mirror of
https://github.com/GNS3/gns3-server.git
synced 2026-10-30 12:12:21 +02:00
53164eccee
When the compute is itself a Hyper-V guest without an invariant TSC (e.g. the GNS3 VM on hosts whose CPU lacks TSC scaling), Linux falls back to the hyperv_clocksource_tsc_page clocksource and the guest timekeeping KVM derives from the TSC is broken with recent kernels: - kvmclock runs thousands of times too fast: Linux guests (MikroTik RouterOS, ...) panic with "watchdog: BUG: soft lockup - CPU#0 stuck for 29604s" and reboot in a loop right after boot; - TSC deadline timers fire far too late: guests with -cpu host hang. The only workaround so far was -machine accel=tcg, i.e. no KVM at all. Add a kvmclock setting to the [Qemu] section (auto, enabled, disabled). In auto mode, KVM guests started on a host whose clocksource is a Hyper-V one get kvmclock and tsc-deadline turned off: on the -cpu given in the additional options (unless it sets these features itself), otherwise on QEMU's default CPU model. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>