Re: [PATCH v10 6/6] x86/split_lock: Enable split lock detection by kernel parameter

[Andy Lutomirski]

> On Nov 21, 2019, at 2:29 PM, Luck, Tony <tony.luck@xxxxxxxxx> wrote:
> 
> ï
>> 
>> It would be really, really nice if we could pass this feature through to a VM. Can we?
> 
> It's hard because the MSR is core scoped rather than thread scoped.  So on an HT
> enabled system a pair of logical processors gets enabled/disabled together.
> 
> 

Well that sucks.

Could we pass it through if the host has no HT?  Debugging is *so* much easier in a VM.  And HT is a bit dubious these days anyway.