Re: [PATCH v2 0/6] Introduce KVM_{GET|SET}_SREGS2 and fix PDPTR migration

[Sean Christopherson <seanjc@google.com>]

On Mon, Apr 26, 2021, Maxim Levitsky wrote:
> This patch set aims to fix few flaws that were discovered
> in KVM_{GET|SET}_SREGS on x86:
> 
> * There is no support for reading/writing PDPTRs although
>   these are considered to be part of the guest state.
> 
> * There is useless interrupt bitmap which isn't needed
> 
> * No support for future extensions (via flags and such)
> 
> Also if the user doesn't use the new SREG2 api, the PDPTR
> load after migration is now done on KVM_REQ_GET_NESTED_STATE_PAGES
> to at least read them correctly in cases when guest memory
> map is not up to date when nested state is loaded.
> 
> This patch series was tested by doing nested migration test
> of 32 bit PAE L1 + 32 bit PAE L2 on AMD and Intel and by
> nested migration test of 64 bit L1 + 32 bit PAE L2 on AMD.
> The later test currently fails on Intel (regardless of my patches).
> 
> Changes from V1:
>   - move only PDPTRS load to KVM_REQ_GET_NESTED_STATE_PAGES on VMX
>   - rebase on top of kvm/queue
>   - improve the KVM_GET_SREGS2 to have flag for PDPTRS
>     and remove padding
> 
> Patches to qemu will be send soon as well.

How did you want to handle integration with the removal of pdptrs_changed()?

https://lkml.kernel.org/r/68ff1249-2902-43d5-3dfd-35b1f14c4f90@redhat.com