Re: [PATCH] powerpc/pseries: unregister VPA when hot unplugging a CPU

2022-12-08 Thread Michael Ellerman
On Mon, 14 Nov 2022 17:01:50 +0100, Laurent Dufour wrote: > The VPA should unregister when offlining a CPU. Otherwise there could be a > short window where 2 CPUs could share the same VPA. > > This happens because the hypervisor is still keeping the VPA attached to > the vCPU even if it became off

Re: [PATCH] powerpc/pseries: unregister VPA when hot unplugging a CPU

2022-11-18 Thread Nathan Lynch
Laurent Dufour writes: > The VPA should unregister when offlining a CPU. Otherwise there could be a > short window where 2 CPUs could share the same VPA. > > This happens because the hypervisor is still keeping the VPA attached to > the vCPU even if it became offline. > > Here is a potential situ

[PATCH] powerpc/pseries: unregister VPA when hot unplugging a CPU

2022-11-14 Thread Laurent Dufour
The VPA should unregister when offlining a CPU. Otherwise there could be a short window where 2 CPUs could share the same VPA. This happens because the hypervisor is still keeping the VPA attached to the vCPU even if it became offline. Here is a potential situation: 1. remove proc A, 2. add pro