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> > > > > > + /* > > > + * A combined IRQ might call into this function with the queue disabled. > > > + * E.g. kdump, where stale HW PROD vs SW CONS would drive a bogus drain > > > + * and a CONS write to a disabled queue. > > > + */ > > > + if (!(readl_relaxed(smmu->base + ARM_SMMU_CR0) & CR0_EVTQEN)) > > > + return IRQ_NONE; > > > > I don't think we should be doing register reads on these paths. > > > > Why not load a different irq function instead? > > Yea. Perhaps we could even entirely skip their IRQ requests. Only > gerror should be kept in kdump case. Yeah, if the irq handlers don't do anything then don't register them makes alot of sense.. Jason