diff --git a/src/core/umount.c b/src/core/umount.c
index 8ac40e5759..b46d133920 100644
--- a/src/core/umount.c
+++ b/src/core/umount.c
@@ -37,7 +37,6 @@
 #include "fd-util.h"
 #include "fstab-util.h"
 #include "linux-3.13/dm-ioctl.h"
-#include "list.h"
 #include "mount-setup.h"
 #include "mount-util.h"
 #include "path-util.h"
@@ -52,15 +51,6 @@
 DEFINE_TRIVIAL_CLEANUP_FUNC(struct libmnt_table*, mnt_free_table);
 DEFINE_TRIVIAL_CLEANUP_FUNC(struct libmnt_iter*, mnt_free_iter);
 
-typedef struct MountPoint {
-        char *path;
-        char *remount_options;
-        unsigned long remount_flags;
-        bool try_remount_ro;
-        dev_t devnum;
-        LIST_FIELDS(struct MountPoint, mount_point);
-} MountPoint;
-
 static void mount_point_free(MountPoint **head, MountPoint *m) {
         assert(head);
         assert(m);
@@ -72,14 +62,14 @@ static void mount_point_free(MountPoint **head, MountPoint *m) {
         free(m);
 }
 
-static void mount_points_list_free(MountPoint **head) {
+void mount_points_list_free(MountPoint **head) {
         assert(head);
 
         while (*head)
                 mount_point_free(head, *head);
 }
 
-static int mount_points_list_get(MountPoint **head) {
+int mount_points_list_get(const char *mountinfo, MountPoint **head) {
         _cleanup_(mnt_free_tablep) struct libmnt_table *t = NULL;
         _cleanup_(mnt_free_iterp) struct libmnt_iter *i = NULL;
         int r;
@@ -91,9 +81,9 @@ static int mount_points_list_get(MountPoint **head) {
         if (!t || !i)
                 return log_oom();
 
-        r = mnt_table_parse_mtab(t, NULL);
+        r = mnt_table_parse_mtab(t, mountinfo);
         if (r < 0)
-                return log_error_errno(r, "Failed to parse /proc/self/mountinfo: %m");
+                return log_error_errno(r, "Failed to parse %s: %m", mountinfo);
 
         for (;;) {
                 struct libmnt_fs *fs;
@@ -108,7 +98,7 @@ static int mount_points_list_get(MountPoint **head) {
                 if (r == 1)
                         break;
                 if (r < 0)
-                        return log_error_errno(r, "Failed to get next entry from /proc/self/mountinfo: %m");
+                        return log_error_errno(r, "Failed to get next entry from %s: %m", mountinfo);
 
                 path = mnt_fs_get_target(fs);
                 if (!path)
@@ -661,7 +651,7 @@ static int umount_all_once(bool *changed, int umount_log_level) {
         assert(changed);
 
         LIST_HEAD_INIT(mp_list_head);
-        r = mount_points_list_get(&mp_list_head);
+        r = mount_points_list_get(NULL, &mp_list_head);
         if (r < 0)
                 goto end;
 
diff --git a/src/core/umount.h b/src/core/umount.h
index a6613e6ad6..fa1c6de90d 100644
--- a/src/core/umount.h
+++ b/src/core/umount.h
@@ -20,6 +20,8 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+#include "list.h"
+
 int umount_all(bool *changed, int umount_log_level);
 
 int swapoff_all(bool *changed);
@@ -27,3 +29,16 @@ int swapoff_all(bool *changed);
 int loopback_detach_all(bool *changed, int umount_log_level);
 
 int dm_detach_all(bool *changed, int umount_log_level);
+
+/* This is exported just for testing */
+typedef struct MountPoint {
+        char *path;
+        char *remount_options;
+        unsigned long remount_flags;
+        bool try_remount_ro;
+        dev_t devnum;
+        LIST_FIELDS(struct MountPoint, mount_point);
+} MountPoint;
+
+int mount_points_list_get(const char *mountinfo, MountPoint **head);
+void mount_points_list_free(MountPoint **head);
diff --git a/src/test/meson.build b/src/test/meson.build
index 4f28ef8722..e45618ef88 100644
--- a/src/test/meson.build
+++ b/src/test/meson.build
@@ -652,6 +652,14 @@ tests += [
          [],
          [libdl],
          '', 'manual'],
+
+        [['src/test/test-umount.c',
+          'src/core/mount-setup.c',
+          'src/core/mount-setup.h',
+          'src/core/umount.c',
+          'src/core/umount.h'],
+         [],
+         [libmount]],
 ]
 
 ############################################################
diff --git a/src/test/test-umount.c b/src/test/test-umount.c
new file mode 100644
index 0000000000..ca626041f6
--- /dev/null
+++ b/src/test/test-umount.c
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include "log.h"
+#include "string-util.h"
+#include "tests.h"
+#include "umount.h"
+#include "util.h"
+
+static void test_mount_points_list(const char *fname) {
+        LIST_HEAD(MountPoint, mp_list_head);
+        MountPoint *m;
+
+        log_info("/* %s(\"%s\") */", __func__, fname ?: "/proc/self/mountinfo");
+
+        LIST_HEAD_INIT(mp_list_head);
+        assert_se(mount_points_list_get(fname, &mp_list_head) >= 0);
+
+        LIST_FOREACH(mount_point, m, mp_list_head)
+                log_debug("path=%s o=%s f=0x%lx try-ro=%s dev=%u:%u",
+                          m->path,
+                          strempty(m->remount_options),
+                          m->remount_flags,
+                          yes_no(m->try_remount_ro),
+                          major(m->devnum), minor(m->devnum));
+
+        mount_points_list_free(&mp_list_head);
+}
+
+int main(int argc, char **argv) {
+        log_set_max_level(LOG_DEBUG);
+        log_parse_environment();
+        log_open();
+
+        test_mount_points_list(NULL);
+        test_mount_points_list(get_testdata_dir("/test-umount/empty.mountinfo"));
+        test_mount_points_list(get_testdata_dir("/test-umount/garbled.mountinfo"));
+        test_mount_points_list(get_testdata_dir("/test-umount/rhbug-1554943.mountinfo"));
+}
diff --git a/test/meson.build b/test/meson.build
index f86cf388e0..51c47793e0 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -174,6 +174,9 @@ test_data_files = '''
         testsuite.target
         timers.target
         unstoppable.service
+        test-umount/empty.mountinfo
+        test-umount/garbled.mountinfo
+        test-umount/rhbug-1554943.mountinfo
 '''.split()
 
 if conf.get('ENABLE_RESOLVE') == 1
diff --git a/test/test-umount/empty.mountinfo b/test/test-umount/empty.mountinfo
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/test/test-umount/garbled.mountinfo b/test/test-umount/garbled.mountinfo
new file mode 100644
index 0000000000..5f28aea409
--- /dev/null
+++ b/test/test-umount/garbled.mountinfo
@@ -0,0 +1,5 @@
+18 63 1000999:110999 / /sys rw,nosuid,nodev,noexec,relatime shared:2 - sysfs sysfs rw
+44 44
+asdfasdf asdfasdf asdf asdfasdfasdf
+asdfsadfasd
+95 63 8:1 / /one-good-entry rw,relatime shared:34 - ext4 /dev/sda1 rw,data=ordered
diff --git a/test/test-umount/rhbug-1554943.mountinfo b/test/test-umount/rhbug-1554943.mountinfo
new file mode 100644
index 0000000000..d8bdf35862
--- /dev/null
+++ b/test/test-umount/rhbug-1554943.mountinfo
@@ -0,0 +1,47 @@
+18 63 0:18 / /sys rw,nosuid,nodev,noexec,relatime shared:2 - sysfs sysfs rw
+19 63 0:4 / /proc rw,nosuid,nodev,noexec,relatime shared:23 - proc proc rw
+20 63 0:6 / /dev rw,nosuid shared:19 - devtmpfs devtmpfs rw,size=3549752k,nr_inodes=887438,mode=755
+21 18 0:7 / /sys/kernel/security rw,nosuid,nodev,noexec,relatime shared:3 - securityfs securityfs rw
+22 20 0:19 / /dev/shm rw,nosuid,nodev shared:20 - tmpfs tmpfs rw
+23 20 0:20 / /dev/pts rw,nosuid,noexec,relatime shared:21 - devpts devpts rw,gid=5,mode=620,ptmxmode=000
+24 63 0:21 / /run rw,nosuid,nodev shared:22 - tmpfs tmpfs rw,mode=755
+25 18 0:22 / /sys/fs/cgroup ro,nosuid,nodev,noexec shared:4 - tmpfs tmpfs ro,mode=755
+26 25 0:23 / /sys/fs/cgroup/unified rw,nosuid,nodev,noexec,relatime shared:5 - cgroup2 cgroup rw
+27 25 0:24 / /sys/fs/cgroup/systemd rw,nosuid,nodev,noexec,relatime shared:6 - cgroup cgroup rw,xattr,name=systemd
+28 18 0:25 / /sys/fs/pstore rw,nosuid,nodev,noexec,relatime shared:17 - pstore pstore rw
+29 25 0:26 / /sys/fs/cgroup/cpu,cpuacct rw,nosuid,nodev,noexec,relatime shared:7 - cgroup cgroup rw,cpu,cpuacct
+30 25 0:27 / /sys/fs/cgroup/perf_event rw,nosuid,nodev,noexec,relatime shared:8 - cgroup cgroup rw,perf_event
+31 25 0:28 / /sys/fs/cgroup/freezer rw,nosuid,nodev,noexec,relatime shared:9 - cgroup cgroup rw,freezer
+32 25 0:29 / /sys/fs/cgroup/hugetlb rw,nosuid,nodev,noexec,relatime shared:10 - cgroup cgroup rw,hugetlb
+33 25 0:30 / /sys/fs/cgroup/cpuset rw,nosuid,nodev,noexec,relatime shared:11 - cgroup cgroup rw,cpuset
+34 25 0:31 / /sys/fs/cgroup/net_cls,net_prio rw,nosuid,nodev,noexec,relatime shared:12 - cgroup cgroup rw,net_cls,net_prio
+35 25 0:32 / /sys/fs/cgroup/memory rw,nosuid,nodev,noexec,relatime shared:13 - cgroup cgroup rw,memory
+36 25 0:33 / /sys/fs/cgroup/pids rw,nosuid,nodev,noexec,relatime shared:14 - cgroup cgroup rw,pids
+37 25 0:34 / /sys/fs/cgroup/blkio rw,nosuid,nodev,noexec,relatime shared:15 - cgroup cgroup rw,blkio
+38 25 0:35 / /sys/fs/cgroup/devices rw,nosuid,nodev,noexec,relatime shared:16 - cgroup cgroup rw,devices
+61 18 0:36 / /sys/kernel/config rw,relatime shared:18 - configfs configfs rw
+63 0 8:17 / / rw,relatime shared:1 - ext4 /dev/sdb1 rw,lazytime,commit=30,inode_readahead_blks=16
+39 18 0:8 / /sys/kernel/debug rw,relatime shared:24 - debugfs debugfs rw
+40 20 0:37 / /dev/hugepages rw,relatime shared:25 - hugetlbfs hugetlbfs rw,pagesize=2M
+41 19 0:38 / /proc/sys/fs/binfmt_misc rw,relatime shared:26 - autofs systemd-1 rw,fd=32,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=14807
+42 20 0:17 / /dev/mqueue rw,relatime shared:27 - mqueue mqueue rw
+43 63 0:39 / /var/www/sessiondata rw,nosuid,noexec,noatime shared:28 - tmpfs tmpfs rw,size=4194304k
+75 63 0:40 / /usr/share/mysql-test/var rw,noatime shared:29 - tmpfs tmpfs rw,size=4194304k,mode=750,uid=27,gid=27
+77 63 8:33 / /Volumes/dune rw,relatime shared:30 - ext4 /dev/sdc1 rw,lazytime,commit=30,inode_readahead_blks=16
+79 63 8:33 /builduser /home/builduser rw,relatime shared:30 - ext4 /dev/sdc1 rw,lazytime,commit=30,inode_readahead_blks=16
+81 77 0:41 / /Volumes/dune/mysql_data/autotest rw,nosuid,noexec,noatime shared:31 - tmpfs tmpfs rw,size=4194304k,mode=700,uid=27,gid=27
+83 63 8:33 /.tmp /var/tmp rw,relatime shared:30 - ext4 /dev/sdc1 rw,lazytime,commit=30,inode_readahead_blks=16
+85 77 0:42 / /Volumes/dune/www-servers/cms/cms/temp rw,nosuid,noexec,noatime shared:32 - tmpfs tmpfs rw,size=4194304k,mode=770,uid=48,gid=48
+87 77 8:33 /buildserver/autotest /Volumes/dune/www-servers/autotest rw,relatime shared:30 - ext4 /dev/sdc1 rw,lazytime,commit=30,inode_readahead_blks=16
+89 63 8:33 /.tmp /tmp rw,relatime shared:30 - ext4 /dev/sdc1 rw,lazytime,commit=30,inode_readahead_blks=16
+91 77 0:43 / /Volumes/dune/www-servers/cms/cms/logs rw,nosuid,noexec,noatime shared:33 - tmpfs tmpfs rw,size=4194304k,mode=770,uid=48,gid=48
+93 63 8:33 /www-servers/cms /usr/local/sftp-homes/flow/cms rw,relatime shared:30 - ext4 /dev/sdc1 rw,lazytime,commit=30,inode_readahead_blks=16
+95 63 8:1 / /boot rw,relatime shared:34 - ext4 /dev/sda1 rw,data=ordered
+97 79 0:44 / /home/builduser/rpmbuild/PHP-PGO/logs rw,nosuid,noatime shared:35 - tmpfs tmpfs rw,size=4194304k,mode=770,uid=5000,gid=5000
+98 77 0:44 / /Volumes/dune/builduser/rpmbuild/PHP-PGO/logs rw,nosuid,noatime shared:35 - tmpfs tmpfs rw,size=4194304k,mode=770,uid=5000,gid=5000
+101 63 9:0 / /mnt/raid10 rw,relatime shared:36 - ext4 /dev/md0 rw,lazytime,commit=30,stripe=128,inode_readahead_blks=16
+558 24 0:52 / /run/user/48 rw,nosuid,nodev,relatime shared:83 - tmpfs tmpfs rw,size=711220k,mode=700,uid=48,gid=48
+588 24 0:53 / /run/user/5000 rw,nosuid,nodev,relatime shared:135 - tmpfs tmpfs rw,size=711220k,mode=700,uid=5000,gid=5000
+613 24 0:54 / /run/user/4503 rw,nosuid,nodev,relatime shared:85 - tmpfs tmpfs rw,size=711220k,mode=700,uid=4503,gid=4503
+653 24 0:45 / /run/user/4500 rw,nosuid,nodev,relatime shared:87 - tmpfs tmpfs rw,size=711220k,mode=700,uid=4500,gid=48
+699 24 0:55 / /run/user/0 rw,nosuid,nodev,relatime shared:89 - tmpfs tmpfs rw,size=711220k,mode=700