On Fri, 19 Apr 2024 12:17:01 -0400 boris.ostrovsky@xxxxxxxxxx wrote: > On 4/17/24 9:58 AM, boris.ostrovsky@xxxxxxxxxx wrote: > > > > I noticed that I was using a few months old qemu bits and now I am > > having trouble reproducing this on latest bits. Let me see if I can get > > this to fail with latest first and then try to trace why the processor > > is in this unexpected state. > > Looks like 012b170173bc "system/qdev-monitor: move drain_call_rcu call > under if (!dev) in qmp_device_add()" is what makes the test to stop failing. > > I need to understand whether lack of failures is a side effect of timing > changes that simply make hotplug fail less likely or if this is an > actual (but seemingly unintentional) fix. Agreed, we should find out culprit of the problem. PS: also if you are using AMD host, there was a regression in OVMF where where vCPU that OSPM was already online-ing, was yanked from under OSMP feet by OVMF (which depending on timing could manifest as lost SIPI). edk2 commit that should fix it is: https://github.com/tianocore/edk2/commit/1c19ccd5103b Switching to Intel host should rule that out at least. (or use fixed edk2-ovmf-20240524-5.el10.noarch package from centos, if you are forced to use AMD host) > -boris >