[PATCH v3 0/8] This patch-set is to enable Guest CET support

From: Yang Weijiang
Date: Tue Feb 26 2019 - 01:32:48 EST


Control-flow Enforcement Technology (CET) provides protection against
return/jump-oriented programming (ROP) attacks. To make kvm Guest OS own
the capability, this patch-set is required. It enables CET related CPUID
report, xsaves/xrstors, vmx entry configuration etc. for Guest OS.

PATCH 1 : Define CET VMCS fields and bits.
PATCH 2/3 : Report CET feature support in CPUID.
PATCH 4 : Fix xsaves size calculation issue.
PATCH 5 : Pass through CET MSRs to Guest.
PATCH 6 : Set Guest CET state auto loading bit.
PATCH 7 : Enable CET xsaves bits support in XSS.
PATCH 8 : Add CET MSR user space access interface.

Changelog:
v3:
- Modified patches to make Guest CET independent to Host enabling.
- Added patch 8 to add user space access for Guest CET MSR access.
- Modified code comments and patch description to reflect changes.

v2:
- Re-ordered patch sequence, combined one patch.
- Added more description for CET related VMCS fields.
- Added Host CET capability check while enabling Guest CET loading bit.
- Added Host CET capability check while reporting Guest CPUID(EAX=7,
EXC=0).
- Modified code in reporting Guest CPUID(EAX=D,ECX>=1), make it clearer.
- Added Host and Guest XSS mask check while setting bits for Guest XSS.


Yang Weijiang (8):
KVM:VMX: Define CET VMCS fields and bits
KVM:CPUID: Define CET CPUID bits and CR4.CET master enable bit.
KVM:CPUID: Add CPUID support for Guest CET
KVM:CPUID: Fix xsaves area size calculation for CPUID.(EAX=0xD,ECX=1).
KVM:VMX: Pass through host CET related MSRs to Guest.
KVM:VMX: Load Guest CET via VMCS when CET is enabled in Guest
KVM:X86: Add XSS bit 11 and 12 support for CET xsaves/xrstors.
KVM:X86: Add user-space read/write interface for CET MSRs.

arch/x86/include/asm/kvm_host.h | 3 +-
arch/x86/include/asm/vmx.h | 8 ++++
arch/x86/kvm/cpuid.c | 67 ++++++++++++++++++++++++---------
arch/x86/kvm/vmx.c | 53 ++++++++++++++++++++++++--
arch/x86/kvm/x86.c | 46 ++++++++++++++++++++--
arch/x86/kvm/x86.h | 4 ++
6 files changed, 157 insertions(+), 24 deletions(-)

--
2.17.1