openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

KVM: nVMX: Invalidate all EPTP contexts when emulating INVEPT for L1 

Free all L2 (guest_mmu) roots when emulating INVEPT for L1.  Outstanding
changes to the EPT tables managed by L1 need to be recognized, and
relying on KVM to always flush L2's EPTP context on nested VM-Enter is
dangerous.

Similar to handle_invpcid(), rely on kvm_mmu_free_roots() to do a remote
TLB flush if necessary, e.g. if L1 has never entered L2 then there is
nothing to be done.

Nuking all L2 roots is overkill for the single-context variant, but it's
the safe and easy bet.  A more precise zap mechanism will be added in
the future.  Add a TODO to call out that KVM only needs to invalidate
affected contexts.

Fixes: 14c07ad89f ("x86/kvm/mmu: introduce guest_mmu")
Reported-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200320212833.3507-4-sean.j.christopherson@intel.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2020-03-20 14:27:59 -07:00 committed by Paolo Bonzini
parent eed0030e4c
commit f8aa7e3958
1 changed files with 8 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
arch/x86/kvm/vmx/nested.c
View File

@ -5161,12 +5161,16 @@ static int handle_invept(struct kvm_vcpu *vcpu)
if (!nested_vmx_check_eptp(vcpu, operand.eptp))
return nested_vmx_failValid(vcpu,
VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);
/* TODO: sync only the target EPTP context. */
fallthrough;
case VMX_EPT_EXTENT_GLOBAL:
/*
* TODO: Sync the necessary shadow EPT roots here, rather than
* at the next emulated VM-entry.
*/
/*
* Nested EPT roots are always held through guest_mmu,
* not root_mmu.
*/
kvm_mmu_free_roots(vcpu, &vcpu->arch.guest_mmu,
KVM_MMU_ROOTS_ALL);
break;
default:
BUG_ON(1);