On 08.08.2024 15:19, Marek Marczykowski-Górecki wrote:
> On Thu, Aug 08, 2024 at 01:22:30PM +0200, Jan Beulich wrote:
>> x86/x2APIC: correct cluster tracking upon CPUs going down for S3
>>
>> Downing CPUs for S3 is somewhat special: Since we can expect the system
>> to come back up in exactly the same hardware configuration, per-CPU data
>> for the secondary CPUs isn't de-allocated (and then cleared upon re-
>> allocation when the CPUs are being brought back up). Therefore the
>> cluster_cpus per-CPU pointer will retain its value for all CPUs other
>> than the final one in a cluster (i.e. in particular for all CPUs in the
>> same cluster as CPU0). That, however, is in conflict with the assertion
>> early in init_apic_ldr_x2apic_cluster().
>>
>> Note that the issue is avoided on Intel hardware, where we park CPUs
>> instead of bringing them down.
> 
> I wonder why I don't hit this issue on baremetal AMD, only on nested.

Different clustering arrangements?

> Anyway,
> 
> Tested-by: Marek Marczykowski-Górecki <[email protected]>

Great, thanks.

Jan

Reply via email to