Commit Graph

7 Commits

Author SHA1 Message Date
Zide Chen
863e58e539 hv: nested: define software layout for VMCS12 and helper functions
Software layout of VMCS12 data is a contract between L1 guest and L0
hypervisor to run a L2 guest.

ACRN hypervisor caches the VMCS12 which is passed down from L1 hypervisor
by the VMPTRLD instructin. At the time of VMCLEAR, ACRN syncs the cached
VMCS12 back to L1 guest memory.

Tracked-On: #5923
Signed-off-by: Sainath Grandhi <sainath.grandhi@intel.com>
Signed-off-by: Zide Chen <zide.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@Intel.com>
2021-05-24 10:34:01 +08:00
Zide Chen
f5744174b5 hv: nested: support for VMPTRLD emulation
This patch emulates the VMPTRLD instruction. L0 hypervisor (ACRN) caches
the VMCS12 that is passed down from the VMPTRLD instruction, and merges it
with VMCS01 to create VMCS02 to run the nested VM.

- Currently ACRN can't cache multiple VMCS12 on one vCPU, so it needs to
  flushes active but not current VMCS12s to L1 guest.
- ACRN creates VMCS02 to run nested VM based on VMCS12:
  1) copy VMCS12 from guest memory to the per vCPU cache VMCS12
  2) initialize VMCS02 revision ID and host-state area
  3) load shadow fields from cache VMCS12 to VMCS02
  4) enable VMCS shadowing before L1 Vm entry

Tracked-On: #5923
Signed-off-by: Sainath Grandhi <sainath.grandhi@intel.com>
Signed-off-by: Zide Chen <zide.chen@intel.com>
2021-05-24 10:34:01 +08:00
Zide Chen
0a1ac2f4a0 hv: nested: support for VMXOFF emulation
This patch implements the VMXOFF instruction. By issuing VMXOFF,
L1 guest Leaves VMX Operation.

- cleanup VCPU nested virtualization context states in VMXOFF handler.
- implement check_vmx_permission() to check permission for VMX operation
  for VMXOFF and other VMX instructions.

Tracked-On: #5923
Signed-off-by: Sainath Grandhi <sainath.grandhi@intel.com>
Signed-off-by: Zide Chen <zide.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@Intel.com>
2021-05-24 10:34:01 +08:00
Zide Chen
3fdad3c6d1 hv: nested: check prerequisites to enter VMX operation
According to VMXON Instruction Reference, do the following checks in the
virtual hardware environment: vCPU CPL, guest CR0, CR4, revision ID
in VMXON region, etc.

Currently ACRN doesn't support 32-bit L1 hypervisor, and injects an #UD
exception if L1 hypervisor is not running in 64-bit mode.

Tracked-On: #5923
Signed-off-by: Zide Chen <zide.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@Intel.com>
2021-05-24 10:34:01 +08:00
Zide Chen
fc8f07e740 hv: nested: support for VMXON emulation
This patch emulates VMXON instruction. Basically checks some
prerequisites to enable VMX operation on L1 guest (next patch), and
prepares some virtual hardware environment in L0.

Tracked-On: #5923
Signed-off-by: Sainath Grandhi <sainath.grandhi@intel.com>
Signed-off-by: Zide Chen <zide.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@Intel.com>
2021-05-24 10:34:01 +08:00
Zide Chen
c9982e8c7e hv: nested: setup emulated VMX MSRs
We emulated these MSRs:

- MSR_IA32_VMX_PINBASED_CTLS
- MSR_IA32_VMX_PROCBASED_CTLS
- MSR_IA32_VMX_PROCBASED_CTLS2
- MSR_IA32_VMX_EXIT_CTLS
- MSR_IA32_VMX_ENTRY_CTLS
- MSR_IA32_VMX_BASIC: emulate VMCS revision ID, etc.
- MSR_IA32_VMX_MISC

For the following MSRs, we pass through the physical value to L1 guests:

- MSR_IA32_VMX_EPT_VPID_CAP
- MSR_IA32_VMX_VMCS_ENUM
- MSR_IA32_VMX_CR0_FIXED0
- MSR_IA32_VMX_CR0_FIXED1
- MSR_IA32_VMX_CR4_FIXED0
- MSR_IA32_VMX_CR4_FIXED1

Tracked-On: #5923
Signed-off-by: Zide Chen <zide.chen@intel.com>
Signed-off-by: Sainath Grandhi <sainath.grandhi@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
2021-05-16 19:05:21 +08:00
Zide Chen
4930992118 hv: nested: implement the framework for VMX MSR emulation
Define LIST_OF_VMX_MSRS which includes a list of MSRs that are visible to
L1 guests if nested virtualization is enabled.
- If CONFIG_NVMX_ENABLED is set, these MSRs are included in
  emulated_guest_msrs[].
- otherwise, they are included in unsupported_msrs[].

In this way we can take advantage of the existing infrastructure to
emulate these MSRs.

Tracked-On: #5923
Spick igned-off-by: Zide Chen <zide.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
2021-05-16 19:05:21 +08:00