Not this exact problem but one with similar symptoms. From kernel 3.5 onwards there was a problem with guests not receiving RTC ticks which was reported here - http://lists.gnu.org/archive/html/qemu- devel/2013-02/msg03827.html
The 3.2 kernel from 12.04.1 never had any issues but the 3.5 kernel from 12.04.2 onwards hit the RTC bug whoch was fixed in later releases of QEMU. -- You received this bug notification because you are a member of Ubuntu Server Team, which is subscribed to qemu in Ubuntu. https://bugs.launchpad.net/bugs/1322441 Title: QEMU Windows guest unstable after random amount of time To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/1322441/+subscriptions -- Ubuntu-server-bugs mailing list Ubuntu-server-bugs@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-server-bugs