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McKenney wrote: > On Fri, Jul 11, 2025 at 10:05:26AM -0700, Paul E. McKenney wrote: >> On Fri, Jul 11, 2025 at 09:46:25AM -0400, Mathieu Desnoyers wrote: > > [ . . . ] > >>> AFAIU the goal here is to turn the guard(preempt_notrace)() into a >>> guard(rcu_notrace)() because the preempt-off critical sections don't >>> agree with BPF. >> >> OK, got it, thank you! >> >> The combination of BPF and CONFIG_PREEMPT_RT certainly has provided at >> least its share of entertainment, that is for sure. ;-) > > Is there a similar issue with CONFIG_PREEMPT_LAZY, given that in that > case rcu_read_unlock() maps to preempt_enable(), which also can invoke > the scheduler? I'll have to defer that question to someone who is more familiar than me with the internals of CONFIG_PREEMPT_LAZY. Thanks for your vote of confidence though! ;-) Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com