When NUMA placement is active and VFIO devices are cold-plugged,
create a pxb-pcie (PCIe Expander Bridge) per NUMA node that has
devices. Each pxb-pcie carries a numa_node property that gives the
guest kernel correct NUMA affinity for all PCI devices beneath it.
Root ports are created on each pxb-pcie bus instead of pcie.0, and
VFIODevice.Attach() assigns each device to the root port on its host
NUMA node's pxb bridge. Non-VFIO devices remain on pcie.0.
NUMA placement is "active" when there is more than one guest NUMA
node OR a single guest node mapped to a specific host node (the
latter happens when maybeRightSizeAutoNUMA() collapses a multi-node
sandbox to the GPU's host NUMA node). In both cases
buildNUMATopology() also emits the matching
memory-backend-ram,host-nodes=,policy=bind entries so guest memory
is sourced from the right host node.
So pxb-pcie can never capture a leaf virtio-pci device as the
default bus, every virtio-pci device emitter (NetDevice, VSOCK,
vhost-user-{net,scsi,blk,fs}) now appends bus=pcie.0 explicitly when
the machine actually exposes a pcie.0 root. Detection is done via a
new hasPCIeRoot() helper that returns true only for q35/virt machine
types — ppc64le's pseries (pci.0), s390x's s390-ccw-virtio (CCW
transport) and microvm (no PCI) intentionally skip the pin to avoid
"Bus 'pcie.0' not found" at startup.
This is the only QEMU mechanism that works for both regular and
confidential (TDX/SNP) guests, as it operates through the PCI bus
hierarchy rather than ACPI table injection.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
QEMU may not have spawned all vCPU threads when pinning starts, so
query_cpus_fast can return an incomplete list and leave some vCPUs
unpinned. To fix it, let's add exponential backoff retries before
pinning and fall back to available threads if retries are exhausted.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Make checkVCPUsPinning() NUMA-aware: when GuestNUMANodes are configured,
vCPU threads are pinned to host CPUs belonging to the same NUMA node as
the vCPU's guest NUMA node assignment via checkVCPUsPinningNUMA(),
preserving memory locality. vCPUs are distributed proportionally across
NUMA nodes, matching the distribution in buildNUMATopology().
Stop unconditionally stripping cpuset.mems in constrainGRPCSpec() and
container update(). When multi-NUMA is configured, translate host NUMA
node IDs to guest NUMA node IDs using translateHostMemsToGuest() before
forwarding to the agent. This allows the agent to enforce NUMA-aware
memory placement for containers.
Filter guest NUMA nodes at VM creation time: before calling CreateVM(),
prune GuestNUMANodes to only those whose HostCPUs intersect the sandbox
cpuset. This avoids exposing fake NUMA topology to the guest when
Kubernetes allocates CPUs from fewer nodes than the host has (e.g. all
CPUs from node 0 on a 2-node host), improving memory locality and
avoiding unnecessary cross-node memory traffic.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Signed-off-by: Zvonko Kaiser <zkaiser@nvidia.com>
Add sysfs-based host NUMA distance reading (GetHostNUMADistances) that
parses /sys/devices/system/node/nodeN/distance to mirror the host NUMA
distance matrix into the guest via -numa dist entries.
Implement buildNUMATopology() which translates the GuestNUMANodes
configuration into govmm NUMANode and NUMADist slices. Each guest NUMA
node gets a floor-divided share of vCPUs and memory, with the last node
absorbing any remainder. This handles the common Kata case of +1 VMM
overhead vCPU gracefully. Memory backends are selected based on
hugepages/virtio-fs/file-backed-mem configuration.
Guard multi-NUMA topology generation to amd64 and arm64 only, since
other architectures (s390x, riscv64) do not support QEMU NUMA/DIMM.
Wire buildNUMATopology() into CreateVM so the QEMU config includes NUMA
nodes and distances.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Signed-off-by: Zvonko Kaiser <zkaiser@nvidia.com>
Add PCISysFsDevicesNUMANode property and GetPCIDeviceNUMANode() helper
to read /sys/bus/pci/devices/<BDF>/numa_node when discovering VFIO
devices. Store the result in the new NUMANode field on VFIODev (-1 for
unknown/no affinity).
Wire NUMA node detection into both GetAllVFIODevicesFromIOMMUGroup()
(legacy VFIO path) and GetDeviceFromVFIODev() (IOMMUFD path) so every
discovered VFIO device carries its host NUMA node.
Add validateVFIODeviceNUMAPlacement() which runs at the end of
buildNUMATopology(). It checks every cold-plugged VFIO device's host
NUMA node against the guest NUMA topology and logs a warning if a device
is on a host NUMA node not covered by any guest NUMA node (indicating
potential cross-NUMA memory access overhead), or an info message
confirming correct placement.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Signed-off-by: Zvonko Kaiser <zkaiser@nvidia.com>
Make cpuTopology() NUMA-aware by accepting a numNUMANodes parameter.
When multiple NUMA nodes are configured, restructure the SMP topology so
that Sockets=numNUMA and Cores=ceil(maxvcpus/numNUMA), grouping vCPUs by
socket per NUMA node. Use ceiling division so that uneven vCPU counts
(e.g. the +1 VMM overhead vCPU that Kata adds) produce a QEMU-valid SMP
topology where MaxCPUs == Sockets * Cores * Threads.
When numNUMANodes <= 1, the existing flat topology (Sockets=maxvcpus,
Cores=1) is preserved.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Signed-off-by: Zvonko Kaiser <zkaiser@nvidia.com>
Docker 29.5+ adds a private time namespace to container bundles by
default, but kata agent only supports the classic namespace set and
then fails with "invalid namespace type".
Let's strip time namespaces in both the Go and rust runtimes before the
spec reaches the agent, matching how network and cgroup namespaces are
handled.
Fixes: #13080
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
When the jailer is in use (the default for kata-fc), cmd.Process.Pid in
fcInit() is the jailer's PID, not firecracker's. The jailer forks +
execs firecracker as a separate child and exits. fc.info.PID was
therefore stored as the (soon-to-be-dead) jailer PID.
At sandbox shutdown, fcEnd() calls WaitLocalProcess(fc.info.PID, SIGTERM, ...).
syscall.Kill on the dead jailer PID returns ESRCH, WaitLocalProcess
returns nil immediately, and the real firecracker microVM never
receives a signal. It gets reparented to init and stays alive
indefinitely, holding open resources from the host. Over many
container lifecycles this becomes a serious resource leak.
Read the real PID from <jailerRoot>/firecracker.pid, which firecracker
itself writes after the exec. Update fc.info.PID with that value so all
downstream code (fcEnd, Save/Load, kill-0 alive checks, NewProc) operates
on the actual firecracker process.
Also fix a small adjacent bug in Sandbox.Stop where the per-container
teardown loop ignored the force flag, causing any container.stop error
to short-circuit Stop before stopVM ran.
Signed-off-by: Sebastian Wolf <swolf@nvidia.com>
We sometimes get this error when creating the pod sandbox:
failed to create shim task: Failed to add qdisc for network index 2 : device or resource busy.
Adding a linear backoff retry when adding the qdisc to help mitigate the issue at the source and avoid the cascading error.
Signed-off-by: Mayeul Blanzat <mayeul.blanzat@datadoghq.com>
Because intptr() returns a fresh pointer on every call, those comparisons compared addresses,
never values, so every check evaluated to false.
As a result /dev/null, /dev/urandom, /dev/ptmx, /dev/loop-control and /dev/loop*
were appended to devices allowlist for sandbox_cgroup
even when the runtime spec already listed them, producing duplicate entries.
Switch to nil-safe value comparisons via a type switch on the cgroup device type
and dereferenced *d.Major / *d.Minor,
keeping the same detection semantics but actually matching existing entries.
Assisted-By: Claude 4.7
Signed-off-by: PiotrProkop <pprokop@nvidia.com>
When sandbox_cgroup_only is enabled, the kata shim threads inherit
the sandbox device cgroup. For container rootfs whose mount source
is a regular file backed by a loop device (notably the blockfile
snapshotter), containerd's mount package opens /dev/loop-control to
allocate a free /dev/loopN and then opens that block node to attach
the backing file. Neither device is on the sandbox cgroup allowlist,
so both opens fail with EPERM.
This change adds /dev/loop-control (char 10:237) and the /dev/loopN
block nodes (block major 7, any minor) to the sandbox device cgroup
allowlist when sandbox_cgroup_only is true, mirroring the existing
treatment of /dev/null, /dev/urandom and /dev/ptmx. The additions
are gated on SandboxCgroupOnly because that is the only mode in
which the shim itself is constrained by this cgroup.
Assisted-By: Claude 4.7
Signed-off-by: PiotrProkop <pprokop@nvidia.com>
Now shipped in the vendored code tarball.
Drop the git tree status check since it isn't needed anymore.
Also stop building with `-mod=vendor`. This requires to
expose GOMODCACHE as suggested by Fabiano Fidêncio.
Signed-off-by: Greg Kurz <groug@kaod.org>
Interfaces whose drivers do not register a specific netlink kind
(e.g. mlx5 Scalable Functions) are reported with the generic type
"device". The endpoint creation code did not handle this type,
causing sandbox creation to fail with:
"Unsupported network interface: device"
This is particularly visible on arm64 with Mellanox ConnectX NICs
using Scalable Functions, where the ethtool BusInfo returns a
non-PCI identifier (e.g. "mlx5_core.sf.4") so isPhysicalIface()
cannot classify the interface as physical either.
Handle "device" type interfaces the same way as veth endpoints,
connecting them through a TAP + TC-filter bridge.
Additionally, relax getLinkForEndpoint() for VethEndpoint so it
accepts the concrete link type returned by the kernel instead of
asserting *netlink.Veth. A "device" type interface wrapped in a
VethEndpoint returns *netlink.Device from LinkByName(), which
would fail the strict type assertion. All callers only need
link.Attrs(), so accepting any link type is safe.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.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>
Add a new extensible GetDiagnosticData RPC that retrieves diagnostic
information from the guest VM. The request carries a log_type string
field to specify what kind of data is requested, and a container_id
field to identify the target container.
The first supported log_type is "termination_log", which reads the
Kubernetes termination message file from inside the guest. This is
needed for shared_fs=none configurations where the host cannot
directly access the guest filesystem.
On the Go runtime side, the container stop() path now calls
GetDiagnosticData to copy the termination message to the host
when running with NoSharedFS and the terminationMessagePolicy
annotation is set to "File". The call is best-effort: failures
are logged as warnings rather than blocking container teardown.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Signed-off-by: Silenio Quarti <silenio_quarti@ca.ibm.com>
This is not related to this PR, but rather to #12734, which ended up not
running the `make src/agent generate-protocols`.
While here, let's also fix it.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
The hardcoded DEFAULT_LAUNCH_PROCESS_TIMEOUT of 6 seconds in the kata
agent is insufficient for environments with NVIDIA GPUs and NVSwitches,
where the attestation-agent needs significantly more time to collect
evidence during initialization (e.g. ~2 seconds per NVSwitch).
When the timeout expires, the agent (PID 1) exits with an error, causing
the guest kernel to perform an orderly shutdown before the
attestation-agent has finished starting.
Make this timeout configurable via the kernel parameter
agent.launch_process_timeout (in seconds), preserving the 6-second
default for backward compatibility. The Go runtime is wired up to pass
this value from the TOML config's [agent.kata] section through to the
kernel command line.
The NVIDIA GPU configs set the new default to 15 seconds.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
Made-with: Cursor
Docker 26+ configures container networking (veth pair, IP addresses,
routes) after task creation rather than before. Kata's endpoint scan
runs during CreateSandbox, before the interfaces exist, resulting in
VMs starting without network connectivity (no -netdev passed to QEMU).
Add RescanNetwork() which runs asynchronously after the Start RPC.
It polls the network namespace until Docker's interfaces appear, then
hotplugs them to QEMU and informs the guest agent to configure them
inside the VM.
Additional fixes:
- mountinfo parser: find fs type dynamically instead of hardcoded
field index, fixing parsing with optional mount tags (shared:,
master:)
- IsDockerContainer: check CreateRuntime hooks for Docker 26+
- DockerNetnsPath: extract netns path from libnetwork-setkey hook
args with path traversal protection
- detectHypervisorNetns: verify PID ownership via /proc/pid/cmdline
to guard against PID recycling
- startVM guard: rescan when len(endpoints)==0 after VM start
Fixes: #9340
Signed-off-by: llink5 <llink5@users.noreply.github.com>
Add two new configuration knobs that control the logical and physical
sector sizes advertised by virtio-blk devices to the guest:
block_device_logical_sector_size (config file)
block_device_physical_sector_size (config file)
io.katacontainers.config.hypervisor.blk_logical_sector_size (annotation)
io.katacontainers.config.hypervisor.blk_physical_sector_size (annotation)
The annotation names are abbreviated relative to the config file keys
because Kubernetes enforces a 63-character limit on annotation name
segments, and the full names would exceed it.
Both settings default to 0 (let QEMU decide). When set, they are passed
as logical_block_size and physical_block_size in the QMP device_add
command during block device hotplug.
Setting logical_sector_size smaller then container filesystem
block size will cause EINVAL on mount. The physical_sector_size can
always be set independently.
Values must be 0 or a power of 2 in the range [512, 65536]; other
values are rejected with an error at sandbox creation time.
Signed-off-by: PiotrProkop <pprokop@nvidia.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>
Replace hardcoded NVIDIA vendor ID (0x10de) and class (0x030) checks
with a vendor-agnostic lookup table (cdiDeviceKind) that maps PCI
vendor/class pairs to CDI device kinds. This makes it straightforward
to add support for new device types by adding entries to the table.
Refactor siblingAnnotation to resolve device BDFs once upfront and
reuse them for both CDI type detection and sibling matching, eliminating
redundant sysfs reads. Devices not in the lookup table (e.g. NVSwitches)
are skipped with errNoSiblingFound, while known device types that fail
to match a sibling produce a hard error.
Consolidate the hot-plug and cold-plug device loops into a single loop
over extracted container paths, removing duplicated filtering logic.
Export GetPCIDeviceProperty from the device drivers package to allow
vendor/class lookup from sysfs in the container annotation path.
Signed-off-by: Zvonko Kaiser <zkaiser@nvidia.com>
* Introduces the `emptydir_mode` config flag to allow instructing the runtime
to create a block device for emptyDir volumes.
* The block device is created in the original emptyDir folder on the host
so that Kubelet can monitors its disk usage and evict the pod if it exceeds
its sizeLimit. This matches runc and virtio-fs.
* The block device's disk image file is sparse to minimize host disk
footprint.
Fixes: #10560
Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
Some VMMs support plugging a disk as an image file instead of a block device,
so we adapt the runtime to support that.
Signed-off-by: Alex Lyn <alex.lyn@antgroup.com>
Signed-off-by: Aurélien Bombo <abombo@microsoft.com>
Co-authored-by: Aurélien Bombo <abombo@microsoft.com>
Virtio-mmio transport is not hardened for confidential computing (unlike
virtio-pci). Reject config that would use virtio-blk-mmio for rootfs/block
when confidential_guest is set, so CoCo guests only use virtio-blk-pci.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
The remote hypervisor delegates VM creation to a remote service.
The VM runs on cloud infrastructure, not the local host kernel.
So requiring a KVM/MSHV device is semantically wrong and would
cause a hard failure on any host where these devices are absent
(e.g., a VM that doesn't expose nested virtualization).
Skip sandboxDevices() entirely when the configured hypervisor type
is remoteHypervisor{}.
Signed-off-by: Hyounggyu Choi <Hyounggyu.Choi@ibm.com>
Stop computing and setting mem-reserve and pref64-reserve on PCIe root
ports and switch ports. Remove getBARsMaxAddressableMemory() which
scanned host GPU BARs to pre-calculate these values.
The previous approach only considered GPU devices (IsGPU(), class
0x0302) when scanning for BAR sizes, so devices like NVSwitches (class
0x0680) with their 32MB non-prefetchable BAR0 were not accounted for
and received the 4MB default. Additionally, GetTotalAddressableMemory()
classifies BARs by 32/64-bit address width rather than by the
prefetchable flag that QEMU's mem-reserve vs pref64-reserve maps to.
Modern QEMU introspects VFIO device BARs when they are attached to
root ports and sizes the MMIO windows accordingly. Modern OVMF
(edk2-stable202502+) automatically calculates the 64-bit PCI MMIO
aperture based on the BARs of actually present devices during PCI
enumeration. Omitting the reserve parameters lets QEMU and OVMF
handle MMIO window sizing correctly for all device types including
GPUs, NVSwitches, and NICs without requiring host-side BAR scanning.
This also removes the nvpci dependency from qemu_arch_base.go.
Signed-off-by: Zvonko Kaiser <zkaiser@nvidia.com>
Modern OVMF (edk2-stable202502 and later) automatically sizes the
64-bit PCI MMIO aperture based on the BARs of actually attached
devices during PCI enumeration. The opt/ovmf/X-PciMmio64Mb fw_cfg
hint is no longer needed to ensure large-BAR devices like NVIDIA
GPUs receive adequate MMIO space.
The previous approach was fragile: the runtime scanned host PCI
devices to estimate the required aperture size, but only considered
GPU devices (class 0x0302), missing NVSwitches and other devices
with large BARs. Removing this code avoids confusion about MMIO
sizing responsibility.
Signed-off-by: Zvonko Kaiser <zkaiser@nvidia.com>
Different kubernetes distributions, such as k0s, use a different kubelet
root dir location instead of the default /var/lib/kubelet, so ConfigMap
and Secret volume propagation were failing.
This adds a kubelet_root_dir config option that the go runtime uses when
matching volume paths and kata-deploy now sets it automatically for k0s
via a drop-in file.
runtime-rs does not need this option: it identifies ConfigMap/Secret,
projected, and downward-api volumes by volume-type path segment
(kubernetes.io~configmap, etc.), not by kubelet root prefix.
Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com>
This commit adds logic to properly handle memory hotplug
for QemuCCWVirtio in the ExecMemdevAdd() path.
The new logic is triggered only when virtio-mem is enabled.
Signed-off-by: Hyounggyu Choi <Hyounggyu.Choi@ibm.com>
ResizeMemory() already contains the virtio-mem resize logic.
However, hotplugAddMemory(), which is invoked via a different
path, lacked this handling and always fell back to the pc-dimm
path, even when virtio-mem was configured.
This commit adds virtio-mem resize handling to hotplugAddMemory().
It also adds corresponding unit tests.
Signed-off-by: Hyounggyu Choi <Hyounggyu.Choi@ibm.com>
Specify raw image format for all guest block devices.
- Attempting to auto-detect the image format from CLH would be riskier
for the Host.
- Creating a new raw image file, auto-detecting its format, and then
creating a filesystem from the Guest onto the block device is no
longer supported by CLH v51. Therefore, Kata CI's k8s-block-volume.bats
would fail without specifying the raw format when hot plugging its block
device.
- See cloud-hypervisor/cloud-hypervisor@b3e8e2a for additional information.
Signed-off-by: Dan Mihai <dmihai@microsoft.com>
```
v51.1
=====
This is a bug fix release. The following issues have been addressed:
* Fix image_type in OpenAPI definition (#7734)
v51.0
=====
This release has been tracked in v51.0 group of our roadmap project.
Security Fixes
This release fixes a security vulnerability in disk image handling.
Details can be found in GHSA-jmr4-g2hv-mjj6.
* A new `backing_files=on|off` option has been added to `--disk` to
explicitly control whether QCOW2 backing files are permitted. This
defaults to `off` to prevent the loading of backing files entirely.
(#7685)
* Explicit image type specification via the user interface, removing
reliance on format autodetection (#7728).
* Prevent sector-zero writes for autodetected raw images (#7728).
Significant QCOW2 v3 Improvements
A large number of QCOW2 v3 specification features have been implemented:
* RAW backing file support for QCOW2 overlays (#7570)
* Zero bit in L2 entries (#7627)
* Incompatible feature bit validation (#7612)
* Dirty bit support (#7636)
* Variable refcount widths (1 to 64-bit) (#7633)
* Corrupt bit detection and marking (#7639)
* Autoclear feature bits handling (#7648)
* Thread safety fix for multiple virtio queues (`num_queues > 1`)
(#7661)
* Correct zero-fill for reads beyond backing file size (#7678)
* Live disk resize support (#7687)
ACPI Generic Initiator Support
ACPI Generic Initiator Affinity (SRAT Type 5) support has been added
to associate VFIO-PCI devices with dedicated memory/CPU-less NUMA
nodes. This enables the guest OS to make NUMA-aware memory allocation
decisions for device workloads. A new `device_id` parameter has been
added to `--numa` for specifying VFIO devices. (#7626)
Block Device DISCARD and WRITE_ZEROES Support
The `virtio-blk` device now supports `DISCARD` and `WRITE_ZEROES`
operations for QCOW2 and RAW image formats. This enables thin
provisioning and efficient space reclamation when guests trim
filesystems. A new `sparse=on|off` option has been added to `--disk` to
control disk space management: `sparse=on` (default) enables thin
provisioning with space reclamation, while `sparse=off` provides thick
provisioning with consistent I/O latency. (#7666)
Notable Performance Improvements
* Transparent Huge Pages (THP) support has been extended to cover
anonymous shared memory (`shared=on`) via `madvise`. Previously, THP
was only used for non-shared memory. (#7646)
* The `vhost-user-net` device now uses the default set of vhost-user
virtio features, including `VIRTIO_F_RING_INDIRECT_DESC`, which
provides a performance improvement. (#7653)
MSHV Support Improvements
* Optimize CPU state update after emulation by only updating special
registers when changed (#7603)
* Enable SMT for guests with `threads_per_core > 1` (#7668)
* Stub `save_data_tables()` to unblock VM pause/resume (#7692)
* Handle `GHCB_INFO_SPECIAL_DBGPRINT` VMG exit in SEV-SNP guest exit
handler (#7703)
* Fix CVM boot failure on MSHV (#7548)
* Fix CPU topology detection for multithreaded configurations (#7576)
Notable Bug Fixes
* Fix VFIO device hot-remove leaving group and container file
descriptors open, preventing re-add (#7676)
* Fix snapshot restore when backing file is on read-only storage with
`shared=false` (#7674)
* Enforce `VIRTIO_BLK_F_RO` even if guest does not negotiate it
(#7705)
* Fix read-only block device FLUSH requests from OVMF preventing VMs
from booting (#7706)
* Fix vhost-user device not properly dropping unowned file descriptors
(#7679)
* Fix `vhost-user-block` `get_config` interoperability (#7617)
* Fix vsock TOCTOU race condition by copying packet header from guest
memory before processing (#7530)
* Fix vsock handling of large TX packets spanning multiple data
descriptors (#7680)
* Add `gettid()` to all seccomp filters (#7596)
* Fix MAC address parsing that wrongly allowed `+` instead of hex
characters (#7579)
* Improve UUID parse error message and `--net` fd help text (#7702)
* Fix various inconsistencies in our OpenAPI specification file
(#7716, #7726)
* Various documentation fixes (#7602, #7606)
```
Signed-off-by: Dan Mihai <dmihai@microsoft.com>
I think that c727332b0e
broke the arm unit test by removing the arm specific overrides,
so update the expected output
Signed-off-by: stevenhorsman <steven@uk.ibm.com>
QF1001: Distributing negation across terms and flipping operators, makes it
easy for humans to process expressions at a time, vs evaluating a whole block
and then flipping it and can allow for earlier exit
Signed-off-by: stevenhorsman <steven@uk.ibm.com>
fixup: demorgans
GenericDevice is an embedded (anonymous) field in the device struct, so its fields
and methods are "promoted" to the outer struct, so we go straight to it.
Signed-off-by: stevenhorsman <steven@uk.ibm.com>