Summary of PR

This PR adds support for passing through /dev/kvm to sandbox containers, enabling KVM-accelerated virtual machines inside sandboxes instead of slower emulation.

Add SANDBOX_KVM_ENABLED environment variable to enable passing /dev/kvm to sandbox containers. When enabled, sandboxes can run KVM-accelerated virtual machines instead of using slower emulation.

This is useful for workloads that need to spin up VMs inside the sandbox, such as testing operating systems or running nested virtualization.

Further work

If there is interest from the community, I could polish the feature. One things that comes to mind is to only enable it for specific sandboxes, by having a checkbox somewhere when launching one.

Demo Screenshots/Videos

Not really a screenshot, but still prooves it works. This was executed inside a sandbox:

openhands@721d061d484b:/workspace/project$ ls -la /dev/kvm
crw-rw-rw- 1 nobody nogroup 10, 232 Mar 25 22:30 /dev/kvm
openhands@721d061d484b:/workspace/project$ qemu-system-x86_64 -accel kvm -m 512 -nographic -no-reboot &
[1] 2274
openhands@721d061d484b:/workspace/project$ sleep 2

[1]+ Stopped qemu-system-x86_64 -accel kvm -m 512 -nographic -no-reboot
openhands@721d061d484b:/workspace/project$ pkill qemu

Without this feature, /dev/kvm is not there. Also, the qemu command gives an error.

Change Type

• Bug fix
• New feature
• Breaking change
• Refactor
• Other (dependency update, docs, typo fixes, etc.)

Checklist

• I have read and reviewed the code and I understand what the code is doing.
• I have tested the code to the best of my ability and ensured it works as expected.

The changes are relatively straightforward and well written.

Release Notes

• Include this change in the Release Notes.

Add SANDBOX_KVM_ENABLED environment variable to enable passing /dev/kvm to sandbox containers. When enabled, sandboxes can run KVM-accelerated virtual machines instead of using slower emulation.