runtime-rs: Set disable_guest_empty_dir = true by default#452
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Bug: https://microsoft.visualstudio.com/OS/_workitems/edit/43668151 Rationale: This is a temporary solution for optimizing memory usage for the current mechanism of requesting resources through pod Limit annotations: - if no Limits are specified and hence WorkloadMemMB is 0, set a default value 'StaticWorkloadDefaultMem' to allocate a default amount of memory for use for containers in the sandbox in addition to the base memory - if Limits are specified, the base memory and the sum of Limits are allocated. The end user needs to be aware of the minimum memory requirements for their pods, otherwise the pod will be stuck in the ContainerCreating state Testing: Manual testing, creating pods with Limits and without limits, and with two containers where each container has a limit, tested with integration in a SPEC file where the config variables were set via environment variables via the make command Adapted by @mfrw from 3.1.0 to apply to 3.2.0 Signed-off-by: Muhammad Falak R Wani <mwani@microsoft.com> Signed-off-by: Manuel Huber <mahuber@microsoft.com> runtime: Remove unused VMM options for mem alloc - We only ever tested these fork changes with CLH+MSHV - Remove these options as we don't use QEMU/FC Signed-off-by: Manuel Huber <mahuber@microsoft.com>
This branch starts introducing additional scripting to build, deploy
and evaluate the components used in AKS' Pod Sandboxing and
Confidential Containers preview features. This includes the capability
to build the IGVM file and its reference measurement file for remote
attestation.
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
tools: Improve igvm-builder and node-builder/azure-linux scripting
- Support for Mariner 3 builds using OS_VERSION variable
- Improvements to IGVM build process and flow as described in README
- Adoption of using only cloud-hypervisor-cvm on CBL-Mariner
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
tools: Add package-tools-install functionality
- Add script to install kata-containers(-cc)-tools bits
- Minor improvements in README.md
- Minor fix in package_install
- Remove echo outputs in package_build
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
tools: Enable setting IGVM SVN
- Allow setting SVN parameter for IGVM build scripting
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
node-builder: introduce BUILD_TYPE variable
This lets developers build and deploy Kata in debug mode without having to make
manual edits to the build scripts.
With BUILD_TYPE=debug (default is release):
* The agent is built in debug mode.
* The agent is built with a permissive policy (using allow-all.rego).
* The shim debug config file is used, ie. we create the symlink
configuration-clh-snp-debug.toml <- configuration-clh-snp.toml.
For example, building and deploying Kata-CC in debug mode is now as simple as:
make BUILD_TYPE=debug all-confpods deploy-confpods
Also do note that make still lets you override the other variables even after
setting BUILD_TYPE. For example, you can use the production shim config with
BUILD_TYPE=debug:
make BUILD_TYPE=debug SHIM_USE_DEBUG_CONFIG=no all-confpods deploy-confpods
Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
node-builder: introduce SHIM_REDEPLOY_CONFIG
See README: when SHIM_REDEPLOY_CONFIG=no, the shim configuration is NOT
redeployed, so that potential config changes made directly on the host
during development aren't lost.
Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
node-builder: Use img for Pod Sandboxing
Switch from UVM initrd to image format
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
node-builder: Adapt README instructions
- Sanitize containerd config snippet
- Set podOverhead for Kata runtime class
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
tools: Adapt AGENT_POLICY_FILE path
- Adapt path in uvm_build.sh script to comply
with the usptream changes we pulled in
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
node-builder: Use Azure Linux 3 as default path
- update recipe and node-builder scripting
- change default value on rootfs-builder
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
node-builder: Deploy-only for AzL3 VMs
- split deployment sections in node-builder README.md
- install jq, curl dependencies within IGVM script
- add path parameter to UVM install script
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
node-builder: Minor updates to README.md
- no longer install make package, is part of meta package
- remove superfluous popd
- add note on permissive policy for ConfPods UVM builds
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
node-builder: Updates to README.md
- with the latest 3.2.0.azl4 package on PMC, can remove OS_VERSION parameter
and use the make deploy calls instead of copying files by hand for variant
I (now aligned with Variant II)
- with the latest changes on msft-main, set the podOverhead to 600Mi
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
node-builder: Fix SHIM_USE_DEBUG_CONFIG behavior
Using a symlink would create a cycle after calling this script again when
copying the final configuration at line 74 so we just use cp instead.
Also, I moved this block to the end of the file to properly override the final
config file.
Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
node-builder: Build and install debug configuration for pod sandboxing
For ease of debugging, install a configuration-clh-debug.toml for pod
sandboxing as we do in Conf pods.
Signed-off-by: Cameron Baird <cameronbaird@microsoft.com>
runtime: remove clh-snp config file usage in makefile
Not needed to build vanilla kata
Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
package_tools_install.sh: include nsdax.gpl.c
Include nsdax.gpl.c
Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
node-builder: fix typo in string comparison
This also fixes a shellcheck error and lets us require the
shellcheck-required job:
In ./tools/osbuilder/node-builder/azure-linux/uvm_build.sh line 34:
if [ -z "${UVM_KERNEL_HEADER_DIR}}" ]; then
^-- SC2157 (error): Argument to -z is always false due to literal strings.
Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
docs: node-builder: fix static check error
This fixes the below static check error to follow up on the infra fix from
kata-containers#11646:
2025-07-31T19:32:45.0031829Z time="2025-07-31T19:32:44.990004665Z" level=fatal msg="found 2 parse errors:\nfile=\"tools/osbuilder/node-builder/azure-linux/README.md\": duplicate heading: \"Set up environment\" (heading: {Name:Set up environment MDName:Set up environment LinkName:set-up-environment Level:2})\nfile=\"tools/osbuilder/node-builder/azure-linux/README.md\": duplicate heading: \"Install build dependencies\" (heading: {Name:Install build dependencies MDName:Install build dependencies LinkName:install-build-dependencies Level:2})" commit=1d17f56b1aa7a880468b8e25d14467c92dca8eeb name=kata-check-markdown pid=9075 source=check-markdown version=0.0.1
Note: that is likely flagged because having two headings with the same
name, even under different sections, makes it impossible to create a
canonical heading link in Markdown.
This should eventually be squashed into the node-builder commit.
Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
docs: node-builder: Remove references to moby-containerd-cc
As we adopted containerd2, we remove references to our prior
forked containerd version.
Signed-off-by: Manuel Huber <mahuber@microsoft.com>
node-builder: 2Mb aligned guest image size
Build the mariner guest image using IMAGE_SIZE_ALIGNMENT_MB=2.
Signed-off-by: Dan Mihai <dmihai@microsoft.com>
to-squash: node-builder: add reference to README.md
This is needed to avoid the following static-checks error:
2025-08-05T21:27:20.0028337Z [static-checks.sh:808] ERROR: Document tools/osbuilder/node-builder/azure-linux/README.md is not referenced
This commit is to be squashed into the node-builder commit.
Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
After these changes:
1. The value of the K8s runtime class memory overhead:
- Covers the memory usage from all the Host-side components (mainly
the Kata Shim and the VMM).
- Doesn't include the memory usage from any Guest-side components.
2. The value of a pod memory limit specified by the user:
- Is equal to the memory size of the Pod VM.
- Includes the memory usage from all the Guest-side components
(mainly user's workload, the Guest kernel, and the Kata Agent)
- Doesn't include the memory usage from any Host-side components.
Signed-off-by: Dan Mihai <dmihai@microsoft.com>
runtime: fix `make test`
This addresses the following errors from `make test` to allow us to require
that upstream CI:
https://github.com/microsoft/kata-containers/actions/runs/16656407213/job/47142422035?pr=392#step:13:53
Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
- similar to the static_sandbox_default_workload_mem option, assign a default number of vcpus to the VM when no limits are given, 1 vcpu in this case - similar to commit c7b8ee9, do not allocate additional vcpus when limits are provided Signed-off-by: Manuel Huber <mahuber@microsoft.com>
Point to msft-preview Signed-off-by: Manuel Huber <mahuber@microsoft.com> Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
For our Kata UVM, we know we need at least 128MB of memory to prevent instability in the guest. Enforce this constraint with a descriptive error to prevent users from destabilizing the UVM with faulty k8s configurations. Signed-off-by: Cameron Baird <cameronbaird@microsoft.com>
If memory limit is set and less than minimum, set it to minimum. This is to to account for kata-containers@0ec3403 Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
Add Microsoft mandatory file SECURITY.md Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
- Change Makefile to point to fork - Change versions.yaml to point to proper version on fork Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
This change mirrors host networking into the guest as before, but now also includes the default gateway neighbor entry for each interface. Pods using overlay/synthetic gateways (e.g., 169.254.1.1) can hit a first-connect race while the guest performs the initial ARP. Preseeding the gateway neighbor removes that latency and makes early connections (e.g., to the API Service) deterministic. Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
This is a fork temporary measure to unblock CI required tests in our fork, while we find a way to remove the 'main' hard codes from upstream. Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
Background: * `pull_request` runs on the PR branch code and has access to secrets ONLY if the PR is from microsoft/kata-containers (i.e. NOT from an external contributor who forked the repo). * `pull_request_target` runs on the trusted main branch code by default and has access to secrets for any PR. Reference: https://docs.github.com/en/actions/reference/workflows-and-actions/events-that-trigger-workflows#pull_request Upstream uses `pull_request_target` (and manually checks out the PR code) to have access to secrets for PRs from external contributors, however we don't expect external PRs, hence we can use `pull_request`. Furthermore, since `pull_request_target` only runs from the default branch, we need to use `pull_request` anyway as we have multiple leading branches (i.e., msft-main, msft-preview, and release branches). https://github.blog/changelog/2025-11-07-actions-pull_request_target-and-environment-branch-protections-changes/ Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
set default to msft-preview Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
use upstream cloud-hypervisor. This is to unblock the CI and let CLH build Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
update target branch to msft-preview Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
This fixes a CI static check failure Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
- tests that deploy pods with too small of a memory limit - try to set a minimum memory limit for some containerd tests - tests that use runners we don't have - tests that depend on pushing to GHCR Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
Enable VFIO device pass-through at VM creation time on Cloud Hypervisor, in addition to the existing hot-plug path. Signed-off-by: Roaa Sakr <romoh@microsoft.com>
Regenerate CH client against v51.1 Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
The recently-added nested property is true by default, but is not supported yet on MSHV. See cloud-hypervisor/cloud-hypervisor#7408 for additional information. Signed-off-by: Dan Mihai <dmihai@microsoft.com>
This cloud-hypervisor is a directory, so it needs "rm -rf" instead of "rm -f". Signed-off-by: Dan Mihai <dmihai@microsoft.com>
disable Kata Containers CI / kata-containers-ci-on-push / run-kata-deploy-tests / run-kata-deploy-tests (qemu, k3s) Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
`cargo check` was introduced in 3f1533a to check that Cargo.lock is in sync with Cargo.toml. However, if there are uncommitted changes in the working tree, the current invocation will immediately fail because of the `git diff` call, which is frustrating for local development. As it turns out, `cargo clippy` is a superset of `cargo check`, so we can simply pass `--locked` to `cargo clippy` to detect Cargo.lock issues. This is tested with the following change: diff --git a/src/agent/Cargo.lock b/src/agent/Cargo.lock index 96b6c67..e1963af 100644 --- a/src/agent/Cargo.lock +++ b/src/agent/Cargo.lock @@ -4305,6 +4305,7 @@ checksum = "8f50febec83f5ee1df3015341d8bd429f2d1cc62bcba7ea2076759d315084683" name = "test-utils" version = "0.1.0" dependencies = [ - "libc", "nix 0.26.4", ] which results in the following output: $ make -C src/agent check make: Entering directory '/kata-containers/src/agent' standard rust check... cargo fmt -- --check cargo clippy --all-targets --all-features --release --locked \ -- \ -D warnings error: the lock file /kata-containers/src/agent/Cargo.lock needs to be updated but --locked was passed to prevent this If you want to try to generate the lock file without accessing the network, remove the --locked flag and use --offline instead. make: *** [../../utils.mk:184: standard_rust_check] Error 101 make: Leaving directory '/kata-containers/src/agent' Signed-off-by: Aurélien Bombo <abombo@microsoft.com> Signed-off-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
This reverts commit c06b470.
Build and install both runtime-rs and runtime-go configs and binaries side by side:
- runtime-go:
/usr/local/bin/containerd-shim-kata-v2-go
/usr/local/share/defaults/kata-containers/configuration-clh.toml
/usr/local/share/defaults/kata-containers/configuration-clh-debug.toml
- runtime-rs:
/usr/local/bin/containerd-shim-kata-v2-rs
/usr/local/share/defaults/kata-containers/configuration-cloud-hypervisor.toml
/usr/local/share/defaults/kata-containers/configuration-cloud-hypervisor-debug.toml
Also add USE_RUNTIME_RS variable and default to "yes". This controls which runtime binary and configuration will be installed
to /usr/local/bin/containerd-shim-kata-v2 and /usr/local/share/defaults/kata-containers/configuration.toml respectively.
Also install kata-ctl (runtime-rs equivalent of kata-runtime) so we can exec into the UVM when using runtime-rs
Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
This is a port from b03db3e into runtime-rs Rationale: This is a temporary solution for optimizing memory usage for the current mechanism of requesting resources through pod Limit annotations: - if no Limits are specified and hence WorkloadMemMB is 0, set a default value 'StaticWorkloadDefaultMem' to allocate a default amount of memory for use for containers in the sandbox in addition to the base memory - if Limits are specified, the base memory and the sum of Limits are allocated. The end user needs to be aware of the minimum memory requirements for their pods, otherwise the pod will be stuck in the ContainerCreating state Testing: Manual testing, creating pods with Limits and without limits, and with two containers where each container has a limit, tested with integration in a SPEC file where the config variables were set via environment variables via the make command Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
This is a port from 7ddec33 into runtime-rs After these changes: 1. The value of the K8s runtime class memory overhead: - Covers the memory usage from all the Host-side components (mainly the Kata Shim and the VMM). - Doesn't include the memory usage from any Guest-side components. 2. The value of a pod memory limit specified by the user: - Is equal to the memory size of the Pod VM. - Includes the memory usage from all the Guest-side components (mainly user's workload, the Guest kernel, and the Kata Agent) - Doesn't include the memory usage from any Host-side components. Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
This is a port from 9af9844 Plus ports an existing behaviour from runtime-go to also add the vcpus. See https://github.com/fidencio/kata-containers/blob/e2476f587c472d5d217df9c75cdb80193dd85994/src/runtime/pkg/oci/utils.go#L1232 - similar to the static_sandbox_default_workload_mem option, assign a default number of vcpus to the VM when no limits are given, 1 vcpu in this case - similar to commit c7b8ee9, do not allocate additional vcpus when limits are provided Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
This is a runtime-rs port for kata-containers@7973e4e The recently-added nested property is true by default, but is not supported yet on MSHV. See cloud-hypervisor/cloud-hypervisor#7408 for additional information. Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
upstream cherry-pick of 9404104 Enable the following optimizations when building runtime-rs in release mode: - lto: true - codegen-units=1: Setting these reduce the binary size and improve performance at the cost of longer build times. Without these flags: - build time: 4m 55s - binary size: 51 MB With these flags: - build time: 7m 21s - binary size: 38MB Per kata-containers#1125 and local experiments, a smaller binary size leads to a smaller shim memory footprint. - https://nnethercote.github.io/perf-book/build-configuration.html#codegen-units - https://nnethercote.github.io/perf-book/build-configuration.html#link-time-optimization Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
InitialSizeManager::setup_config() is responsible for applying the
sandbox workload sizing (computed from containerd/CRI-O sandbox
annotations) to the hypervisor configuration before VM creation.
Previously, the workload vCPU count was only logged but never actually
added to default_vcpus, so the VM was always created with only the base
vCPUs from the configuration/annotations. This caused the
k8s-sandbox-vcpus-allocation test to fail with qemu-snp-runtime-rs:
a pod with default_vcpus=0.75 and a container CPU limit of 1.2 should
see ceil(0.75 + 1.2) = 2 vCPUs, but only got 1.
Additionally, the workload memory was being added to default_memory
unconditionally, diverging from the Go runtime which only applies both
CPU and memory additions when static_sandbox_resource_mgmt is enabled.
In the non-static path, adding workload resources here would cause
double-counting: once from setup_config() at sandbox creation, and
again from update_cpu_resources()/update_mem_resources() when
individual containers are added.
Guard both additions behind static_sandbox_resource_mgmt, matching the
Go runtime's behavior in src/runtime/pkg/oci/utils.go:
if sandboxConfig.StaticResourceMgmt {
sandboxConfig.HypervisorConfig.NumVCPUsF += sandboxConfig.SandboxResources.WorkloadCPUs
sandboxConfig.HypervisorConfig.MemorySize += sandboxConfig.SandboxResources.WorkloadMemMB
}
Fixes: k8s-sandbox-vcpus-allocation test failure on qemu-snp-runtime-rs
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Made-with: Cursor
If using static management and initial size manager uses 0 for CPU or memory, we add default static values to the hv config Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
based on current runtime-go behaviour introduced in kata-containers#9195 When using static resources, always set maxvcpus value equal to the vcpus value. This is because the static resources case does not support dynamic CPU hotplugging, and therefore the maximum number of vCPUs should be limited to the number of vCPUs. Booting with a high number of max vCPUs is a bit slower compared to a lower number. Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
Due to importing resource management patches to runtime-rs, these tests: - run-nerdctl-tests (dragonball) - run-nydus (active, dragonball) - run-nydus (lts, dragonball) Are failing with: vmm action error: MachineConfig(InvalidVcpuCount(0)) Signed-off-by: Saul Paredes <saulparedes@microsoft.com>
This makes the runtime share the host Kubelet emptyDir folder with the guest instead of the agent creating an empty folder in the container rootfs. Doing so enables the Kubelet to track emptyDir usage and evict greedy pods. In other words, with virtio-fs the container rootfs uses host storage whether this is true or false, however with true, Kata uses the k8s emptyDir folder so the sizeLimit is properly enforced by k8s. Addresses the emptyDir part of kata-containers#12203. Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
Porting the runtime-go change. Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
sprt
changed the title
disable_guest_empty_dir = true by default
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Pull request overview
This PR changes the default behavior for Kubernetes emptyDir handling by setting disable_guest_empty_dir = true in the generated default configuration, and adds a Linux runtime optimization to reuse an already-shared guest path for repeated mounts of the same host source within a sandbox.
Changes:
- Set
DEFDISABLEGUESTEMPTYDIR := truein both the Go runtime and Rust runtime Makefiles so generated configs defaultdisable_guest_empty_dirto true. - Add
srcGuestMapcaching inFilesystemShare.ShareFile()(Linux) to reuse a previously created guest path for the same mount source when FS sharing is not supported.
Reviewed changes
Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
src/runtime/virtcontainers/fs_share_linux.go |
Adds a per-sandbox cache from mount source to guest path to allow reuse across containers. |
src/runtime/Makefile |
Flips the default disable_guest_empty_dir value used in generated Go runtime configs. |
src/runtime-rs/Makefile |
Flips the default disable_guest_empty_dir value used in generated Rust runtime configs. |
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danmihai1
approved these changes
May 26, 2026
Comment on lines
+434
to
+435
| f.srcGuestMapLock.Lock() | ||
| defer f.srcGuestMapLock.Unlock() |
Member
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As per the other code review, a defer is not really needed here, and can be unnecessarily delaying the release of the map (especially if someone in the future adds code somewhere after line 436).
romoh
approved these changes
May 26, 2026
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Port of #449 to msft-preview.
Will merge after the ongoing msft-preview rebase.