On 10/09/2014 07:12 PM, Tadeusz Struk wrote: > On 10/09/2014 02:42 PM, Prarit Bhargava wrote: >>>> I don't think cpu hotplug matters here. This is one (probe) time >>>> determination if the configuration is optimal or not and if it makes >>>> sense to use this accelerator or not. >> It absolutely matters. num_online_cpus() *changes* depending on the # of cpus. > > Sure, but I still think that we are safe here. > No, you're not. Dropping a single CPU changes num_online_cpus(), which results in static uint8_t adf_get_dev_node_id(struct pci_dev *pdev) { unsigned int bus_per_cpu = 0; struct cpuinfo_x86 *c = &cpu_data(num_online_cpus() - 1); <<< this being different. if (!c->phys_proc_id) return 0; bus_per_cpu = 256 / (c->phys_proc_id + 1); <<< this being different if (bus_per_cpu != 0) return pdev->bus->number / bus_per_cpu; <<< and this being different return 0; } P. -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html