*** This bug is a duplicate of bug 1778854 *** https://bugs.launchpad.net/bugs/1778854
Public bug reported: Hi, I have run into this and I'm not entirely sure if it is an error or just not supported. I'll file the bug and would ask for a check and answer by the kernel Team and IBM about it. On power you can never load the usual kvm_hv module in a guest. $ sudo modprobe kvm_hv modprobe: ERROR: could not insert 'kvm_hv': No such device That is normal and expected. But on a Power9 system I can neither load kvm_pr which was usually the way to go for nested KVM. $ sudo modprobe kvm_pr modprobe: ERROR: could not insert 'kvm_pr': Input/output error There is no error whatsoever in dmesg when triggering this. >From libvirt the guest is defined with all defaults - see >http://paste.ubuntu.com/p/2r34SG6pq6/ That gives the guest CPU this guest view: cat /proc/cpuinfo processor : 0 cpu : POWER9 (architected), altivec supported clock : 2134.000000MHz revision : 2.2 (pvr 004e 1202) timebase : 512000000 platform : pSeries model : IBM pSeries (emulated by qemu) machine : CHRP IBM pSeries (emulated by qemu) MMU : Radix Nothing obvious here, also the module exists and seems normal to me: $ modinfo kvm_pr filename: /lib/modules/4.17.0-6-generic/kernel/arch/powerpc/kvm/kvm-pr.ko alias: devname:kvm alias: char-major-10-232 license: GPL srcversion: 2472883ADEEBC51508B6BF4 depends: kvm intree: Y name: kvm_pr vermagic: 4.17.0-6-generic SMP mod_unload mprofile-kernel relocatable sig_id: PKCS#7 signer: sig_key: sig_hashalgo: md4 signature: 30:82... Current kernel is From Cosmic (as that is what I test for atm): 4.17.0-6-generic If I start the guest with the "least virtual" cpu via <cpu mode='host-passthrough' check='none'/> I get no difference in /proc/cpuinfo from the guest nor does the problem change. So is there a special constraint to Power9, is it the cosmic kernel, something else - would be great if there would be some advice on this. ** Affects: linux (Ubuntu) Importance: Undecided Status: New -- 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/1786740 Title: kvm_pr can't load on power9 Status in linux package in Ubuntu: New Bug description: Hi, I have run into this and I'm not entirely sure if it is an error or just not supported. I'll file the bug and would ask for a check and answer by the kernel Team and IBM about it. On power you can never load the usual kvm_hv module in a guest. $ sudo modprobe kvm_hv modprobe: ERROR: could not insert 'kvm_hv': No such device That is normal and expected. But on a Power9 system I can neither load kvm_pr which was usually the way to go for nested KVM. $ sudo modprobe kvm_pr modprobe: ERROR: could not insert 'kvm_pr': Input/output error There is no error whatsoever in dmesg when triggering this. From libvirt the guest is defined with all defaults - see http://paste.ubuntu.com/p/2r34SG6pq6/ That gives the guest CPU this guest view: cat /proc/cpuinfo processor : 0 cpu : POWER9 (architected), altivec supported clock : 2134.000000MHz revision : 2.2 (pvr 004e 1202) timebase : 512000000 platform : pSeries model : IBM pSeries (emulated by qemu) machine : CHRP IBM pSeries (emulated by qemu) MMU : Radix Nothing obvious here, also the module exists and seems normal to me: $ modinfo kvm_pr filename: /lib/modules/4.17.0-6-generic/kernel/arch/powerpc/kvm/kvm-pr.ko alias: devname:kvm alias: char-major-10-232 license: GPL srcversion: 2472883ADEEBC51508B6BF4 depends: kvm intree: Y name: kvm_pr vermagic: 4.17.0-6-generic SMP mod_unload mprofile-kernel relocatable sig_id: PKCS#7 signer: sig_key: sig_hashalgo: md4 signature: 30:82... Current kernel is From Cosmic (as that is what I test for atm): 4.17.0-6-generic If I start the guest with the "least virtual" cpu via <cpu mode='host-passthrough' check='none'/> I get no difference in /proc/cpuinfo from the guest nor does the problem change. So is there a special constraint to Power9, is it the cosmic kernel, something else - would be great if there would be some advice on this. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1786740/+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