[Pkg-libvirt-maintainers] Bug#930929: libvirt: is no longer able to use kvm

[Raphaël Hertzog]

Source: libvirt
Version: 5.0.0-4
Severity: serious

For a few days/weeks (I'm not sure when it started exactly), I can no
longer run my VM with virt-manager.

On startup of libvirtd I have many messages like this one (one for each VM
I guess):
libvirtd[8281]: invalid argument: could not find capabilities for arch=x86_64 domaintype=kvm 

When I try to start a VM I see this in the logs of libvirtd:
libvirtd[12569]: Unable to read from monitor: Connexion ré-initialisée par le correspondant
libvirtd[12569]: internal error: qemu unexpectedly closed the monitor: Could not access KVM kernel module: Permission denied
                 2019-06-22T17:07:23.635870Z qemu-system-x86_64: failed to initialize KVM: Permission denied
libvirtd[12569]: internal error: process exited while connecting to monitor: Could not access KVM kernel module: Permission denied
                 2019-06-22T17:07:23.635870Z qemu-system-x86_64: failed to initialize KVM: Permission denied

But I do have /dev/kvm and I have hardware virtualization enabled in the
BIOS.

$ ls -al /dev/kvm
crw-rw----+ 1 root root 10, 232 juin  22 19:07 /dev/kvm
$ getfacl /dev/kvm
# file: dev/kvm
# owner: root
# group: root
user::rw-
user:rhertzog:rw-
group::---
mask::rw-
other::---

And I do have the required kernel modules:
$ lsmod|grep kvm
kvm_intel             245760  0
kvm                   724992  1 kvm_intel
irqbypass              16384  1 kvm

I also have qemu-kvm installed:
$ dpkg -l qemu*|grep ^ii
ii  qemu-kvm           1:3.1+dfsg-8 amd64        QEMU Full virtualization on x86 hardware
ii  qemu-system-common 1:3.1+dfsg-8 amd64        QEMU full system emulation binaries (common files)
ii  qemu-system-data   1:3.1+dfsg-8 all          QEMU full system emulation (data files)
ii  qemu-system-gui    1:3.1+dfsg-8 amd64        QEMU full system emulation binaries (user interface and audio support)
ii  qemu-system-x86    1:3.1+dfsg-8 amd64        QEMU full system emulation binaries (x86)
ii  qemu-user          1:3.1+dfsg-8 amd64        QEMU user mode emulation binaries
ii  qemu-user-static   1:3.1+dfsg-8 amd64        QEMU user mode emulation binaries (static version)
ii  qemu-utils         1:3.1+dfsg-8 amd64        QEMU utilities

I removed virtualbox and rebooted to make sure it's not a bad interaction but it did not help.
I don't know what else I should look into.

-- System Information:
Debian Release: 10.0
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (500, 'stable'), (500, 'oldstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.19.0-5-amd64 (SMP w/4 CPU cores)
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8), LANGUAGE=fr_FR.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled