------- Comment From mete.du...@ibm.com 2024-09-12 07:23 EDT------- Hi, any outlook on this issue?
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/2078347 Title: [UBUNTU 24.04] Udev/rules: Missing rules causes newly added CPUs to stay offline Status in linux package in Ubuntu: New Bug description: ---Problem Description---------------------------------------------------------------------------------- Adding a configured CPU to a system (LPAR, ZVM or KVM) leaves that CPU configured but hotplugged off. # lscpu -e CPU NODE DRAWER BOOK SOCKET CORE L1d:L1i:L2 ONLINE CONFIGURED POLARIZATION ADDRESS 0 0 0 0 0 0 0:0:0 yes yes horizontal 0 1 0 0 0 1 1 1:1:1 yes yes horizontal 1 2 0 0 0 2 2 2:2:2 yes yes horizontal 2 3 0 0 0 3 3 3:3:3 yes yes horizontal 3 4 0 0 0 4 4 4:4:4 yes yes horizontal 4 5 0 0 0 5 5 5:5:5 yes yes horizontal 5 6 - - - - - - no yes horizontal 6 7 - - - - - - no yes horizontal 7 ---Debugger--- A debugger is not configured Machine Type = z/VM, LPAR ---uname output--- 6.8.0-41-generic #41-Ubuntu SMP Fri Aug 2 19:51:49 UTC 2024 s390x s390x s390x GNU/Linux ---Steps to Reproduce--- Easiest way to reproduce is using a KVM guest to add new CPUs. 1. Before adding CPUs: $ virsh dumpxml vm <domain type='kvm' id='106'> ... <vcpu placement='static' current='6'>8</vcpu> <vcpus> <vcpu id='0' enabled='yes' hotpluggable='no' order='1'/> <vcpu id='1' enabled='yes' hotpluggable='no' order='2'/> <vcpu id='2' enabled='yes' hotpluggable='yes' order='3'/> <vcpu id='3' enabled='yes' hotpluggable='yes' order='4'/> <vcpu id='4' enabled='yes' hotpluggable='yes' order='5'/> <vcpu id='5' enabled='yes' hotpluggable='yes' order='6'/> <vcpu id='6' enabled='no' hotpluggable='yes'/> <vcpu id='7' enabled='no' hotpluggable='yes'/> 2. Attempt to add CPUs to the guest in a "running" state. $ virsh setvcpus vm 8 --live 3. The guest XML is updated : ... <vcpu placement='static'>8</vcpu> <vcpus> <vcpu id='0' enabled='yes' hotpluggable='no' order='1'/> <vcpu id='1' enabled='yes' hotpluggable='no' order='2'/> <vcpu id='2' enabled='yes' hotpluggable='yes' order='3'/> <vcpu id='3' enabled='yes' hotpluggable='yes' order='4'/> <vcpu id='4' enabled='yes' hotpluggable='yes' order='5'/> <vcpu id='5' enabled='yes' hotpluggable='yes' order='6'/> <vcpu id='6' enabled='yes' hotpluggable='yes' order='7'/> <vcpu id='7' enabled='yes' hotpluggable='yes' order='8'/> </vcpus> 4. But inside the guest, the CPUs are in offline state: $ lscpu -e CPU NODE DRAWER BOOK SOCKET CORE L1d:L1i:L2 ONLINE CONFIGURED POLARIZATION ADDRESS 0 0 0 0 0 0 0:0:0 yes yes horizontal 0 1 0 0 0 1 1 1:1:1 yes yes horizontal 1 2 0 0 0 2 2 2:2:2 yes yes horizontal 2 3 0 0 0 3 3 3:3:3 yes yes horizontal 3 4 0 0 0 4 4 4:4:4 yes yes horizontal 4 5 0 0 0 5 5 5:5:5 yes yes horizontal 5 6 - - - - - - no yes horizontal 6 7 - - - - - - no yes horizontal 7 5. Post rebooting the guest, the CPUs are online: $ virsh reboot vm Inside the guest: $ lscpu -e CPU NODE DRAWER BOOK SOCKET CORE L1d:L1i:L2 ONLINE CONFIGURED POLARIZATION ADDRESS 0 0 0 0 0 0 0:0:0 yes yes horizontal 0 1 0 0 0 1 1 1:1:1 yes yes horizontal 1 2 0 0 0 2 2 2:2:2 yes yes horizontal 2 3 0 0 0 3 3 3:3:3 yes yes horizontal 3 4 0 0 0 4 4 4:4:4 yes yes horizontal 4 5 0 0 0 5 5 5:5:5 yes yes horizontal 5 6 0 0 0 6 6 6:6:6 yes yes horizontal 6 7 0 0 0 7 7 7:7:7 yes yes horizontal 7 The CPUs should be online after adding them to the system. Other distros already have a udev rule to circumvent this under; /etc/udev/rules.d/ The rule does a check if a newly added CPUs are configured but not online, then hotplugs it to make it online. If CPUs are NOT configured then they should stay offline. Contact Information = mete.du...@ibm.com To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2078347/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
