Dexuan, On Mon, Jul 19 2021 at 20:33, Dexuan Cui wrote: > This is a bare metal x86-64 host with Intel CPUs. Yes, I believe the > issue is in the IOMMU Interrupt Remapping mechanism rather in the > NIC driver. I just don't understand why bringing the CPUs online and > offline can work around the issue. I'm trying to dump the IOMMU IR > table entries to look for any error. can you please enable GENERIC_IRQ_DEBUGFS and provide the output of cat /sys/kernel/debug/irq/irqs/$THENICIRQS Thanks, tglx