diff options
| author | Peter Feiner <pfeiner@google.com> | 2017-06-30 17:26:31 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2017-07-03 11:19:54 +0200 |
| commit | ac8d57e5734389da18633d4e8cc030fe10843da7 (patch) | |
| tree | cc5aec1dd7bd4f36366aa6a064f9970c1e77c20d /arch/x86/include/asm/kvm_host.h | |
| parent | dcdca5fed5f6ef2521f927ba3b5cd6b328054be1 (diff) | |
kvm: x86: mmu: allow A/D bits to be disabled in an mmu
Adds the plumbing to disable A/D bits in the MMU based on a new role
bit, ad_disabled. When A/D is disabled, the MMU operates as though A/D
aren't available (i.e., using access tracking faults instead).
To avoid SP -> kvm_mmu_page.role.ad_disabled lookups all over the
place, A/D disablement is now stored in the SPTE. This state is stored
in the SPTE by tweaking the use of SPTE_SPECIAL_MASK for access
tracking. Rather than just setting SPTE_SPECIAL_MASK when an
access-tracking SPTE is non-present, we now always set
SPTE_SPECIAL_MASK for access-tracking SPTEs.
Signed-off-by: Peter Feiner <pfeiner@google.com>
[Use role.ad_disabled even for direct (non-shadow) EPT page tables. Add
documentation and a few MMU_WARN_ONs. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/include/asm/kvm_host.h')
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 9be890893885..1588e9e3dc01 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -257,7 +257,8 @@ union kvm_mmu_page_role { unsigned cr0_wp:1; unsigned smep_andnot_wp:1; unsigned smap_andnot_wp:1; - unsigned :8; + unsigned ad_disabled:1; + unsigned :7; /* * This is left at the top of the word so that |