Commit Graph

156 Commits

Author SHA1 Message Date
Rob Bradford
83066cf58e vmm: Set a default maximum physical address size
When using PVH for booting (which we use for all firmwares and direct
kernel boot) the Linux kernel does not configure LA57 correctly. As such
we need to limit the address space to the maximum 4-level paging address
space.

If the user knows that their guest image can take advantage of the
5-level addressing and they need it for their workload then they can
increase the physical address space appropriately.

This PR removes the TDX specific handling as the new address space limit
is below the one that that code specified.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-10-01 08:59:15 -07:00
William Douglas
46f6d9597d vmm: Switch to using the serial_manager for serial input
This change switches from handling serial input in the VMM thread to
its own thread controlled by the SerialManager.

The motivation for this change is to avoid the VMM thread being unable
to process events while serial input is happening and vice versa.

The change also makes future work flushing the serial buffer on PTY
connections easier.

Signed-off-by: William Douglas <william.douglas@intel.com>
2021-09-17 11:15:35 +01:00
Alyssa Ross
330b5ea3be vmm: notify virtio-console of pty resizes
When a pty is resized (using the TIOCSWINSZ ioctl -- see ioctl_tty(2)),
the kernel will send a SIGWINCH signal to the pty's foreground process
group to notify it of the resize.  This is the only way to be notified
by the kernel of a pty resize.

We can't just make the cloud-hypervisor process's process group the
foreground process group though, because a process can only set the
foreground process group of its controlling terminal, and
cloud-hypervisor's controlling terminal will often be the terminal the
user is running it in.  To work around this, we fork a subprocess in a
new process group, and set its process group to be the foreground
process group of the pty.  The subprocess additionally must be running
in a new session so that it can have a different controlling
terminal.  This subprocess writes a byte to a pipe every time the pty
is resized, and the virtio-console device can listen for this in its
epoll loop.

Alternatives I considered were to have the subprocess just send
SIGWINCH to its parent, and to use an eventfd instead of a pipe.
I decided against the signal approach because re-purposing a signal
that has a very specific meaning (even if this use was only slightly
different to its normal meaning) felt unclean, and because it would
have required using pidfds to avoid race conditions if
cloud-hypervisor had terminated, which added complexity.  I decided
against using an eventfd because using a pipe instead allows the child
to be notified (via poll(2)) when nothing is reading from the pipe any
more, meaning it can be reliably notified of parent death and
terminate itself immediately.

I used clone3(2) instead of fork(2) because without
CLONE_CLEAR_SIGHAND the subprocess would inherit signal-hook's signal
handlers, and there's no other straightforward way to restore all signal
handlers to their defaults in the child process.  The only way to do
it would be to iterate through all possible signals, or maintain a
global list of monitored signals ourselves (vmm:vm::HANDLED_SIGNALS is
insufficient because it doesn't take into account e.g. the SIGSYS
signal handler that catches seccomp violations).

Signed-off-by: Alyssa Ross <hi@alyssa.is>
2021-09-14 15:43:25 +01:00
Rob Bradford
b6b686c71c vmm: Shutdown VMM if API thread panics
See: #3031

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-09-10 10:52:08 -07:00
Rob Bradford
c2144b5690 vmm, virtio-console: Move input reading into virtio-console thread
Move the processing of the input from stdin, PTY or file from the VMM
thread to the existing virtio-console thread. The handling of the resize
of a virtio-console has not changed but the name of the struct used to
support that has been renamed to reflect its usage.

Fixes: #3060

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-09-02 21:17:33 +01:00
Rob Bradford
d92707afc5 vmm: Introduce a SerialBuffer for buffering serial output
Introduce a dynamic buffer for storing output from the serial port. The
SerialBuffer implements std::io::Write and can be used in place of the
direct output for the serial device.

The internals of the buffer is a vector that grows dynamically based on
demand up to a fixed size at which point old data will be overwritten.
Currently the buffer is only flushed upon writes.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-09-02 13:52:18 +01:00
Rob Bradford
63637eba31 vmm: Simplify epoll handling for VMM main loop
Remove the indirection of a dispatch table and simply use the enum as
the event data for the events.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-08-31 21:30:11 +01:00
Rob Bradford
4d2a4e2805 vmm: Handle epoll events for PTYs separately
Use two separate events for the console and serial PTY and then drive
the handling of the inputs on the PTY separately. This results in the
correct behaviour when both console and serial are attached to the PTY
as they are triggered separately on the epoll so events are not lost.

Fixes: #3012

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-08-25 13:33:32 +01:00
Bo Chen
7d38a1848b virtio-devices, vmm: Fix the '--seccomp false' option
We are relying on applying empty 'seccomp' filters to support the
'--seccomp false' option, which will be treated as an error with the
updated 'seccompiler' crate. This patch fixes this issue by explicitly
checking whether the 'seccomp' filter is empty before applying the
filter.

Signed-off-by: Bo Chen <chen.bo@intel.com>
2021-08-18 10:42:19 +02:00
Bo Chen
08ac3405f5 virtio-devices, vmm: Move to the seccompiler crate
Fixes: #2929

Signed-off-by: Bo Chen <chen.bo@intel.com>
2021-08-18 10:42:19 +02:00
Rob Bradford
53b2e19934 vmm: Add support for hotplugging user devices
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-08-12 13:19:04 +01:00
Sebastien Boeuf
71c7dff32b vmm: Fix the error handling logic when migration fails
The code wasn't doing what it was expected to. The '?' was simply
returning the error to the top level function, meaning the Err() case in
the match was never hit. Moving the whole logic to a dedicated function
allows to identify when something got wrong without propagating to the
calling function, so that we can still stop the dirty logging and
unpause the VM.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2021-08-10 12:36:58 -07:00
Sebastien Boeuf
db444715fd vmm: Shutdown VM after migration succeeded
In case the migration succeeds, the destination VM will be correctly
running, with potential vhost-user backends attached to it. We can't let
the source VM trying to reconnect to the same backends, which is why
it's safer to shutdown the source VM.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2021-08-10 12:36:58 -07:00
Sebastien Boeuf
5a83ebce64 vmm: Notify Migratable objects about migration being complete
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2021-08-10 12:36:58 -07:00
Sebastien Boeuf
0411064271 vmm: Refactor migration through Migratable trait
Now that Migratable provides the methods for starting, stopping and
retrieving the dirty pages, we move the existing code to these new
functions.

No functional change intended.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
2021-08-05 06:07:00 -07:00
Bo Chen
902fe20d41 vmm: Add fallback handling for sending live migration
This patch adds a fallback path for sending live migration, where it
ensures the following behavior of source VM post live-migration:

1. The source VM will be paused only when the migration is completed
successfully, or otherwise it will keep running;

2. The source VM will always stop dirty pages logging.

Fixes: #2895

Signed-off-by: Bo Chen <chen.bo@intel.com>
2021-08-03 09:26:12 +01:00
Bo Chen
ca09638491 vmm: Add CPUID compatibility check for snapshot/restore
Signed-off-by: Bo Chen <chen.bo@intel.com>
2021-07-28 09:26:02 +02:00
Bo Chen
0835198ddd vmm: Factorize CPUID check for live-migration and snapshot/restore
This patch adds a common function "Vmm::vm_check_cpuid_compatibility()"
to be shared by both live-migration and snapshot/restore.

Signed-off-by: Bo Chen <chen.bo@intel.com>
2021-07-28 09:26:02 +02:00
Bo Chen
6d9c1eb638 arch, vmm: Add CPUID check to the 'Config' step of live migration
We now send not only the 'VmConfig' at the 'Command::Config' step of
live migration, but also send the 'common CPUID'. In this way, we can
check the compatibility of CPUID features between the source and
destination VMs, and abort live migration early if needed.

Signed-off-by: Bo Chen <chen.bo@intel.com>
2021-07-28 09:26:02 +02:00
Bo Chen
5e0d498582 hypervisor, vmm: Add dynamic control of logging dirty pages
This patch extends slightly the current live-migration code path with
the ability to dynamically start and stop logging dirty-pages, which
relies on two new methods added to the `hypervisor::vm::Vm` Trait. This
patch also contains a complete implementation of the two new methods
based on `kvm` and placeholders for `mshv` in the `hypervisor` crate.

Fixes: #2858

Signed-off-by: Bo Chen <chen.bo@intel.com>
2021-07-26 09:19:35 -07:00
Bo Chen
5768dcc320 vmm: Refactor slightly vm_boot and 'control_loop'
It ensures all handlers for `ApiRequest` in `control_loop` are
consistent and minimum and should read better.

No functional changes.

Signed-off-by: Bo Chen <chen.bo@intel.com>
2021-06-24 16:01:39 +02:00
Bo Chen
1075209e2a vmm: Handle ApiRequest::VmCreate in a separate function
It simplifies a bit the `Vmm::control_loop` and reads better to be
consistent with other `ApiRequest` handlers. Also, it removes the
repetitive `ApiError::VmAlreadyCreated` and makes `ApiError::VmCreate`
useful.

No functional changes.

Signed-off-by: Bo Chen <chen.bo@intel.com>
2021-06-24 16:01:39 +02:00
Bo Chen
b5bcdbaf48 misc: Upgrade to use the vm-memory crate w/ dirty-page-tracking
As the first step to complete live-migration with tracking dirty-pages
written by the VMM, this commit patches the dependent vm-memory crate to
the upstream version with the dirty-page-tracking capability. Most
changes are due to the updated `GuestMemoryMmap`, `GuestRegionMmap`, and
`MmapRegion` structs which are taking an additional generic type
parameter to specify what 'bitmap backend' is used.

The above changes should be transparent to the rest of the code base,
e.g. all unit/integration tests should pass without additional changes.

Signed-off-by: Bo Chen <chen.bo@intel.com>
2021-06-03 08:34:45 +01:00
renlei4
65a39f43cb vmm: support restore KVM clock in migration
In migration, vm object is created by new_from_migration with
NULL kvm clock. so vm.set_clock will not be called during vm resume.
If the guest using kvm-clock, the ticks will be stopped after migration.

As clock was already saved to snapshot, add a method to restore it before
vm resume in migration. after that, guest's kvm-clock works well.

Signed-off-by: Ren Lei <ren.lei4@zte.com.cn>
2021-05-20 14:32:49 +01:00
Rob Bradford
b282ff44d4 vmm: Enhance boot with info!() level messages
These messages are predominantly during the boot process but will also
occur during events such as hotplug.

These cover all the significant steps of the boot and can be helpful for
diagnosing performance and functionality issues during the boot.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-05-18 20:45:38 +02:00
Dayu Liu
8160c2884b docs: Fix some typos in docs and comments
Fix some typos or misspellings without functional change.

Signed-off-by: Dayu Liu <liu.dayu@zte.com.cn>
2021-05-18 17:19:12 +01:00
Rob Bradford
496ceed1d0 misc: Remove unnecessary "extern crate"
Now all crates use edition = "2018" then the majority of the "extern
crate" statements can be removed. Only those for importing macros need
to remain.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-05-12 17:26:11 +02:00
Rob Bradford
b8f5911c4e misc: Remove unused errors from public interface
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-05-11 13:37:19 +02:00
William Douglas
b8779ddc9e vmm: Create the api socket fd to pass to the http server
Instead of using the http server's method to have it create the
fd (causing the http thread to need to support the socket, bind and
listen syscalls). Create the socket fd in the vmm thread and use the
http server's new method supporting passing in this fd for the api
socket.

Signed-off-by: William Douglas <william.douglas@intel.com>
2021-04-29 09:44:40 +01:00
William Douglas
767b4f0e59 main: Enable the api-socket to be passed as an fd
To avoid race issues where the api-socket may not be created by the
time a cloud-hypervisor caller is ready to look for it, enable the
caller to pass the api-socket fd directly.

Avoid breaking current callers by allowing the --api-socket path to be
passed as it is now in addition to through the path argument.

Signed-off-by: William Douglas <william.r.douglas@gmail.com>
2021-04-26 14:40:49 -07:00
Rob Bradford
9762c8bc28 vmm: Address Rust 1.51.0 clippy issue (upper_case_acroynms)
warning: name `LocalAPIC` contains a capitalized acronym
   --> vmm/src/cpu.rs:197:8
    |
197 | struct LocalAPIC {
    |        ^^^^^^^^^ help: consider making the acronym lowercase, except the initial letter: `LocalApic`
    |
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#upper_case_acronyms

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-03-26 11:32:09 +00:00
Rob Bradford
9440304183 vmm: http: Error out earlier if we can't create API server
This removes a panic inside the API thread.

Fixes: #2395

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-03-17 11:30:26 +00:00
Rob Bradford
9b0996a71f vmm, main: Optionalise creation of API server
Only if we have a valid API server path then create the API server. For
now this has no functional change there is a default API server path in
the clap handling but rather prepares to do so optionally.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-03-17 11:30:26 +00:00
Rob Bradford
5bc311184e build: Remove url crate dependency
This removes multiple transitive dependencies and speeds up our build.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-03-12 16:52:55 +01:00
Rob Bradford
7f96eb2b67 vmm: migration: Simplify url socket handling in migration code
Extract URL handling to a common function and simplify to remove url
crate dependency.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-03-12 16:52:55 +01:00
William Douglas
56028fb214 Try to restore pty configuration on reboot
When a vm is created with a pty device, on reboot the pty fd (sub
only) will only be associated with the vmm through the epoll event
loop. The fd being polled will have been closed due to the vm itself
dropping the pty files (and potentially reopening the fd index to a
different item making things quite confusing) and new pty fds will be
opened but not polled on for input.

This change creates a structure to encapsulate the information about
the pty fd (main File, sub File and the path to the sub File). On
reboot, a copy of the console and serial pty structs is then passed
down to the new Vm  instance which will be used instead of creating a
new pty device.

This resolves the underlying issue from #2316.

Signed-off-by: William Douglas <william.r.douglas@gmail.com>
2021-03-05 18:34:52 +01:00
Rob Bradford
05a2b3fac2 vmm: Remove "tempfile" dependency from vmm
This was completely unused.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-02-22 14:29:53 +01:00
Rob Bradford
9260c4c10e vmm: Use event!() for some key VM actions
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-02-18 16:15:13 +00:00
Rob Bradford
707bb0ba72 vmm: Simplify return path of vm_boot
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-02-16 18:38:57 +01:00
Rob Bradford
9c5be6f660 build: Remove unnecessary Result<> returns
If the function can never return an error this is now a clippy failure:

error: this function's return value is unnecessarily wrapped by `Result`
   --> virtio-devices/src/watchdog.rs:215:5
    |
215 | /     fn set_state(&mut self, state: &WatchdogState) -> io::Result<()> {
216 | |         self.common.avail_features = state.avail_features;
217 | |         self.common.acked_features = state.acked_features;
218 | |         // When restoring enable the watchdog if it was previously enabled. We reset the timer
...   |
223 | |         Ok(())
224 | |     }
    | |_____^
    |
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_wraps

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-02-11 18:18:44 +00:00
William Douglas
48963e322a Enable pty console
Add the ability for cloud-hypervisor to create, manage and monitor a
pty for serial and/or console I/O from a user. The reasoning for
having cloud-hypervisor create the ptys is so that clients, libvirt
for example, could exit and later re-open the pty without causing I/O
issues. If the clients were responsible for creating the pty, when
they exit the main pty fd would close and cause cloud-hypervisor to
get I/O errors on writes.

Ideally the main and subordinate pty fds would be kept in the main
vmm's Vm structure. However, because the device manager owns parsing
the configuration for the serial and console devices, the information
is instead stored in new fields under the DeviceManager structure
directly.

From there hooking up the main fd is intended to look as close to
handling stdin and stdout on the tty as possible (there is some future
work ahead for perhaps moving support for the pty into the
vmm_sys_utils crate).

The main fd is used for reading user input and writing to output of
the Vm device. The subordinate fd is used to setup raw mode and it is
kept open in order to avoid I/O errors when clients open and close the
pty device.

The ability to handle multiple inputs as part of this change is
intentional. The current code allows serial and console ptys to be
created and both be used as input. There was an implementation gap
though with the queue_input_bytes needing to be modified so the pty
handlers for serial and console could access the methods on the serial
and console structures directly. Without this change only a single
input source could be processed as the console would switch based on
its input type (this is still valid for tty and isn't otherwise
modified).

Signed-off-by: William Douglas <william.r.douglas@gmail.com>
2021-02-09 10:03:28 +00:00
Rob Bradford
981bb72a09 vmm: api: Add "power-button" API entry point
This will lead to the triggering of an ACPI button inside the guest in
order to cleanly shutdown the guest.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-01-13 17:00:39 +00:00
Rob Bradford
e0d79196c8 virtio-devices, vmm: Enhance debugging around virtio device activation
Sometimes when running under the CI tests fail due to a barrier not
being released and the guest blocks on an MMIO write. Add further
debugging to try and identify the issue.

See: #2118

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2021-01-08 14:06:44 +00:00
Rob Bradford
03db48306b vmm: Activate virtio device from VMM thread
When a device is ready to be activated signal to the VMM thread via an
EventFd that there is a device to be activated. When the VMM receives a
notification on the EventFd that there is a device to be activated
notify the device manager to attempt to activate any devices that have
not been activated.

As a side effect the VMM thread will create the virtio device threads.

Fixes: #1863

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2020-12-17 11:23:53 +00:00
Rob Bradford
280d4fb245 vmm: Include device tree in vm.info API
The DeviceNode cannot be fully represented as it embeds a Rust style
enum (i.e. with data) which is instead represented by a simple
associative array.

Fixes: #1167

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2020-12-01 16:44:25 +01:00
Rob Bradford
b5b97f7b05 vmm: When receiving a migration store the config
The configuration is stored separately to the Vm in the VMM. The failure
to store the config was preventing the VM from shutting down correctly
as Vmm::vm_delete() checks for the presence of the config.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2020-11-25 01:27:26 +01:00
Rob Bradford
df6b52924f vmm: Unlink created socket after source connects
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2020-11-25 01:27:26 +01:00
Rob Bradford
3ac9b6c404 vmm: Implement live migration
Now the VM is paused/resumed by the migration process itself.

0. The guest configuration is sent to the destination
1. Dirty page log tracking is started by start_memory_dirty_log()
2. All guest memory is sent to the destination
3. Up to 5 attempts are made to send the dirty guest memory to the
   destination...
4. ...before the VM is paused
5. One last set of dirty pages is sent to the destination
6. The guest is snapshotted and sent to the destination
7. When the migration is completed the destination unpauses the received
   VM.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2020-11-17 16:57:11 +00:00
Rob Bradford
cf6763dfdb vmm: migration: Add missing response check
A read and check of the response was missing from when sending the
memory to the destination.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2020-11-17 16:57:11 +00:00
Rob Bradford
11a69450ba vm-migration, vmm: Send configuration in separate step
Prior to sending the memory the full state is not needed only the
configuration. This is sufficient to create the appropriate structures
in the guest and have the memory allocations ready for filling.

Update the protocol documentation to add a separate config step and move
the state to after the memory is transferred. As the VM is created in a
separate step to restoring it the requires a slightly different
constructor as well as saving the VM object for the subsequent commands.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2020-11-17 16:57:11 +00:00