On Thu, 13 Feb 2025 21:38:12 +0100 Frederic Weisbecker wrote: > > > Just to make sure I follow the netpoll issue. What would you like to fix > > > in netpoll exactly? > > > > Nothing in netpoll, the problem is that netdevsim calls napi_schedule > > from the xmit path. That's incompatible with netpoll. We should fix > > netdevsim instead (unless more real drivers need napi-from-xmit to > > work). > > Let me clarify, because I don't know much this area. If the problem is that xmit > can't call napi_schedule() by design, then I defer to you. But if the problem is that > napi_schedule() may or may not be called from an interrupt, please note that > local_bh_enable() won't run softirqs from a hardirq and will instead defer to > IRQ tail. So it's fine to do an unconditional pair of local_bh_disable() / local_bh_enable(). I don't know where this is in the code TBH, but my understanding is that HW IRQs - yes, as you say it'd be safe; the problem is that we have local_irq_save() all over the place. And that is neither protected from local_bh_enable(), not does irq_restore execute softirqs.
