dsg/crosvm
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
crosvm/hypervisor
History
Kaiyi Li 909a54913e hypervisor: test interuptibility on special interrupt window 
The interrupt window includes:
* sti
* mov ss

On real x86 processors, after certain instructions(mov ss/pop ss/sti), an interrupt is guaranteed not to be delivered for exactly one instruction, not just an indefinite amount of time.

For mov ss/pop ss, this is architecturally defined so that loading a new stack segment plus stack pointer together can be done atomically (without an interrupt handler running in the middle and using a half-initialized stack address).

For sti, this delay allows the kernel to do sti ret, without an interrupt handler running before we return from the current routine.

However, the virtualization instructions allow the hypervisor to inject interrupts. Therefore, it's the hypervisor/VMM's responsbility to not to deliver an interrupt on an unexpected places on the guest.

This test uses port IO to trigger VMEXIT before and after mov ss or sti, and tests the interruptibility under different occasions. It also tests when the interrupt will be delivered.

TEST=./tools/dev_container cargo nextest run --workspace --profile=default -E 'package(hypervisor) & binary(hypervisor_virtualization) & test(interruptible)'  --retries 0 --no-capture
BUG=b:334055761

Change-Id: Ib800c5e8054b4bcc4b20899d2cea1b113081c0e7
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/5568137
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Commit-Queue: Kaiyi Li <kaiyili@google.com>
Reviewed-by: Judson Powers <judsonp@google.com>
2024-05-28 16:46:05 +00:00
..
hypervisor_test_macro hypervisor: convenient macro to generate an array from inline assemblies 2024-05-21 19:31:17 +00:00
src hypervisor: fill in Vcpu panic reason for haxm. 2024-05-22 18:15:47 +00:00
tests hypervisor: test interuptibility on special interrupt window 2024-05-28 16:46:05 +00:00
Cargo.toml Cargo.toml: avoid "*" versions for external crates 2024-05-22 01:01:42 +00:00
README.md hypervisor/README.md: add qualcomm contacts for gunyah 2023-11-29 19:20:17 +00:00

README.md

Hypervisor Support

Multiple hypervisor backends are supported. See Advanced Usage for overriding the default backend.

Hypervisors added to crosvm must meet the following requirements:

  • Hypervisor code must be buildable in crosvm upstream.
    • Within reason, crosvm maintainers will ensure the hypervisor's code continues to build.
  • Hypervisors are not required to be tested upstream.
    • We can't require testing upstream because some hypervisors require specialized hardware.
    • When not tested upstream, the hypervisor's maintainers are expected to test it downstream. If a change to crosvm breaks something downstream, then the hypervisor's maintainers are expected to supply the fix and can't expect a revert of the culprit change to be accepted upstream.

KVM

  • Platforms: Linux
  • Tested upstream: yes

KVM is crosvm's preferred hypervisor for Linux.

WHPX

HAXM

Android Specific

The hypervisors in this section are used as backends of the Android Virtualization Framework.

Geniezone

Gunyah