diff --git a/src/basic/escape.c b/src/basic/escape.c
index e1771bf432..9af8efacc7 100644
--- a/src/basic/escape.c
+++ b/src/basic/escape.c
@@ -447,10 +447,10 @@ char* escape_non_printable_full(const char *str, size_t console_width, XEscapeFl
                                                       FLAGS_SET(flags, XESCAPE_FORCE_ELLIPSIS));
 }
 
-char* octescape(const char *s, size_t len) {
+char* octescape_full(const char *s, size_t len, const char *bad) {
         char *buf, *t;
 
-        /* Escapes \ and " chars, in \nnn style escaping. */
+        /* Escapes all chars in bad, in addition to \ and " chars, in \nnn octal style escaping. */
 
         assert(s || len == 0);
 
@@ -467,7 +467,7 @@ char* octescape(const char *s, size_t len) {
         for (size_t i = 0; i < len; i++) {
                 uint8_t u = (uint8_t) s[i];
 
-                if (u < ' ' || u >= 127 || IN_SET(u, '\\', '"')) {
+                if (u < ' ' || u >= 127 || IN_SET(u, '\\', '"') || (bad && strchr(bad, u))) {
                         *(t++) = '\\';
                         *(t++) = '0' + (u >> 6);
                         *(t++) = '0' + ((u >> 3) & 7);
diff --git a/src/basic/escape.h b/src/basic/escape.h
index a8b68fa75c..625758f2f4 100644
--- a/src/basic/escape.h
+++ b/src/basic/escape.h
@@ -59,7 +59,10 @@ char* xescape_full(const char *s, const char *bad, size_t console_width, XEscape
 static inline char* xescape(const char *s, const char *bad) {
         return xescape_full(s, bad, SIZE_MAX, 0);
 }
-char* octescape(const char *s, size_t len);
+char* octescape_full(const char *s, size_t len, const char *bad);
+static inline char* octescape(const char *s, size_t len) {
+        return octescape_full(s, len, NULL);
+}
 char* decescape(const char *s, size_t len, const char *bad) _nonnull_if_nonzero_(1, 2);
 char* escape_non_printable_full(const char *str, size_t console_width, XEscapeFlags flags);
 
diff --git a/src/vmspawn/vmspawn.c b/src/vmspawn/vmspawn.c
index ff76c5e4d3..e14d2bb5f3 100644
--- a/src/vmspawn/vmspawn.c
+++ b/src/vmspawn/vmspawn.c
@@ -3033,6 +3033,8 @@ static int run_virtual_machine(int kvm_device_fd, int vhost_device_fd) {
                         return log_oom();
         }
 
+        _cleanup_free_ char *fstab_extra = NULL;
+
         for (size_t j = 0; j < arg_runtime_mounts.n_mounts; j++) {
                 RuntimeMount *m = arg_runtime_mounts.mounts + j;
                 _cleanup_free_ char *listen_address = NULL;
@@ -3079,15 +3081,39 @@ static int run_virtual_machine(int kvm_device_fd, int vhost_device_fd) {
                 if (r < 0)
                         return r;
 
-                _cleanup_free_ char *clean_target = xescape(m->target, "\":");
-                if (!clean_target)
+                /* fstab uses whitespace as field separator, so octal-escape spaces in paths */
+                _cleanup_free_ char *escaped_target = octescape_full(m->target, SIZE_MAX, " \t");
+                if (!escaped_target)
                         return log_oom();
 
-                if (strv_extendf(&arg_kernel_cmdline_extra, "systemd.mount-extra=\"%s:%s:virtiofs:%s\"",
-                                 id, clean_target, m->read_only ? "ro" : "rw") < 0)
+                if (strextendf(&fstab_extra, "%s %s virtiofs %s,x-initrd.mount\n",
+                               id, escaped_target, m->read_only ? "ro" : "rw") < 0)
                         return log_oom();
         }
 
+        if (fstab_extra) {
+                /* If the user already specified a fstab.extra credential, combine it with ours */
+                MachineCredential *existing = machine_credential_find(&arg_credentials, "fstab.extra");
+                if (existing) {
+                        _cleanup_free_ char *combined = NULL;
+
+                        if (existing->size > 0 && existing->data[existing->size - 1] != '\n')
+                                r = asprintf(&combined, "%.*s\n%s", (int) existing->size, existing->data, fstab_extra);
+                        else
+                                r = asprintf(&combined, "%.*s%s", (int) existing->size, existing->data, fstab_extra);
+                        if (r < 0)
+                                return log_oom();
+
+                        erase_and_free(existing->data);
+                        existing->data = TAKE_PTR(combined);
+                        existing->size = r;
+                } else {
+                        r = machine_credential_add(&arg_credentials, "fstab.extra", fstab_extra, SIZE_MAX);
+                        if (r < 0)
+                                return r;
+                }
+        }
+
         _cleanup_(rm_rf_physical_and_freep) char *smbios_dir = NULL;
         r = mkdtemp_malloc("/var/tmp/vmspawn-smbios-XXXXXX", &smbios_dir);
         if (r < 0)