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// Copyright 2018 The ChromiumOS Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
mod config;
mod process;
mod vcpu;
use std::fmt::Write as FmtWrite;
use std::fs::File;
use std::io;
use std::io::Read;
use std::io::Write;
use std::os::unix::net::UnixDatagram;
use std::path::Path;
use std::sync::atomic::AtomicBool;
use std::sync::atomic::Ordering;
use std::sync::Arc;
use std::sync::Barrier;
use std::thread;
use std::time::Duration;
use std::time::Instant;
use anyhow::anyhow;
use anyhow::bail;
use anyhow::Context;
use anyhow::Result;
use base::add_fd_flags;
use base::block_signal;
use base::clear_signal;
use base::drop_capabilities;
use base::enable_core_scheduling;
use base::error;
use base::getegid;
use base::geteuid;
use base::info;
use base::pipe;
use base::register_rt_signal_handler;
use base::warn;
use base::AsRawDescriptor;
use base::Error as SysError;
use base::Event;
use base::EventToken;
use base::FromRawDescriptor;
use base::Killable;
use base::MmapError;
use base::RawDescriptor;
use base::Result as SysResult;
use base::SignalFd;
use base::WaitContext;
use base::SIGRTMIN;
use jail::create_sandbox_minijail;
use jail::mount_proc;
use jail::SandboxConfig;
use kvm::Cap;
use kvm::Datamatch;
use kvm::IoeventAddress;
use kvm::Kvm;
use kvm::Vcpu;
use kvm::VcpuExit;
use kvm::Vm;
use libc::c_int;
use libc::c_ulong;
use libc::fcntl;
use libc::ioctl;
use libc::socketpair;
use libc::AF_UNIX;
use libc::EAGAIN;
use libc::EBADF;
use libc::EDEADLK;
use libc::EEXIST;
use libc::EINTR;
use libc::EINVAL;
use libc::ENOENT;
use libc::EOVERFLOW;
use libc::EPERM;
use libc::FIOCLEX;
use libc::F_SETPIPE_SZ;
use libc::O_NONBLOCK;
use libc::SIGCHLD;
use libc::SOCK_SEQPACKET;
use net_util::sys::linux::Tap;
use remain::sorted;
use thiserror::Error;
use vm_memory::GuestMemory;
use vm_memory::MemoryPolicy;
use self::process::*;
use self::vcpu::*;
use crate::crosvm::config::Executable;
use crate::crosvm::config::HypervisorKind;
pub use crate::crosvm::plugin::config::parse_plugin_mount_option;
pub use crate::crosvm::plugin::config::BindMount;
pub use crate::crosvm::plugin::config::GidMap;
use crate::Config;
const MAX_DATAGRAM_SIZE: usize = 4096;
const MAX_VCPU_DATAGRAM_SIZE: usize = 0x40000;
const MAX_OPEN_FILES: u64 = 32768;
/// An error that occurs when communicating with the plugin process.
#[sorted]
#[derive(Error, Debug)]
pub enum CommError {
#[error("failed to decode plugin request: {0}")]
DecodeRequest(protobuf::Error),
#[error("failed to encode plugin response: {0}")]
EncodeResponse(protobuf::Error),
#[error("plugin request socket has been hung up")]
PluginSocketHup,
#[error("failed to recv from plugin request socket: {0}")]
PluginSocketRecv(SysError),
#[error("failed to send to plugin request socket: {0}")]
PluginSocketSend(SysError),
}
fn new_seqpacket_pair() -> SysResult<(UnixDatagram, UnixDatagram)> {
let mut fds = [0, 0];
// SAFETY: trivially safe as we check the return value
unsafe {
let ret = socketpair(AF_UNIX, SOCK_SEQPACKET, 0, fds.as_mut_ptr());
if ret == 0 {
ioctl(fds[0], FIOCLEX);
Ok((
UnixDatagram::from_raw_descriptor(fds[0]),
UnixDatagram::from_raw_descriptor(fds[1]),
))
} else {
Err(SysError::last())
}
}
}
struct VcpuPipe {
crosvm_read: File,
plugin_write: File,
plugin_read: File,
crosvm_write: File,
}
fn new_pipe_pair() -> SysResult<VcpuPipe> {
let to_crosvm = pipe()?;
let to_plugin = pipe()?;
// Increasing the pipe size can be a nice-to-have to make sure that
// messages get across atomically (and made sure that writes don't block),
// though it's not necessary a hard requirement for things to work.
// SAFETY: safe because no memory is modified and we check return value.
let flags = unsafe {
fcntl(
to_crosvm.0.as_raw_descriptor(),
F_SETPIPE_SZ,
MAX_VCPU_DATAGRAM_SIZE as c_int,
)
};
if flags < 0 || flags != MAX_VCPU_DATAGRAM_SIZE as i32 {
warn!(
"Failed to adjust size of crosvm pipe (result {}): {}",
flags,
SysError::last()
);
}
// SAFETY: safe because no memory is modified and we check return value.
let flags = unsafe {
fcntl(
to_plugin.0.as_raw_descriptor(),
F_SETPIPE_SZ,
MAX_VCPU_DATAGRAM_SIZE as c_int,
)
};
if flags < 0 || flags != MAX_VCPU_DATAGRAM_SIZE as i32 {
warn!(
"Failed to adjust size of plugin pipe (result {}): {}",
flags,
SysError::last()
);
}
Ok(VcpuPipe {
crosvm_read: to_crosvm.0,
plugin_write: to_crosvm.1,
plugin_read: to_plugin.0,
crosvm_write: to_plugin.1,
})
}
fn proto_to_sys_err(e: protobuf::Error) -> SysError {
io_to_sys_err(io::Error::from(e))
}
fn io_to_sys_err(e: io::Error) -> SysError {
SysError::new(e.raw_os_error().unwrap_or(EINVAL))
}
fn mmap_to_sys_err(e: MmapError) -> SysError {
match e {
MmapError::SystemCallFailed(e) => e,
_ => SysError::new(EINVAL),
}
}
/// Each `PluginObject` represents one object that was instantiated by the guest using the `Create`
/// request.
///
/// Each such object has an ID associated with it that exists in an ID space shared by every variant
/// of `PluginObject`. This allows all the objects to be indexed in a single map, and allows for a
/// common destroy method.
///
/// In addition to the destory method, each object may have methods specific to its variant type.
/// These variant methods must be done by matching the variant to the expected type for that method.
/// For example, getting the dirty log from a `Memory` object starting with an ID:
///
/// ```ignore
/// match objects.get(&request_id) {
/// Some(&PluginObject::Memory { slot, length }) => vm.get_dirty_log(slot, &mut dirty_log[..]),
/// _ => return Err(SysError::new(ENOENT)),
/// }
/// ```
enum PluginObject {
IoEvent {
evt: Event,
addr: IoeventAddress,
length: u32,
datamatch: u64,
},
Memory {
slot: u32,
length: usize,
},
IrqEvent {
irq_id: u32,
evt: Event,
},
}
impl PluginObject {
fn destroy(self, vm: &mut Vm) -> SysResult<()> {
match self {
PluginObject::IoEvent {
evt,
addr,
length,
datamatch,
} => match length {
0 => vm.unregister_ioevent(&evt, addr, Datamatch::AnyLength),
1 => vm.unregister_ioevent(&evt, addr, Datamatch::U8(Some(datamatch as u8))),
2 => vm.unregister_ioevent(&evt, addr, Datamatch::U16(Some(datamatch as u16))),
4 => vm.unregister_ioevent(&evt, addr, Datamatch::U32(Some(datamatch as u32))),
8 => vm.unregister_ioevent(&evt, addr, Datamatch::U64(Some(datamatch))),
_ => Err(SysError::new(EINVAL)),
},
PluginObject::Memory { slot, .. } => vm.remove_memory_region(slot).and(Ok(())),
PluginObject::IrqEvent { irq_id, evt } => vm.unregister_irqfd(&evt, irq_id),
}
}
}
pub fn run_vcpus(
kvm: &Kvm,
vm: &Vm,
plugin: &Process,
vcpu_count: u32,
kill_signaled: &Arc<AtomicBool>,
exit_evt: &Event,
vcpu_handles: &mut Vec<thread::JoinHandle<()>>,
vcpu_cgroup_tasks_file: Option<File>,
) -> Result<()> {
let vcpu_thread_barrier = Arc::new(Barrier::new((vcpu_count) as usize));
let use_kvm_signals = !kvm.check_extension(Cap::ImmediateExit);
// If we need to force a vcpu to exit from a VM then a SIGRTMIN signal is sent
// to that vcpu's thread. If KVM is running the VM then it'll return -EINTR.
// An issue is what to do when KVM isn't running the VM (where we could be
// in the kernel or in the app).
//
// If KVM supports "immediate exit" then we set a signal handler that will
// set the |immediate_exit| flag that tells KVM to return -EINTR before running
// the VM.
//
// If KVM doesn't support immediate exit then we'll block SIGRTMIN in the app
// and tell KVM to unblock SIGRTMIN before running the VM (at which point a blocked
// signal might get asserted). There's overhead to have KVM unblock and re-block
// SIGRTMIN each time it runs the VM, so this mode should be avoided.
if use_kvm_signals {
// SAFETY:
// Our signal handler does nothing and is trivially async signal safe.
unsafe {
extern "C" fn handle_signal(_: c_int) {}
// We need to install this signal handler even though we do block
// the signal below, to ensure that this signal will interrupt
// execution of KVM_RUN (this is implementation issue).
register_rt_signal_handler(SIGRTMIN() + 0, handle_signal)
.expect("failed to register vcpu signal handler");
}
// We do not really want the signal handler to run...
block_signal(SIGRTMIN() + 0).expect("failed to block signal");
} else {
// SAFETY: trivially safe as we check return value.
unsafe {
extern "C" fn handle_signal(_: c_int) {
Vcpu::set_local_immediate_exit(true);
}
register_rt_signal_handler(SIGRTMIN() + 0, handle_signal)
.expect("failed to register vcpu signal handler");
}
}
for cpu_id in 0..vcpu_count {
let kill_signaled = kill_signaled.clone();
let vcpu_thread_barrier = vcpu_thread_barrier.clone();
let vcpu_exit_evt = exit_evt.try_clone().context("failed to clone event")?;
let vcpu_plugin = plugin.create_vcpu(cpu_id)?;
let vcpu = Vcpu::new(cpu_id as c_ulong, kvm, vm).context("error creating vcpu")?;
let vcpu_cgroup_tasks_file = vcpu_cgroup_tasks_file
.as_ref()
.map(|f| f.try_clone().unwrap());
vcpu_handles.push(
thread::Builder::new()
.name(format!("crosvm_vcpu{}", cpu_id))
.spawn(move || {
if use_kvm_signals {
// Tell KVM to not block anything when entering kvm run
// because we will be using first RT signal to kick the VCPU.
vcpu.set_signal_mask(&[])
.expect("failed to set up KVM VCPU signal mask");
}
// Move vcpu thread to cgroup
if let Some(mut f) = vcpu_cgroup_tasks_file {
f.write_all(base::gettid().to_string().as_bytes()).unwrap();
}
if let Err(e) = enable_core_scheduling() {
error!("Failed to enable core scheduling: {}", e);
}
let vcpu = vcpu
.to_runnable(Some(SIGRTMIN() + 0))
.expect("Failed to set thread id");
let res = vcpu_plugin.init(&vcpu);
vcpu_thread_barrier.wait();
if let Err(e) = res {
error!("failed to initialize vcpu {}: {}", cpu_id, e);
} else {
loop {
let mut interrupted_by_signal = false;
let run_res = vcpu.run();
match run_res {
Ok(run) => match run {
VcpuExit::IoIn { port, mut size } => {
let mut data = [0; 256];
if size > data.len() {
error!(
"unsupported IoIn size of {} bytes at port {:#x}",
size, port
);
size = data.len();
}
vcpu_plugin.io_read(port as u64, &mut data[..size], &vcpu);
if let Err(e) = vcpu.set_data(&data[..size]) {
error!(
"failed to set return data for IoIn at port {:#x}: {}",
port, e
);
}
}
VcpuExit::IoOut {
port,
mut size,
data,
} => {
if size > data.len() {
error!("unsupported IoOut size of {} bytes at port {:#x}", size, port);
size = data.len();
}
vcpu_plugin.io_write(port as u64, &data[..size], &vcpu);
}
VcpuExit::MmioRead { address, size } => {
let mut data = [0; 8];
vcpu_plugin.mmio_read(
address,
&mut data[..size],
&vcpu,
);
// Setting data for mmio can not fail.
let _ = vcpu.set_data(&data[..size]);
}
VcpuExit::MmioWrite {
address,
size,
data,
} => {
vcpu_plugin.mmio_write(
address,
&data[..size],
&vcpu,
);
}
VcpuExit::HypervHcall { input, params } => {
let mut data = [0; 8];
vcpu_plugin.hyperv_call(input, params, &mut data, &vcpu);
// Setting data for hyperv call can not fail.
let _ = vcpu.set_data(&data);
}
VcpuExit::HypervSynic {
msr,
control,
evt_page,
msg_page,
} => {
vcpu_plugin
.hyperv_synic(msr, control, evt_page, msg_page, &vcpu);
}
VcpuExit::Hlt => break,
VcpuExit::Shutdown => break,
VcpuExit::InternalError => {
error!("vcpu {} has internal error", cpu_id);
break;
}
r => warn!("unexpected vcpu exit: {:?}", r),
},
Err(e) => match e.errno() {
EINTR => interrupted_by_signal = true,
EAGAIN => {}
_ => {
error!("vcpu hit unknown error: {}", e);
break;
}
},
}
if kill_signaled.load(Ordering::SeqCst) {
break;
}
// Only handle the pause request if kvm reported that it was
// interrupted by a signal. This helps to entire that KVM has had a chance
// to finish emulating any IO that may have immediately happened.
// If we eagerly check pre_run() then any IO that we
// just reported to the plugin won't have been processed yet by KVM.
// Not eagerly calling pre_run() also helps to reduce
// any overhead from checking if a pause request is pending.
// The assumption is that pause requests aren't common
// or frequent so it's better to optimize for the non-pause execution paths.
if interrupted_by_signal {
if use_kvm_signals {
clear_signal(SIGRTMIN() + 0)
.expect("failed to clear pending signal");
} else {
vcpu.set_immediate_exit(false);
}
if let Err(e) = vcpu_plugin.pre_run(&vcpu) {
error!("failed to process pause on vcpu {}: {}", cpu_id, e);
break;
}
}
}
}
vcpu_exit_evt
.signal()
.expect("failed to signal vcpu exit event");
})
.context("error spawning vcpu thread")?,
);
}
Ok(())
}
#[derive(EventToken)]
enum Token {
Exit,
ChildSignal,
Stderr,
Plugin { index: usize },
}
/// Run a VM with a plugin process specified by `cfg`.
///
/// Not every field of `cfg` will be used. In particular, most field that pertain to a specific
/// device are ignored because the plugin is responsible for emulating hardware.
pub fn run_config(cfg: Config) -> Result<()> {
info!("crosvm starting plugin process");
// Masking signals is inherently dangerous, since this can persist across clones/execs. Do this
// before any jailed devices have been spawned, so that we can catch any of them that fail very
// quickly.
let sigchld_fd = SignalFd::new(SIGCHLD).context("failed to create signalfd")?;
// Create a pipe to capture error messages from plugin and minijail.
let (mut stderr_rd, stderr_wr) = pipe().context("failed to create stderr pipe")?;
add_fd_flags(stderr_rd.as_raw_descriptor(), O_NONBLOCK)
.context("error marking stderr nonblocking")?;
let jail = if let Some(jail_config) = cfg.jail_config.as_ref() {
if jail_config.seccomp_policy_dir.is_none() {
bail!("plugin requires seccomp policy file specified.");
}
let mut config = SandboxConfig::new(jail_config, "plugin");
config.bind_mounts = true;
let uid_map = format!("0 {} 1", geteuid());
let gid_map = format!("0 {} 1", getegid());
let gid_map = if !cfg.plugin_gid_maps.is_empty() {
gid_map
+ &cfg
.plugin_gid_maps
.into_iter()
.fold(String::new(), |mut output, m| {
let _ = write!(output, ",{} {} {}", m.inner, m.outer, m.count);
output
})
} else {
gid_map
};
config.ugid_map = Some((&uid_map, &gid_map));
let root_path = cfg.plugin_root.as_ref().unwrap_or(&jail_config.pivot_root);
let mut jail = create_sandbox_minijail(root_path, MAX_OPEN_FILES, &config)
.context("create plugin sandbox")?;
// Because we requested to "run as init", minijail will not mount /proc for us even though
// plugin will be running in its own PID namespace, so we have to mount it ourselves.
mount_proc(&mut jail).context("mount proc")?;
// Mount minimal set of devices (full, zero, urandom, etc). We can not use
// jail.mount_dev() here because crosvm may not be running with CAP_SYS_ADMIN.
let device_names = ["full", "null", "urandom", "zero"];
for name in &device_names {
let device = Path::new("/dev").join(name);
jail.mount_bind(&device, &device, true)
.context("failed to mount dev")?;
}
for bind_mount in &cfg.plugin_mounts {
jail.mount_bind(&bind_mount.src, &bind_mount.dst, bind_mount.writable)
.with_context(|| {
format!(
"failed to bind mount {} -> {} as {} ",
bind_mount.src.display(),
bind_mount.dst.display(),
if bind_mount.writable {
"writable"
} else {
"read only"
}
)
})?;
}
Some(jail)
} else {
None
};
#[allow(unused_mut)]
let mut tap_interfaces: Vec<Tap> = Vec::new();
#[cfg(feature = "net")]
for net_params in cfg.net {
use devices::virtio::NetParametersMode;
use net_util::TapTCommon;
if net_params.vhost_net.is_some() {
bail!("vhost-net not supported with plugin");
}
match net_params.mode {
NetParametersMode::RawConfig {
host_ip,
netmask,
mac,
} => {
let tap = Tap::new(false, false).context("error opening tap device")?;
tap.set_ip_addr(host_ip).context("error setting tap ip")?;
tap.set_netmask(netmask)
.context("error setting tap netmask")?;
tap.set_mac_address(mac)
.context("error setting tap mac address")?;
tap.enable().context("error enabling tap device")?;
tap_interfaces.push(tap);
}
NetParametersMode::TapName { tap_name, mac } => {
let tap = Tap::new_with_name(tap_name.as_bytes(), true, false)
.context("failed to create tap device from name")?;
if let Some(mac) = mac {
tap.set_mac_address(mac)
.context("error setting tap mac addres")?;
}
tap_interfaces.push(tap);
}
NetParametersMode::TapFd { tap_fd, mac } => {
// SAFETY:
// Safe because we ensure that we get a unique handle to the fd.
let tap = unsafe {
Tap::from_raw_descriptor(
base::validate_raw_descriptor(tap_fd)
.context("failed to validate raw tap fd")?,
)
.context("failed to create tap device from raw fd")?
};
if let Some(mac) = mac {
tap.set_mac_address(mac)
.context("error setting tap mac addres")?;
}
tap_interfaces.push(tap);
}
}
}
let plugin_args: Vec<&str> = cfg.params.iter().map(|s| &s[..]).collect();
let plugin_path = match cfg.executable_path {
Some(Executable::Plugin(ref plugin_path)) => plugin_path.as_path(),
_ => panic!("Executable was not a plugin"),
};
let vcpu_count = cfg.vcpu_count.unwrap_or(1) as u32;
let mut mem = GuestMemory::new(&[]).unwrap();
let mut mem_policy = MemoryPolicy::empty();
if cfg.hugepages {
mem_policy |= MemoryPolicy::USE_HUGEPAGES;
}
mem.set_memory_policy(mem_policy);
let kvm_device_path = if let Some(HypervisorKind::Kvm { device }) = &cfg.hypervisor {
device.as_deref()
} else {
None
};
let kvm_device_path = kvm_device_path.unwrap_or(Path::new("/dev/kvm"));
let kvm = Kvm::new_with_path(kvm_device_path).context("error creating Kvm")?;
let mut vm = Vm::new(&kvm, mem).context("error creating vm")?;
vm.create_irq_chip()
.context("failed to create kvm irqchip")?;
vm.create_pit().context("failed to create kvm PIT")?;
let mut plugin = Process::new(vcpu_count, plugin_path, &plugin_args, jail, stderr_wr)?;
// Now that the jail for the plugin has been created and we had a chance to adjust gids there,
// we can drop all our capabilities in case we had any.
drop_capabilities().context("failed to drop process capabilities")?;
let mut res = Ok(());
// If Some, we will exit after enough time is passed to shutdown cleanly.
let mut dying_instant: Option<Instant> = None;
let duration_to_die = Duration::from_millis(1000);
let exit_evt = Event::new().context("failed to create event")?;
let kill_signaled = Arc::new(AtomicBool::new(false));
let mut vcpu_handles = Vec::with_capacity(vcpu_count as usize);
let wait_ctx = WaitContext::build_with(&[
(&exit_evt, Token::Exit),
(&sigchld_fd, Token::ChildSignal),
(&stderr_rd, Token::Stderr),
])
.context("failed to add control descriptors to wait context")?;
let mut sockets_to_drop = Vec::new();
let mut redo_wait_ctx_sockets = true;
// In this loop, make every attempt to not return early. If an error is encountered, set `res`
// to the error, set `dying_instant` to now, and signal the plugin that it will be killed soon.
// If the plugin cannot be signaled because it is dead of `signal_kill` failed, simply break
// from the poll loop so that the VCPU threads can be cleaned up.
'wait: loop {
// After we have waited long enough, it's time to give up and exit.
if dying_instant
.map(|i| i.elapsed() >= duration_to_die)
.unwrap_or(false)
{
break;
}
if redo_wait_ctx_sockets {
for (index, socket) in plugin.sockets().iter().enumerate() {
wait_ctx
.add(socket, Token::Plugin { index })
.context("failed to add plugin sockets to wait context")?;
}
}
let plugin_socket_count = plugin.sockets().len();
let events = {
let poll_res = match dying_instant {
Some(inst) => wait_ctx.wait_timeout(duration_to_die - inst.elapsed()),
None => wait_ctx.wait(),
};
match poll_res {
Ok(v) => v,
Err(e) => {
// Polling no longer works, time to break and cleanup,
if res.is_ok() {
res = Err(e).context("failed to poll all FDs");
}
break;
}
}
};
for event in events.iter().filter(|e| e.is_hungup) {
if let Token::Stderr = event.token {
let _ = wait_ctx.delete(&stderr_rd);
}
}
for event in events.iter().filter(|e| e.is_readable) {
match event.token {
Token::Exit => {
// No need to check the exit event if we are already doing cleanup.
let _ = wait_ctx.delete(&exit_evt);
dying_instant.get_or_insert(Instant::now());
let sig_res = plugin.signal_kill();
if res.is_ok() && sig_res.is_err() {
res = sig_res.context("error sending kill signal to plugin on exit event");
}
}
Token::ChildSignal => {
// Print all available siginfo structs, then exit the loop.
loop {
match sigchld_fd.read() {
Ok(Some(siginfo)) => {
// If the plugin process has ended, there is no need to continue
// processing plugin connections, so we break early.
if siginfo.ssi_pid == plugin.pid() as u32 {
break 'wait;
}
// Because SIGCHLD is not expected from anything other than the
// plugin process, report it as an error.
if res.is_ok() {
res = Err(anyhow!(
"process {} died with signal {}, status {}, and code {}",
siginfo.ssi_pid,
siginfo.ssi_signo,
siginfo.ssi_status,
siginfo.ssi_code,
));
}
}
Ok(None) => break, // No more signals to read.
Err(e) => {
// Something really must be messed up for this to happen, continue
// processing connections for a limited time.
if res.is_ok() {
res = Err(e).context("failed to read signal fd");
}
break;
}
}
}
// As we only spawn the plugin process, getting a SIGCHLD can only mean
// something went wrong.
dying_instant.get_or_insert(Instant::now());
let sig_res = plugin.signal_kill();
if res.is_ok() && sig_res.is_err() {
res = sig_res.context("error sending kill signal to plugin on SIGCHLD");
}
}
Token::Stderr => loop {
let mut buf = [0u8; 4096];
match stderr_rd.read(&mut buf) {
Ok(len) => {
for l in String::from_utf8_lossy(&buf[0..len]).lines() {
error!("minijail/plugin: {}", l);
}
}
Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
break;
}
Err(e) => {
error!("failed reading from stderr: {}", e);
break;
}
}
},
Token::Plugin { index } => {
match plugin.handle_socket(index, &kvm, &mut vm, &vcpu_handles, &tap_interfaces)
{
Ok(_) => {}
// A HUP is an expected event for a socket, so don't bother warning about
// it.
Err(CommError::PluginSocketHup) => sockets_to_drop.push(index),
// Only one connection out of potentially many is broken. Drop it, but don't
// start cleaning up. Because the error isn't returned, we will warn about
// it here.
Err(e) => {
warn!("error handling plugin socket: {}", e);
sockets_to_drop.push(index);
}
}
}
}
}
if vcpu_handles.is_empty() && dying_instant.is_none() && plugin.is_started() {
let vcpu_cgroup_tasks_file = match &cfg.vcpu_cgroup_path {
None => None,
Some(cgroup_path) => {
// Move main process to cgroup_path
let mut f = File::create(cgroup_path.join("tasks"))?;
f.write_all(std::process::id().to_string().as_bytes())?;
Some(f)
}
};
let res = run_vcpus(
&kvm,
&vm,
&plugin,
vcpu_count,
&kill_signaled,
&exit_evt,
&mut vcpu_handles,
vcpu_cgroup_tasks_file,
);
if let Err(e) = res {
dying_instant.get_or_insert(Instant::now());
error!("failed to start vcpus: {}", e);
}
}
redo_wait_ctx_sockets =
!sockets_to_drop.is_empty() || plugin.sockets().len() != plugin_socket_count;
// Cleanup all of the sockets that we have determined were disconnected or suffered some
// other error.
plugin.drop_sockets(&mut sockets_to_drop);
sockets_to_drop.clear();
if redo_wait_ctx_sockets {
for socket in plugin.sockets() {
let _ = wait_ctx.delete(socket);
}
}
}
// vcpu threads MUST see the kill signaled flag, otherwise they may re-enter the VM.
kill_signaled.store(true, Ordering::SeqCst);
// Depending on how we ended up here, the plugin process, or a VCPU thread waiting for requests
// might be stuck. The `signal_kill` call will unstick all the VCPU threads by closing their
// blocked connections.
plugin
.signal_kill()
.context("error sending kill signal to plugin on cleanup")?;
for handle in vcpu_handles {
match handle.kill(SIGRTMIN() + 0) {
Ok(_) => {
if let Err(e) = handle.join() {
error!("failed to join vcpu thread: {:?}", e);
}
}
Err(e) => error!("failed to kill vcpu thread: {}", e),
}
}
match plugin.try_wait() {
// The plugin has run out of time by now
Ok(ProcessStatus::Running) => Err(anyhow!("plugin did not exit within timeout")),
// Return an error discovered earlier in this function.
Ok(ProcessStatus::Success) => res.map_err(anyhow::Error::msg),
Ok(ProcessStatus::Fail(code)) => Err(anyhow!("plugin exited with error: {}", code)),
Ok(ProcessStatus::Signal(code)) => Err(anyhow!("plugin exited with signal {}", code)),
Err(e) => Err(anyhow!("error waiting for plugin to exit: {}", e)),
}
}