Switch DiskConfig over to using the newly extracted struct members as
used by all PCI based devices. The use of #[serde(flatten)] means that
this change has no impact on the JSON format that the data is stored as.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Introduce a common struct that can encompass all the config fields
used by devices that are PCI based. The use of `skip_serializing_if`
means that the iommu field will only be included if set (otherwise
falling back to default false). This neatly handles the devices that
don't support an iommu.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Add a `mergeable` field to `MemoryZoneConfig` so that KSM page merging
can be enabled selectively per memory zone rather than globally for all
guest RAM.
Previously, `MADV_MERGEABLE` was only controllable via the top-level
`--memory mergeable=on` flag, which applied uniformly to all regions.
With this change, users can leave boot memory unmerged while enabling
KSM only on hotplug zones:
--memory size=0,hotplug_method=virtio-mem
--memory-zone id=boot,size=512M,shared=on,mergeable=off
--memory-zone id=hotplug,size=256M,hotplug_size=1G,shared=off,mergeable=on
The `MemoryZone` runtime struct now carries the `mergeable` flag so
that both `allocate_address_space` and `add_ram_region` can apply
per-zone `MADV_MERGEABLE` instead of the global `self.mergeable`.
The top-level `--memory mergeable=on` path continues to work unchanged:
the default zone is synthesised from `MemoryConfig` and inherits its
`mergeable` value.
AI/LLM disclosure: this patch was co-authored with
GitHub Copilot and Claude Code (Opus 4.6).
Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Add a user-configurable option to control whether VFIO device MMIO BAR
regions are DMA-mapped into the host IOMMU address space.
This mapping is required for peer-to-peer DMA between devices (e.g.
NVLink, RDMA NIC accessing GPU VRAM). However, iommufd on upstream
kernels does not support mapping device MMIO pages (VM_PFNMAP), causing
IOMMU_IOAS_MAP to fail with -EFAULT. Kernels with the NVIDIA PFNMAP
workaround or future kernels with DMABUF-based mapping
(IOMMU_IOAS_MAP_FILE) handle this correctly.
The option defaults to `on` to preserve existing behavior. Users on
vanilla kernels using iommufd should set `vfio_p2p_dma=off` to skip
MMIO BAR DMA mapping.
A validation check ensures that `x_nv_gpudirect_clique` (which depends
on P2P DMA) cannot be used when `vfio_p2p_dma=off`.
Signed-off-by: Bo Chen <bchen@crusoe.ai>
This option allows user to configure VFIO device pass-through with
iommufd (e.g. vfio cdev mode) or not (e.g. vfio legacy mode).
Signed-off-by: Bo Chen <bchen@crusoe.ai>
When landlock support was added, creation of file descriptors was
moved out into a function called pre_create_console_devices, with the
idea being that this could be run before Landlock rules are applied
and access to all the necessary paths are dropped.
This idea didn't take reboots into account, though. When a VM is
rebooted, pre_create_console_devices is called again, but now the
Landlock rules have been applied, so they need to allow access to all
those paths anyway.
I imagine the way this was intended to work was that file descriptors
would be preserved across reboot, but that's not currently the case,
and it's not a trivial change to make because they get dropped when
the VM is destroyed. Longer term it would be ideal if Cloud
Hypervisor's implementation was more focused on file descriptors than
paths[1], and if created VMs only took references to file descriptors,
so they were easily preserved across reboots.
Fixes: b3e5738b4 ("vmm: Introduce ApplyLandlock trait")
Closes: https://github.com/cloud-hypervisor/cloud-hypervisor/issues/7547
Link: https://github.com/cloud-hypervisor/cloud-hypervisor/issues/7704 [1]
Signed-off-by: Alyssa Ross <hi@alyssa.is>
Add a per-disk lock_granularity parameter that lets users choose
between byte-range OFD locks and whole-file OFD locks:
--disk path=/foo.img,lock_granularity=byte-range
--disk path=/bar.img,lock_granularity=full
Byte-range is the default and matches QEMU behavior, working
best with storage backends where whole-file OFD locks are treated
as mandatory. The full option restores the original whole-file
locking for environments that depend on it.
The LockGranularityChoice enum and its FromStr impl live in the
block crate alongside the existing LockGranularity type. The
Block device converts the user-facing choice to the internal
LockGranularity at lock time, keeping device_manager.rs simple.
Closes: #7553
Signed-off-by: Victor Vieux <vieux@repl.it>
Add a core_scheduling option to --cpus with three modes of operation.
This feature takes advantage of a kernel feature that restricts
scheduling of processes on the SMT threads on the same core. This is
useful for mitigating certain classes of side-channel attacks and has
better performance that disabling SMT on the CPU.
- vm (default): All vCPU threads share one core scheduling cookie.
They may be co-scheduled on SMT siblings while host threads are
excluded - this has minimal performance impact and can even
potentially improve performance from co-location.
- vcpu: Each vCPU gets a unique cookie preventing any two vCPUs from
sharing SMT siblings. This has the strongest isolation but at some
compromise of performance.
- off: No core scheduling applied (old behaviour).
This isolation is done by the kernel maintaining a "cookie" - threads
with the same cookie can share the same core.
In vCPU mode each vCPU thread the cookie is created when the thread
starts and each gets a unique cookie. For VM mode the first vCPU thread
(the leader) will create the cookie. All other vCPU threads started (via
hotplug or during boot) will have that cookie shared to it.
EINVAL/ENODEV from prctl is silently ignored so this works transparently
on kernels older than 5.14 that lack PR_SCHED_CORE or when SMT disabled.
Full details of this kernel feature can be found at:
https://docs.kernel.org/admin-guide/hw-vuln/core-scheduling.html
This implementation was inspired by crosvm's implementation - in
particular the enable_core_scheduling() function.
This is challenging to test via integration testing but the logging of
the received cookie shows it working:
VM case:
cloud-hypervisor: 0.243102s: <vcpu1> INFO:vmm/src/cpu.rs:1247 -- vCPU 1: core scheduling cookie = 0x33e4c167
cloud-hypervisor: 0.243102s: <vcpu0> INFO:vmm/src/cpu.rs:1247 -- vCPU 0: core scheduling cookie = 0x33e4c167
vCPU case:
cloud-hypervisor: 0.089356s: <vcpu0> INFO:vmm/src/cpu.rs:1247 -- vCPU 0: core scheduling cookie = 0x13993ad6
cloud-hypervisor: 0.089380s: <vcpu1> INFO:vmm/src/cpu.rs:1247 -- vCPU 1: core scheduling cookie = 0xd48e86e
Signed-off-by: Rob Bradford <rbradford@meta.com>
Add an image_type to DiskConfig to specify the image type. If none is
specified autodetect the image type but disable potentially unsafe
behaviour in the QCOW2 backend by disabling the backing file support.
If the image type is autodetected then fix it in the config so that it
will be persistant across reboots and migrations/snapshot & restores.
This also handles the case where the image type was not specified as
part of the disk configuration.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Add sparse boolean configuration option to DiskConfig with a default
value of true to control disk space allocation behavior.
When sparse is true, the disk uses sparse allocation where deallocated
blocks are returned to the filesystem, and the DISCARD feature is
advertised to the guest.
When sparse is false, disk space is kept fully allocated and DISCARD
is not advertised.
WRITE_ZEROES is always advertised when the backend supports it,
regardless of the sparse setting.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Add an optional device_id string field to NumaConfig for identifying
PCI devices associated with a NUMA node. This is used by the Generic
Initiator support to map devices to their proximity domain.
Update OpenAPI spec (cloud-hypervisor.yaml) to include the
new device_id field in the NumaConfig schema.
The device_id is optional and parsed from the --numa parameter:
--numa "device_id=<device_id>,distances=[...],..."
The optional field is accepted but not used.
Signed-off-by: Saravanan D <saravanand@crusoe.ai>
The documentation says guest_numa_id is required to be unique and
therefore the parser() giving default value for non-existing
guest_numa_id with .unwrap_or(0) is dangerous.
Return a validation error if guest_numa_id is not provided instead
of silently defaulting to 0.
Signed-off-by: Saravanan D <saravanand@crusoe.ai>
Backing files (e.g. for QCOW2) interact badly with landlock since they
are not obvious from the initial VM configuration. Only enable their use
with an explicit option.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Add an option in the CLI to enable nested support.
Adding an option --cpu nested=on|off to the CPU
argument to enable nested support for Microsoft
Hypervisor. By default it is enabled for both KVM
and MSHV.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
While an IGVM is provided validation fails as there is
no kernel or firmware. This patch fixes the sev_snp boot
failure.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
For a graceful resource management of externally provided FDs in Cloud
Hypervisor, corresponding FDs need to be closed on a device removal.
This is the case for virtio-net devices using external FDs, for example.
With the fix introduced in this commit, we allow management software to
properly clean up resources, e.g., libvirt can clean up tap devices.
PS: CHV uses "added" and "removed", which has the same meaning as
hot device attach/hotplug and hot device detach/unplug.
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
Deserializing values as `-1` makes sense to prevent errors, so let's
keep it. However, serializing them differently adds confusion. For
example, a `ch-remote info` call should not report `-1` but the actual
FDs.
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
(1) The old messages are missing the "why" part. With this change, users
of Cloud Hypervisor have somehow more context and people looking at
the code perfectly know what's going on.
(2) Using warn! implies that the user should take action, but in this
case, there’s nothing the user can do. If the API is used correctly
and file descriptors are passed via an SCM_RIGHTS message over a
UNIX domain socket, everything works as intended. In that case,
there's no need to issue a warning — debug! is sufficient.
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
This change enables easier integration with third-party
tools by removing the requirement for a dummy IP address
when configuring tap devices. The modification applies to
both CLI and API interactions.
Previously, cloud-hypervisor would automatically set a
default static IP address (192.168.249.1) if none was provided.
This could lead to:
* multiple devices without explicit IP configurations
would end up with the same default IP
* unnecessary inclusion of this IP in firewall rules
* the IP address could clash with host networking and
routing
This introduces a new constraint:
When providing an IP, the mask must also be provided.
Removes warnings introduced in #7179.
Closes issue #7083.
Signed-off-by: Maximilian Güntner <code@mguentner.de>
arch::aarch64::fdt::create_cpu_nodes will always look at this if it
exists. (If it doesn't exist, this is a no-op —
add_rule_with_access() won't add rules for paths that don't exist.)
Fixes: b3e5738b4 ("vmm: Introduce ApplyLandlock trait")
Signed-off-by: Alyssa Ross <hi@alyssa.is>
Without write access to the directory the socket will go in, it's not
possible to create the socket.
I've tested outgoing connections from the VM, and they don't seem to
need read permissions on that directory to connect to a socket on the
host.
Fixes: b3e5738b4 ("vmm: Introduce ApplyLandlock trait")
Signed-off-by: Alyssa Ross <hi@alyssa.is>
path_beneath_rules() just needs the paths given to it to be
AsRef<Path>, so there's no need to create new PathBufs for it.
Signed-off-by: Alyssa Ross <hi@alyssa.is>
Raise the max number of supported (v)CPUs on kvm x86_64 hosts
to 8192 (the max allowed value of CONFIG_NR_CPUS in the Linux kernel).
Other platfroms keep their existing CPU limits pending further
development and testing.
The change has been tested on Intel and AMD hosts.
Signed-off-by: Barret Rhoden <brho@google.com>
Signed-off-by: Neel Natu <neelnatu@google.com>
Signed-off-by: Ofir Weisse <oweisse@google.com>
Signed-off-by: Peter Oskolkov <posk@google.com>
This commit removes the SGX support from cloud hypervisor. SGX support
was deprecated in May as part of #7090.
Signed-off-by: Shubham Chakrawar <schakrawar@crusoe.ai>
Currently, the following scenarios are supported by Cloud Hypervisor to
bootstrap a VM:
1. provide firmware
2. provide kernel
3. provide kernel + cmdline
4. provide kernel + initrd
5. provide kernel + cmdline + initrd
As the difference between `--firmware` and `--kernel` is not very clear
currently, especially as both use/support a Xen PVH entry, adding this
helps to identify the cause of misconfiguration.
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
This allows us to enable/disable the fw_cfg device via the cli
We can also now upload files into the guest vm using fw_cfg_items
via the cli
Signed-off-by: Alex Orozco <alexorozco@google.com>
Allow tap interfaces to be configured with an IPv6 address. The change
is fairly straightforward: we need to update the API types and CLI
parsing to accept either an IPv6 or IPv4 and then match on the IP
address type when the tap device is configured.
For IPv6 addresses, the netmask (prefix) must be provided at the same
time as the address itself (in the SIOCSIFADDR ioctl). They cannot be
configured separately. So we remove the separate "set_netmask" function
and convert "set_ip_addr" to also accept a netmask. For IPv4 addresses,
the IP address and netmask were already always set together, so this
should have no functional impact for users of IPv4 addresses.
Signed-off-by: Gregory Anders <ganders@cloudflare.com>
By introducing `imports_granularity="Module"` format strategy,
effectively groups imports from the same module into one line or block,
improving maintainability and readability.
Signed-off-by: Ruoqing He <heruoqing@iscas.ac.cn>
Historically the Cloud Hypervisor coding style has been to ensure that
all imports are ordered and placed in a single group. Unfortunately
cargo fmt has no support for ensuring that all imports are in a single
group so if whitespace lines were added as part of the import statements
then they would only be odered correctly in the group.
By adopting "group_imports="StdExternalCrate" we can enforce a style
where imports are placed in at most three groups for std, external
crates and the crate itself. Choosing a style enforceable by the tooling
reduces the reviewer burden.
Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
Pvmemcontrol provides a way for the guest to control its physical memory
properties, and enables optimizations and security features. For
example, the guest can provide information to the host where parts of a
hugepage may be unbacked, or sensitive data may not be swapped out, etc.
Pvmemcontrol allows guests to manipulate its gPTE entries in the SLAT,
and also some other properties of the memory map the back's host memory.
This is achieved by using the KVM_CAP_SYNC_MMU capability. When this
capability is available, the changes in the backing of the memory region
on the host are automatically reflected into the guest. For example, an
mmap() or madvise() that affects the region will be made visible
immediately.
There are two components of the implementation: the guest Linux driver
and Virtual Machine Monitor (VMM) device. A guest-allocated shared
buffer is negotiated per-cpu through a few PCI MMIO registers, the VMM
device assigns a unique command for each per-cpu buffer. The guest
writes its pvmemcontrol request in the per-cpu buffer, then writes the
corresponding command into the command register, calling into the VMM
device to perform the pvmemcontrol request.
The synchronous per-cpu shared buffer approach avoids the kick and busy
waiting that the guest would have to do with virtio virtqueue transport.
The Cloud Hypervisor component can be enabled with --pvmemcontrol.
Co-developed-by: Stanko Novakovic <stanko@google.com>
Co-developed-by: Pasha Tatashin <tatashin@google.com>
Signed-off-by: Yuanchu Xie <yuanchu@google.com>
This requires stashing the config values in `struct Vmm`. The configs
should be validated before before creating the VMM thread. Refactor the
code and update documentation where necessary.
The place where the rules are applied remain the same.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
Introduce ApplyLandlock trait and add implementations to VmConfig
elements with PathBufs. This trait adds config specific rules to
landlock ruleset.
Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Users can use this parameter to pass extra paths that 'vmm' and its
child threads can use at runtime. Hotplug is the primary usecase for
this parameter.
In order to hotplug devices that use local files: disks, memory zones,
pmem devices etc, users can use this option to pass the path/s that will
be used during hotplug while starting cloud-hypervisor. Doing this will
allow landlock to add required rules to grant access to these paths when
cloud-hypervisor process starts.
Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Signed-off-by: Wei Liu <liuwe@microsoft.com>
Users can use this cmdline option to enable/disable Landlock based
sandboxing while running cloud-hypervisor.
Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
When using multiple PCI segments, the 32-bit and 64-bit mmio
aperture is split equally between each segment. Add an option
to configure the 'weight'. For example, a PCI segment with a
`mmio32_aperture_weight` of 2 will be allocated twice as much
32-bit mmio space as a normal PCI segment.
Signed-off-by: Thomas Barrett <tbarrett@crusoeenergy.com>
The 'NetConfig' may contain FDs which can't be serialized correctly, as
FDs can only be donated from another process via a Unix domain socket
with `SCM_RIGHTS`. To avoid false use of the serialized FDs, this patch
explicitly set 'NetConfig' FDs as invalid for (de)serialization.
See: #6286
Signed-off-by: Bo Chen <chen.bo@intel.com>
On platforms where PCIe P2P is supported, inject a PCI capability into
NVIDIA GPU to indicate support.
Signed-off-by: Thomas Barrett <tbarrett@crusoeenergy.com>
The host data provided at launch. Data is passed
to the hypervisor during the completion of the
isolated import.
Host Data provided by the hypervisor during guest launch.
The firmware includes this value in all attestation
reports for the guest.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Currently the only way to set the affinity for virtio block threads is
to boot the VM, search for the tid of each of the virtio block threads,
then set the affinity manually. This commit adds an option to pin virtio
block queues to specific host cpus (similar to pinning vcpus to host
cpus). A queue_affinity option has been added to the disk flag in
the cli to specify a mapping of queue indices to host cpus.
Signed-off-by: acarp <acarp@crusoeenergy.com>
This commit adds the debug-console (or debugcon) device to CHV. It is a
very simple device on I/O port 0xe9 supported by QEMU and BOCHS. It is
meant for printing information as easy as possible, without any
necessary configuration from the guest at all.
It is primarily interesting to OS/kernel and firmware developers as they
can produce output as soon as the guest starts without any configuration
of a serial device or similar. Furthermore, a kernel hacker might use
this device for information of type B whereas information of type A are
printed to the serial device.
This device is not used by default by Linux, Windows, or any other
"real" OS, but only by toy kernels and during firmware development.
In the CLI, it can be configured similar to --console or --serial with
the --debug-console parameter.
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
