5ef384a60f
Updated Hyper-V Enlightened VMCS specification lists several new fields for the following features: - PerfGlobalCtrl - EnclsExitingBitmap - Tsc Scaling - GuestLbrCtl - CET - SSP Update the definition. Note, the updated spec also provides an additional CPUID feature flag, CPUIDD.0x4000000A.EBX BIT(0), for PerfGlobalCtrl to workaround a Windows 11 quirk. Despite what the TLFS says: Indicates support for the GuestPerfGlobalCtrl and HostPerfGlobalCtrl fields in the enlightened VMCS. guests can safely use the fields if they are enumerated in the architectural VMX MSRs. I.e. KVM-on-HyperV doesn't need to check the CPUID bit, but KVM-as-HyperV must ensure the bit is set if PerfGlobalCtrl fields are exposed to L1. https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/tlfs Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> [sean: tweak CPUID name to make it PerfGlobalCtrl only] Signed-off-by: Sean Christopherson <seanjc@google.com> Acked-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20220830133737.1539624-3-vkuznets@redhat.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.