Hi Dave, Eric, during heavy network load we turn off/on cpus. Sometimes this causes a stall on the network device. Digging into the dump I found out following: napi is scheduled but does not run. From the I/O buffers and the napi state I see napi/rx_softirq processing has stopped because the budget was reached. napi stays in the softnet_data poll_list and the rx_softirq was raised again. I assume at this time the cpu offline comes in. the rx softirq is raised/moved to another cpu but napi stays in the poll_list of the softnet_data of the now offline cpu. reviewing dev_cpu_callback (net/core/dev.c) I did not find the poll_list is transfered to the new cpu. Do you think this could cause the stall or did I miss something? Thx for your help. Frank -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html