On 2020-12-09 11:05:45 [+0100], Peter Zijlstra wrote: > In general we have the rule that as long as a lock is only ever used > from task context (like the above ilb->lock, afaict) then it doesn't > matter if you also take it with (soft)irqs disabled or not. But this > softirq scheme breaks that. If you ever take a lock with BH disabled, > you must now always take it with BH disabled, otherwise you risk > deadlocks against the softirq_ctrl lock. > > Or am I missing something obvious (again) ? No. With this explanation it makes sense. Thank you. Sebastian
