On Thu, Aug 6, 2020 at 10:14 AM Oliver Upton <oupton@xxxxxxxxxx> wrote:
>
> To date, KVM has allowed guests to use paravirtual interfaces regardless
> of the configured CPUID. While almost any guest will consult the
> KVM_CPUID_FEATURES leaf _before_ using PV features, it is still
> undesirable to have such interfaces silently present.
>
> This series aims to address the issue by adding explicit checks against
> the guest's CPUID when servicing any paravirtual feature. Since this
> effectively changes the guest/hypervisor ABI, a KVM_CAP is warranted to
> guard the new behavior.
>
> Patches 1-2 refactor some of the PV code in anticipation of the change.
> Patch 3 introduces the checks + KVM_CAP. Finally, patch 4 fixes some doc
> typos that were noticed when working on this series.
>
> v1 => v2:
> - Strip Change-Id footers (checkpatch is your friend!)
>
> v2 => v3:
> - Mark kvm_write_system_time() as static
>
> Parent commit: f3633c268354 ("Merge tag 'kvm-s390-next-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-next-5.6")
>
> Oliver Upton (4):
> kvm: x86: encapsulate wrmsr(MSR_KVM_SYSTEM_TIME) emulation in helper
> fn
> kvm: x86: set wall_clock in kvm_write_wall_clock()
> kvm: x86: only provide PV features if enabled in guest's CPUID
> Documentation: kvm: fix some typos in cpuid.rst
>
> Documentation/virt/kvm/api.rst | 11 +++
> Documentation/virt/kvm/cpuid.rst | 88 +++++++++++-----------
> arch/x86/include/asm/kvm_host.h | 6 ++
> arch/x86/kvm/cpuid.h | 16 ++++
> arch/x86/kvm/x86.c | 122 +++++++++++++++++++++++--------
> include/uapi/linux/kvm.h | 1 +
> 6 files changed, 171 insertions(+), 73 deletions(-)
>
> --
> 2.28.0.236.gb10cc79966-goog
>
Ping :)
