchronization points"?

Thanks,
Andrea