On 10/11/20 18:52, Luck, Tony wrote:
Look at what it is trying to do ... change the behavior of the platform w.r.t. logging of memory errors. How does that make any sense for a guest ...
Logging of memory errors certainly makes sense for a guest, KVM already does MCE forwarding as you probably know.
The exact set of information that MSR_ERROR_CONTROL[1] adds may not make much sense in the case of KVM, but it may make sense for other hypervisors that do nothing but partition the host. (Difficult for me to say since the relevant part of the SDM might as well be written in Klingon :)).
In any case, checking HYPERVISOR is not enough because having it clear is a valid configuration. So you would still have to switch to {rd,wr}msrl_safe, and then checking HYPERVISOR is pointless.
Paolo
that doesn't even know what memory is present on the platform. Or have guarantees that what it sees as memory address 0x12345678 maps to the same set of cells in a DRAM from one second to the next?
