On Mon, Nov 29 2021 at 13:52, Thomas Gleixner wrote: > On Mon, Nov 29 2021 at 10:55, Will Deacon wrote: >> On Sat, Nov 27, 2021 at 02:20:59AM +0100, Thomas Gleixner wrote: >>> + smmu->evtq.q.irq = msi_get_virq(dev, EVTQ_MSI_INDEX); >>> + smmu->gerr_irq = msi_get_virq(dev, GERROR_MSI_INDEX); >>> + smmu->priq.q.irq = msi_get_virq(dev, PRIQ_MSI_INDEX); >> >> Prviously, if retrieval of the MSI failed then we'd fall back to wired >> interrupts. Now, I think we'll clobber the interrupt with 0 instead. Can >> we make the assignments to smmu->*irq here conditional on the MSI being >> valid, please? > > So the wired irq number is in ->irq already and MSI does an override > if available. Not really obvious... But, this happens right after: ret = platform_msi_domain_alloc_irqs(dev, nvec, arm_smmu_write_msi_msg); So if that succeeded then the descriptors exist and have interrupts assigned. Thanks, tglx