[PATCH 0/2] KVM: VMX: Sanitize VM-Entry/VM-Exit pairs during setup

From: Sean Christopherson <seanjc@google.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Wanpeng Li <wanpengli@tencent.com>,
	Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
	kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	Chenyi Qiang <chenyi.qiang@intel.com>,
	Lei Wang <lei4.wang@intel.com>
Subject: [PATCH 0/2] KVM: VMX: Sanitize VM-Entry/VM-Exit pairs during setup
Date: Wed, 25 May 2022 21:04:45 +0000	[thread overview]
Message-ID: <20220525210447.2758436-1-seanjc@google.com> (raw)

Sanitize the VM-Entry/VM-Exit load+load and load+clear pairs when kvm_intel
is loaded instead of checking both controls at runtime.  Not sanitizing
means KVM ends up setting non-dynamic bits in the VMCS.

Add an opt-in knob to force kvm_intel to bail if an inconsistent pair is
detected instead of using a degraded and/or potentially broken setup.

Arguably patch 01 is stable material, but my mental coin flip came up
negative and I didn't Cc: stable.

And for patch 02, I'd definitely be favor of making it opt-out instead of
opt-in, but there's a non-zero chance that someone out there is running
KVM in a misconfigured VM...

Sean Christopherson (2):
  KVM: VMX: Sanitize VM-Entry/VM-Exit control pairs at kvm_intel load
    time
  KVM: VMX: Add knob to allow rejecting kvm_intel on inconsistent VMCS
    config

 arch/x86/kvm/vmx/capabilities.h | 13 +++-----
 arch/x86/kvm/vmx/vmx.c          | 55 +++++++++++++++++++++++++++++++--
 2 files changed, 56 insertions(+), 12 deletions(-)

base-commit: 90bde5bea810d766e7046bf5884f2ccf76dd78e9
-- 
2.36.1.124.g0e6072fb45-goog