Yidong Ren <Yidong.Ren@xxxxxxxxxxxxx> writes: >> From: Yidong Ren <yidren@xxxxxxxxxxxxxxxxx> >> Sent: Monday, July 23, 2018 6:26 PM >> + pcpu_sum = kvmalloc(sizeof(struct netvsc_ethtool_pcpu_stats) * >> + num_present_cpus(), GFP_KERNEL); > > Since there is no plan for CPU hotplug in Hyper-V in short term, it is fine > to use num_present_cpus for now. We can move to debugfs later if necessary. While you do for_each_present_cpu() in netvsc_get_ethtool_stats(), netvsc_get_pcpu_stats() does for_each_possible_cpu(). This looks inconsistent. The allocation you're doing here is short-lived so I would suggest you use possible_cpus everywhere. Even knowing there's no CPU hotplug on Hyper-V at this moment, it can appear later and we'll get a hard-to-find issue. Moreover, we may consider using netvsc driver on e.g. KVM with Hyper-V enlightenments and KVM has CPU hotplug already. -- Vitaly _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
