vmspawn: added vsock functionality

also includes cosmetic fixups from: https://github.com/systemd/systemd/pull/29874

src/vmspawn/vmspawn-util.c

@@ -1,9 +1,9 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
-#include <stdio.h>
 #include <unistd.h>
+#include <linux/vhost.h>
+#include <sys/ioctl.h>
 
-#include "alloc-util.h"
 #include "architecture.h"
 #include "conf-files.h"
 #include "errno-util.h"
@@ -15,7 +15,10 @@
 #include "memory-util.h"
 #include "path-lookup.h"
 #include "path-util.h"
+#include "random-util.h"
 #include "recurse-dir.h"
+#include "siphash24.h"
+#include "socket-util.h"
 #include "sort-util.h"
 #include "string-util.h"
 #include "strv.h"
@@ -45,6 +48,32 @@ int qemu_check_kvm_support(void) {
         return -errno;
 }
 
+int qemu_check_vsock_support(void) {
+        _cleanup_close_ int fd = -EBADF;
+        /* Just using access() will just check if the device node exists, but not whether a
+         * device driver is behind it (this is a common case since systemd-tmpfiles creates
+         * the device node on boot, typically).
+         *
+         * Hence we open() the path to see if there's actually something behind.
+         *
+         * If not this should return ENODEV.
+         */
+
+        fd = open("/dev/vhost-vsock", O_RDWR|O_CLOEXEC);
+        if (fd >= 0)
+                return true;
+        if (errno == ENODEV) {
+                log_debug_errno(errno, "/dev/vhost-vsock device doesn't exist. Not adding a vsock device to the virtual machine.");
+                return false;
+        }
+        if (errno == EPERM) {
+                log_debug_errno(errno, "Permission denied to access /dev/vhost-vsock. Not adding a vsock device to the virtual machine.");
+                return false;
+        }
+
+        return -errno;
+}
+
 /* holds the data retrieved from the QEMU firmware interop JSON data */
 typedef struct FirmwareData {
         char **features;
@@ -237,3 +266,79 @@ int find_qemu_binary(char **ret_qemu_binary) {
 
         return find_executable(qemu_arch_specific, ret_qemu_binary);
 }
+
+int vsock_fix_child_cid(unsigned *machine_cid, const char *machine, int *ret_child_sock) {
+        /* this is an arbitrary value picked from /dev/urandom */
+        static const uint8_t sip_key[HASH_KEY_SIZE] = {
+                0x03, 0xad, 0xf0, 0xa4,
+                0x59, 0x2c, 0x77, 0x11,
+                0xda, 0x39, 0x0c, 0xba,
+                0xf5, 0x4c, 0x80, 0x52
+        };
+        struct siphash machine_hash_state, state;
+        _cleanup_close_ int vfd = -EBADF;
+        int r;
+
+        /* uint64_t is required here for the ioctl call, but valid CIDs are only 32 bits */
+        uint64_t cid = *ASSERT_PTR(machine_cid);
+
+        assert(machine);
+        assert(ret_child_sock);
+
+        /* Fix the CID of the AF_VSOCK socket passed to qemu
+         *
+         * If the user has passed us a CID (machine_cid != VMADDR_CID_ANY), then attempt to bind to that CID
+         * and error if we cannot.
+         *
+         * Otherwise hash the machine name to get a random CID and attempt to bind to that.
+         * If it is occupied add more information into the hash and try again.
+         * If after 64 attempts this hasn't worked fallback to truly random CIDs.
+         * If after another 64 attempts this hasn't worked then give up and return EADDRNOTAVAIL.
+         */
+
+        /* remove O_CLOEXEC before this fd is passed to QEMU */
+        vfd = open("/dev/vhost-vsock", O_RDWR|O_CLOEXEC);
+        if (vfd < 0)
+                return log_debug_errno(errno, "Failed to open /dev/vhost-vsock as read/write: %m");
+
+        if (cid != VMADDR_CID_ANY) {
+                r = ioctl(vfd, VHOST_VSOCK_SET_GUEST_CID, &cid);
+                if (r < 0)
+                        return log_debug_errno(errno, "Failed to set CID for child vsock with user provided CID %" PRIu64 ": %m", cid);
+                *ret_child_sock = TAKE_FD(vfd);
+                return 0;
+        }
+
+        siphash24_init(&machine_hash_state, sip_key);
+        siphash24_compress_string(machine, &machine_hash_state);
+        for (unsigned i = 0; i < 64; i++) {
+                state = machine_hash_state;
+                siphash24_compress_safe(&i, sizeof i, &state);
+                uint64_t hash = siphash24_finalize(&state);
+
+                cid = 3 + (hash % (UINT_MAX - 4));
+                r = ioctl(vfd, VHOST_VSOCK_SET_GUEST_CID, &cid);
+                if (r >= 0) {
+                        *machine_cid = cid;
+                        *ret_child_sock = TAKE_FD(vfd);
+                        return 0;
+                }
+                if (errno != EADDRINUSE)
+                        return -errno;
+        }
+
+        for (unsigned i = 0; i < 64; i++) {
+                cid = 3 + random_u64_range(UINT_MAX - 4);
+                r = ioctl(vfd, VHOST_VSOCK_SET_GUEST_CID, &cid);
+                if (r >= 0) {
+                        *machine_cid = cid;
+                        *ret_child_sock = TAKE_FD(vfd);
+                        return 0;
+                }
+
+                if (errno != EADDRINUSE)
+                        return -errno;
+        }
+
+        return log_debug_errno(SYNTHETIC_ERRNO(EADDRNOTAVAIL), "Failed to assign a CID to the guest vsock");
+}

src/vmspawn/vmspawn-util.h

@@ -20,5 +20,7 @@ OvmfConfig* ovmf_config_free(OvmfConfig *ovmf_config);
 DEFINE_TRIVIAL_CLEANUP_FUNC(OvmfConfig*, ovmf_config_free);
 
 int qemu_check_kvm_support(void);
+int qemu_check_vsock_support(void);
 int find_ovmf_config(int search_sb, OvmfConfig **ret_ovmf_config);
 int find_qemu_binary(char **ret_qemu_binary);
+int vsock_fix_child_cid(unsigned *machine_cid, const char *machine, int *ret_child_sock);

src/vmspawn/vmspawn.c

@@ -9,12 +9,15 @@
 #include "alloc-util.h"
 #include "architecture.h"
 #include "build.h"
+#include "common-signal.h"
 #include "copy.h"
 #include "creds-util.h"
 #include "escape.h"
 #include "fileio.h"
 #include "format-util.h"
+#include "fs-util.h"
 #include "hexdecoct.h"
+#include "hostname-util.h"
 #include "log.h"
 #include "machine-credential.h"
 #include "main-func.h"
@@ -24,6 +27,9 @@
 #include "path-util.h"
 #include "pretty-print.h"
 #include "process-util.h"
+#include "sd-event.h"
+#include "signal-util.h"
+#include "socket-util.h"
 #include "strv.h"
 #include "tmpfile-util.h"
 #include "vmspawn-settings.h"
@@ -31,9 +37,12 @@
 
 static PagerFlags arg_pager_flags = 0;
 static char *arg_image = NULL;
+static char *arg_machine = NULL;
 static char *arg_qemu_smp = NULL;
 static uint64_t arg_qemu_mem = 2ULL * 1024ULL * 1024ULL * 1024ULL;
 static int arg_qemu_kvm = -1;
+static int arg_qemu_vsock = -1;
+static uint64_t arg_vsock_cid = UINT64_MAX;
 static bool arg_qemu_gui = false;
 static int arg_secure_boot = -1;
 static MachineCredential *arg_credentials = NULL;
@@ -42,6 +51,7 @@ static SettingsMask arg_settings_mask = 0;
 static char **arg_parameters = NULL;
 
 STATIC_DESTRUCTOR_REGISTER(arg_image, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_machine, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_qemu_smp, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_parameters, strv_freep);
 
@@ -66,9 +76,14 @@ static int help(void) {
                "%3$sHost Configuration:%4$s\n"
                "     --qemu-smp=SMP         Configure guest's SMP settings\n"
                "     --qemu-mem=MEM         Configure guest's RAM size\n"
-               "     --qemu-kvm=            Configure whether to use KVM or not\n"
+               "     --qemu-kvm=BOOL        Configure whether to use KVM or not\n"
+               "     --qemu-vsock=BOOL      Configure whether to use qemu with a vsock or not\n"
+               "     --vsock-cid=           Specify the CID to use for the qemu guest's vsock\n"
                "     --qemu-gui             Start QEMU in graphical mode\n"
-               "     --secure-boot=         Configure searching for firmware with SB support\n\n"
+               "     --secure-boot=BOOL     Configure whether to search for firmware which\n"
+               "                            supports Secure Boot\n\n"
+               "%3$sSystem Identity:%4$s\n"
+               "  -M --machine=NAME         Set the machine name for the container\n"
                "%3$sCredentials:%4$s\n"
                "     --set-credential=ID:VALUE\n"
                "                            Pass a credential with literal value to container.\n"
@@ -93,6 +108,8 @@ static int parse_argv(int argc, char *argv[]) {
                 ARG_QEMU_SMP,
                 ARG_QEMU_MEM,
                 ARG_QEMU_KVM,
+                ARG_QEMU_VSOCK,
+                ARG_VSOCK_CID,
                 ARG_QEMU_GUI,
                 ARG_SECURE_BOOT,
                 ARG_SET_CREDENTIAL,
@@ -104,9 +121,12 @@ static int parse_argv(int argc, char *argv[]) {
                 { "version",         no_argument,       NULL, ARG_VERSION         },
                 { "no-pager",        no_argument,       NULL, ARG_NO_PAGER        },
                 { "image",           required_argument, NULL, 'i'                 },
+                { "machine",         required_argument, NULL, 'M'                 },
                 { "qemu-smp",        required_argument, NULL, ARG_QEMU_SMP        },
                 { "qemu-mem",        required_argument, NULL, ARG_QEMU_MEM        },
                 { "qemu-kvm",        required_argument, NULL, ARG_QEMU_KVM        },
+                { "qemu-vsock",      required_argument, NULL, ARG_QEMU_VSOCK      },
+                { "vsock-cid",       required_argument, NULL, ARG_VSOCK_CID       },
                 { "qemu-gui",        no_argument,       NULL, ARG_QEMU_GUI        },
                 { "secure-boot",     required_argument, NULL, ARG_SECURE_BOOT     },
                 { "set-credential",  required_argument, NULL, ARG_SET_CREDENTIAL  },
@@ -120,7 +140,7 @@ static int parse_argv(int argc, char *argv[]) {
         assert(argv);
 
         optind = 0;
-        while ((c = getopt_long(argc, argv, "+hi:", options, NULL)) >= 0)
+        while ((c = getopt_long(argc, argv, "+hi:M", options, NULL)) >= 0)
                 switch (c) {
                 case 'h':
                         return help();
@@ -136,6 +156,20 @@ static int parse_argv(int argc, char *argv[]) {
                         arg_settings_mask |= SETTING_DIRECTORY;
                         break;
 
+                case 'M':
+                        if (isempty(optarg))
+                                arg_machine = mfree(arg_machine);
+                        else {
+                                if (!hostname_is_valid(optarg, 0))
+                                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                                               "Invalid machine name: %s", optarg);
+
+                                r = free_and_strdup(&arg_machine, optarg);
+                                if (r < 0)
+                                        return log_oom();
+                        }
+                        break;
+
                 case ARG_NO_PAGER:
                         arg_pager_flags |= PAGER_DISABLE;
                         break;
@@ -158,6 +192,27 @@ static int parse_argv(int argc, char *argv[]) {
                             return log_error_errno(r, "Failed to parse --qemu-kvm=%s: %m", optarg);
                         break;
 
+                case ARG_QEMU_VSOCK:
+                        r = parse_tristate(optarg, &arg_qemu_vsock);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to parse --qemu-vsock=%s: %m", optarg);
+                        break;
+
+                case ARG_VSOCK_CID: {
+                        unsigned cid;
+                        if (isempty(optarg))
+                                cid = VMADDR_CID_ANY;
+                        else {
+                                r = safe_atou_bounded(optarg, 3, UINT_MAX - 1, &cid);
+                                if (r == -ERANGE)
+                                        return log_error_errno(r, "Invalid value for --vsock-cid=: %m");
+                                if (r < 0)
+                                        return log_error_errno(r, "Failed to parse --vsock-cid=%s: %m", optarg);
+                        }
+                        arg_vsock_cid = (uint64_t)cid;
+                        break;
+                }
+
                 case ARG_QEMU_GUI:
                         arg_qemu_gui = true;
                         break;
@@ -208,11 +263,187 @@ static int parse_argv(int argc, char *argv[]) {
         return 1;
 }
 
+static int open_vsock(void) {
+        _cleanup_close_ int vsock_fd = -EBADF;
+        int r;
+        static const union sockaddr_union bind_addr = {
+                .vm.svm_family = AF_VSOCK,
+                .vm.svm_cid = VMADDR_CID_ANY,
+                .vm.svm_port = VMADDR_PORT_ANY,
+        };
+
+        vsock_fd = socket(AF_VSOCK, SOCK_STREAM|SOCK_CLOEXEC, 0);
+        if (vsock_fd < 0)
+                return log_error_errno(errno, "Failed to open AF_VSOCK socket: %m");
+
+        r = bind(vsock_fd, &bind_addr.sa, sizeof(bind_addr.vm));
+        if (r < 0)
+                return log_error_errno(errno, "Failed to bind to vsock to address %u:%u: %m", bind_addr.vm.svm_cid, bind_addr.vm.svm_port);
+
+        r = listen(vsock_fd, SOMAXCONN_DELUXE);
+        if (r < 0)
+                return log_error_errno(errno, "Failed to listen on vsock: %m");
+
+        return TAKE_FD(vsock_fd);
+}
+
+static int vmspawn_dispatch_notify_fd(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
+        char buf[NOTIFY_BUFFER_MAX+1];
+        const char *p = NULL;
+        struct iovec iovec = {
+                .iov_base = buf,
+                .iov_len = sizeof(buf)-1,
+        };
+        struct msghdr msghdr = {
+                .msg_iov = &iovec,
+                .msg_iovlen = 1,
+        };
+        ssize_t n;
+        _cleanup_strv_free_ char **tags = NULL;
+        int r, *exit_status = ASSERT_PTR(userdata);
+
+        n = recvmsg_safe(fd, &msghdr, MSG_DONTWAIT);
+        if (ERRNO_IS_NEG_TRANSIENT(n))
+                return 0;
+        if (n == -EXFULL) {
+                log_warning_errno(n, "Got message with truncated control data, ignoring: %m");
+                return 0;
+        }
+        if (n < 0)
+                return log_warning_errno(n, "Couldn't read notification socket: %m");
+
+        if ((size_t) n >= sizeof(buf)) {
+                log_warning("Received notify message exceeded maximum size. Ignoring.");
+                return 0;
+        }
+
+        buf[n] = 0;
+        tags = strv_split(buf, "\n\r");
+        if (!tags)
+                return log_oom();
+
+        STRV_FOREACH(s, tags)
+                log_debug("Received tag %s from notify socket", *s);
+
+        if (strv_contains(tags, "READY=1")) {
+                r = sd_notify(false, "READY=1\n");
+                if (r < 0)
+                        log_warning_errno(r, "Failed to send readiness notification, ignoring: %m");
+        }
+
+        p = strv_find_startswith(tags, "STATUS=");
+        if (p)
+                (void) sd_notifyf(false, "STATUS=VM running: %s", p);
+
+        p = strv_find_startswith(tags, "EXIT_STATUS=");
+        if (p) {
+                r = safe_atoi(p, exit_status);
+                if (r < 0)
+                        log_warning_errno(r, "Failed to parse exit status from %s, ignoring: %m", p);
+        }
+
+        /* we will only receive one message from each connection so disable this source once one is received */
+        source = sd_event_source_disable_unref(source);
+
+        return 0;
+}
+
+static int vmspawn_dispatch_vsock_connections(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
+        int r;
+        sd_event *event;
+        _cleanup_close_ int conn_fd = -EBADF;
+
+        assert(userdata);
+
+        if (revents != EPOLLIN) {
+                log_warning("Got unexpected poll event for vsock fd.");
+                return 0;
+        }
+
+        conn_fd = accept4(fd, NULL, NULL, SOCK_CLOEXEC|SOCK_NONBLOCK);
+        if (conn_fd < 0) {
+                log_warning_errno(errno, "Failed to accept connection from vsock fd (%m), ignoring...");
+                return 0;
+        }
+
+        event = sd_event_source_get_event(source);
+        if (!event)
+                return log_error_errno(SYNTHETIC_ERRNO(ENOENT), "Failed to retrieve event from event source, exiting task");
+
+        /* add a new floating task to read from the connection */
+        r = sd_event_add_io(event, NULL, conn_fd, revents, vmspawn_dispatch_notify_fd, userdata);
+        if (r < 0)
+                return log_error_errno(r, "Failed to allocate notify connection event source: %m");
+
+        /* conn_fd is now owned by the event loop so don't clean it up */
+        TAKE_FD(conn_fd);
+
+        return 0;
+}
+
+static int setup_notify_parent(sd_event *event, int fd, int *exit_status, sd_event_source **notify_event_source) {
+        int r;
+
+        r = sd_event_add_io(event, notify_event_source, fd, EPOLLIN, vmspawn_dispatch_vsock_connections, exit_status);
+        if (r < 0)
+                return log_error_errno(r, "Failed to allocate notify socket event source: %m");
+
+        (void) sd_event_source_set_description(*notify_event_source, "vmspawn-notify-sock");
+
+        return 0;
+}
+
+static int on_orderly_shutdown(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
+        pid_t pid;
+
+        pid = PTR_TO_PID(userdata);
+        if (pid > 0) {
+                /* TODO: actually talk to qemu and ask the guest to shutdown here */
+                if (kill(pid, SIGKILL) >= 0) {
+                        log_info("Trying to halt qemu. Send SIGTERM again to trigger vmspawn to immediately terminate.");
+                        sd_event_source_set_userdata(s, NULL);
+                        return 0;
+                }
+        }
+
+        sd_event_exit(sd_event_source_get_event(s), 0);
+        return 0;
+}
+
+static int on_child_exit(sd_event_source *s, const siginfo_t *si, void *userdata) {
+        sd_event_exit(sd_event_source_get_event(s), 0);
+        return 0;
+}
+
+static int cmdline_add_vsock(char ***cmdline, int vsock_fd) {
+        int r;
+
+        r = strv_extend(cmdline, "-smbios");
+        if (r < 0)
+                return r;
+
+        union sockaddr_union addr;
+        socklen_t addr_len = sizeof addr.vm;
+        r = getsockname(vsock_fd, &addr.sa, &addr_len);
+        if (r < 0)
+                return -errno;
+        assert(addr_len >= sizeof addr.vm);
+        assert(addr.vm.svm_family == AF_VSOCK);
+
+        log_info("Using vsock-stream:%u:%u", (unsigned) VMADDR_CID_HOST, addr.vm.svm_port);
+        r = strv_extendf(cmdline, "type=11,value=io.systemd.credential:vmm.notify_socket=vsock-stream:%u:%u", (unsigned) VMADDR_CID_HOST, addr.vm.svm_port);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
 static int run_virtual_machine(void) {
         _cleanup_(ovmf_config_freep) OvmfConfig *ovmf_config = NULL;
         _cleanup_strv_free_ char **cmdline = NULL;
-        _cleanup_free_ char *machine = NULL, *qemu_binary = NULL, *mem = NULL, *kcl = NULL;
+        _cleanup_free_ char *machine = NULL, *qemu_binary = NULL, *mem = NULL;
         int r;
+        _cleanup_close_ int vsock_fd = -EBADF;
 
         bool use_kvm = arg_qemu_kvm > 0;
         if (arg_qemu_kvm < 0) {
@@ -232,11 +463,10 @@ static int run_virtual_machine(void) {
                             "falling back to OVMF firmware blobs without Secure Boot support.");
 
         const char *accel = use_kvm ? "kvm" : "tcg";
-#ifdef __aarch64__
+        if (IN_SET(native_architecture(), ARCHITECTURE_ARM64, ARCHITECTURE_ARM64_BE))
                 machine = strjoin("type=virt,accel=", accel);
-#else
+        else
                 machine = strjoin("type=q35,accel=", accel, ",smm=", on_off(ovmf_config->supports_sb));
-#endif
         if (!machine)
                 return log_oom();
 
@@ -256,9 +486,43 @@ static int run_virtual_machine(void) {
                 "-m", mem,
                 "-object", "rng-random,filename=/dev/urandom,id=rng0",
                 "-device", "virtio-rng-pci,rng=rng0,id=rng-device0",
-                "-nic", "user,model=virtio-net-pci",
-                "-cpu", "max"
+                "-nic", "user,model=virtio-net-pci"
         );
+        if (!cmdline)
+                return log_oom();
+
+        bool use_vsock = arg_qemu_vsock > 0 && ARCHITECTURE_SUPPORTS_SMBIOS;
+        if (arg_qemu_vsock < 0) {
+                r = qemu_check_vsock_support();
+                if (r < 0)
+                        return log_error_errno(r, "Failed to check for VSock support: %m");
+
+                use_vsock = r;
+        }
+
+        unsigned child_cid = VMADDR_CID_ANY;
+        _cleanup_close_ int child_vsock_fd = -EBADF;
+        if (use_vsock) {
+                if (arg_vsock_cid < UINT_MAX)
+                        child_cid = (unsigned)arg_vsock_cid;
+
+                r = vsock_fix_child_cid(&child_cid, arg_machine, &child_vsock_fd);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to fix CID for the guest vsock socket: %m");
+
+                r = strv_extend(&cmdline, "-device");
+                if (r < 0)
+                        return log_oom();
+
+                log_debug("vhost-vsock-pci,guest-cid=%u,vhostfd=%d", child_cid, child_vsock_fd);
+                r = strv_extendf(&cmdline, "vhost-vsock-pci,guest-cid=%u,vhostfd=%d", child_cid, child_vsock_fd);
+                if (r < 0)
+                        return log_oom();
+        }
+
+        r = strv_extend_strv(&cmdline, STRV_MAKE("-cpu", "max"), /* filter_duplicates= */ false);
+        if (r < 0)
+                return log_oom();
 
         if (arg_qemu_gui) {
                 r = strv_extend_strv(&cmdline, STRV_MAKE("-vga", "virtio"),  /* filter_duplicates= */ false);
@@ -271,12 +535,12 @@ static int run_virtual_machine(void) {
                         "-chardev", "stdio,mux=on,id=console,signal=off",
                         "-serial", "chardev:console",
                         "-mon", "console"
-                ), false);
+                ),  /* filter_duplicates= */ false);
                 if (r < 0)
                         return log_oom();
         }
 
-#if ARCHITECTURE_SUPPORTS_SMBIOS
+        if (ARCHITECTURE_SUPPORTS_SMBIOS) {
                 ssize_t n;
                 FOREACH_ARRAY(cred, arg_credentials, arg_n_credentials) {
                         _cleanup_free_ char *cred_data_b64 = NULL;
@@ -293,7 +557,7 @@ static int run_virtual_machine(void) {
                         if (r < 0)
                                 return log_oom();
                 }
-#endif
+        }
 
         r = strv_extend(&cmdline, "-drive");
         if (r < 0)
@@ -303,9 +567,9 @@ static int run_virtual_machine(void) {
         if (r < 0)
                 return log_oom();
 
+        _cleanup_(unlink_and_freep) char *ovmf_vars_to = NULL;
         if (ovmf_config->supports_sb) {
                 const char *ovmf_vars_from = ovmf_config->vars;
-                _cleanup_free_ char *ovmf_vars_to = NULL;
                 _cleanup_close_ int source_fd = -EBADF, target_fd = -EBADF;
 
                 r = tempfn_random_child(NULL, "vmspawn-", &ovmf_vars_to);
@@ -333,7 +597,7 @@ static int run_virtual_machine(void) {
                         "-global", "ICH9-LPC.disable_s3=1",
                         "-global", "driver=cfi.pflash01,property=secure,value=on",
                         "-drive"
-                ), false);
+                ),  /* filter_duplicates= */ false);
                 if (r < 0)
                         return log_oom();
 
@@ -353,13 +617,13 @@ static int run_virtual_machine(void) {
         r = strv_extend_strv(&cmdline, STRV_MAKE(
                 "-device", "virtio-scsi-pci,id=scsi",
                 "-device", "scsi-hd,drive=mkosi,bootindex=1"
-        ), false);
+        ),  /* filter_duplicates= */ false);
         if (r < 0)
                 return log_oom();
 
-        if (strv_length(arg_parameters) != 0) {
-#if ARCHITECTURE_SUPPORTS_SMBIOS
-                kcl = strv_join(arg_parameters, " ");
+        if (!strv_isempty(arg_parameters)) {
+                if (ARCHITECTURE_SUPPORTS_SMBIOS) {
+                        _cleanup_free_ char *kcl = strv_join(arg_parameters, " ");
                         if (!kcl)
                                 return log_oom();
 
@@ -370,13 +634,39 @@ static int run_virtual_machine(void) {
                         r = strv_extendf(&cmdline, "type=11,value=io.systemd.stub.kernel-cmdline-extra=%s", kcl);
                         if (r < 0)
                                 return log_oom();
-#else
+                } else
                         log_warning("Cannot append extra args to kernel cmdline, native architecture doesn't support SMBIOS");
-#endif
         }
 
+        if (use_vsock) {
+                vsock_fd = open_vsock();
+                if (vsock_fd < 0)
+                        return log_error_errno(vsock_fd, "Failed to open vsock: %m");
+
+                r = cmdline_add_vsock(&cmdline, vsock_fd);
+                if (r == -ENOMEM)
+                        return log_oom();
+                if (r < 0)
+                        return log_error_errno(r, "Failed to call getsockname on vsock: %m");
+        }
+
+        _cleanup_(sd_event_source_unrefp) sd_event_source *notify_event_source = NULL;
+        _cleanup_(sd_event_unrefp) sd_event *event = NULL;
+        r = sd_event_new(&event);
+        if (r < 0)
+                return log_error_errno(r, "Failed to get default event source: %m");
+
+        (void) sd_event_set_watchdog(event, true);
+
         pid_t child_pid;
-        r = safe_fork(qemu_binary, 0, &child_pid);
+        r = safe_fork_full(
+                        qemu_binary,
+                        NULL,
+                        &child_vsock_fd, 1, /* pass the vsock fd to qemu */
+                        FORK_CLOEXEC_OFF,
+                        &child_pid);
+        if (r < 0)
+                return log_error_errno(r, "Failed to fork off %s: %m", qemu_binary);
         if (r == 0) {
                 /* set TERM and LANG if they are missing */
                 if (setenv("TERM", "vt220", 0) < 0)
@@ -390,7 +680,64 @@ static int run_virtual_machine(void) {
                 _exit(EXIT_FAILURE);
         }
 
-        return wait_for_terminate_and_check(qemu_binary, child_pid, WAIT_LOG);
+
+        int exit_status = INT_MAX;
+        if (use_vsock) {
+                r = setup_notify_parent(event, vsock_fd, &exit_status, &notify_event_source);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to setup event loop to handle vsock notify events: %m");
+        }
+
+        /* shutdown qemu when we are shutdown */
+        (void) sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, PID_TO_PTR(child_pid));
+        (void) sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, PID_TO_PTR(child_pid));
+
+        (void) sd_event_add_signal(event, NULL, SIGRTMIN+18, sigrtmin18_handler, NULL);
+
+        /* Exit when the child exits */
+        (void) sd_event_add_child(event, NULL, child_pid, WEXITED, on_child_exit, NULL);
+
+        r = sd_event_loop(event);
+        if (r < 0)
+                return log_error_errno(r, "Failed to run event loop: %m");
+
+        if (use_vsock) {
+                if (exit_status == INT_MAX) {
+                        log_debug("Couldn't retrieve inner EXIT_STATUS from vsock");
+                        return EXIT_SUCCESS;
+                }
+                if (exit_status != 0)
+                        log_warning("Non-zero exit code received: %d", exit_status);
+                return exit_status;
+        }
+
+        return 0;
+}
+
+static int determine_names(void) {
+        int r;
+
+        if (!arg_image)
+                return log_error_errno(SYNTHETIC_ERRNO(-EINVAL), "Missing required argument -i/--image=, quitting");
+
+        if (!arg_machine) {
+                char *e;
+
+                r = path_extract_filename(arg_image, &arg_machine);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to extract file name from '%s': %m", arg_image);
+
+                /* Truncate suffix if there is one */
+                e = endswith(arg_machine, ".raw");
+                if (e)
+                        *e = 0;
+
+                hostname_cleanup(arg_machine);
+                if (!hostname_is_valid(arg_machine, 0))
+                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Failed to determine machine name automatically, please use -M.");
+        }
+
+        return 0;
 }
 
 static int run(int argc, char *argv[]) {
@@ -402,12 +749,15 @@ static int run(int argc, char *argv[]) {
         if (r <= 0)
                 goto finish;
 
-        if (!arg_image) {
-                log_error("Missing required argument -i/--image, quitting");
+        r = determine_names();
+        if (r < 0)
                 goto finish;
-        }
+
+        assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGCHLD, SIGTERM, SIGINT, SIGRTMIN+18, -1) >= 0);
 
         r = run_virtual_machine();
+        if (r > 0)
+                ret = r;
 finish:
         machine_credential_free_all(arg_credentials, arg_n_credentials);