[1877] sci: load kvm modules via modules-load.d to fix libvirtd boot race#188
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libvirtd's Cloud Hypervisor driver does a one-time /dev/kvm existence check at init (ch_conf.c). If /dev/kvm doesn't exist at that moment the driver is permanently skipped with no retry. kvm_amd/kvm_intel are loaded by udev (non-deterministic), not by systemd-modules-load.service (which runs Before=sysinit.target). This creates a race: libvirtd can start before /dev/kvm is created. Adding kvm.conf to modules-load.d moves loading to systemd-modules-load.service, which is guaranteed to complete before libvirtd starts (via the sysinit.target -> multi-user.target chain). The arch-mismatched module fails harmlessly with -EOPNOTSUPP. Fixes intermittent CI failures in Test CloudHypervisor jobs.
anokfireball
changed the title
fwiesel
approved these changes
Mar 5, 2026
joker-at-work
approved these changes
Mar 5, 2026
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libvirtd's Cloud Hypervisor driver does a one-time /dev/kvm existence check at init (ch_conf.c). If /dev/kvm doesn't exist at that moment the driver is permanently skipped with no retry.
kvm_amd/kvm_intel are loaded by udev (non-deterministic), not by systemd-modules-load.service (which runs Before=sysinit.target). This creates a race: libvirtd can start before /dev/kvm is created.
Adding kvm.conf to modules-load.d moves loading to systemd-modules-load.service, which is guaranteed to complete before libvirtd starts (via the sysinit.target -> multi-user.target chain). The arch-mismatched module fails harmlessly with -EOPNOTSUPP.
Fixes intermittent CI failures in Test CloudHypervisor jobs.