shutdown: get only active md arrays.

Current md_list_get() implementation filters all block devices, started from
"md*". This is ambiguous because list could contain:
- partitions created upon md device (mdXpY)
- external metadata container- specific type of md array.

For partitions there is no issue, because they aren't handle STOP_ARRAY
ioctl sent later. It generates misleading errors only.

Second case is more problematic because containers are not locked in kernel.
They are stopped even if container member array is active. For that reason
reboot or shutdown flow could be blocked because metadata manager cannot be
restarted after switch root on shutdown.

Add filters to remove partitions and containers from md_list. Partitions
can be excluded by DEVTYPE. Containers are determined by MD_LEVEL
property, we are excluding all with "container" value.

Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@linux.intel.com>

README

@@ -353,6 +353,13 @@ WARNINGS and TAINT FLAGS:
         For more information on this issue consult
         https://www.freedesktop.org/wiki/Software/systemd/separate-usr-is-broken
 
+        systemd will warn if the filesystem is not usr-merged (i.e.: /bin, /sbin
+        and /lib* are not symlinks to their counterparts under /usr). Taint flag
+        'unmerged-usr' will be set when this condition is detected.
+
+        For more information on this issue consult
+        https://www.freedesktop.org/wiki/Software/systemd/TheCaseForTheUsrMerge
+
         systemd requires that the /run mount point exists. systemd also
         requires that /var/run is a symlink to /run. Taint flag 'var-run-bad'
         will be set when this condition is detected.

README.md

@@ -13,6 +13,7 @@ System and Service Manager
 [![CentOS CI - CentOS 8](https://jenkins-systemd.apps.ocp.ci.centos.org/buildStatus/icon?subject=CentOS%20CI%20-%20CentOS%208&job=upstream-centos8)](https://jenkins-systemd.apps.ocp.ci.centos.org/job/upstream-centos8/)<br/>
 [![CentOS CI - Arch](https://jenkins-systemd.apps.ocp.ci.centos.org/buildStatus/icon?subject=CentOS%20CI%20-%20Arch&job=upstream-vagrant-archlinux)](https://jenkins-systemd.apps.ocp.ci.centos.org/job/upstream-vagrant-archlinux/)<br/>
 [![CentOS CI - Arch (sanitizers)](https://jenkins-systemd.apps.ocp.ci.centos.org/buildStatus/icon?subject=CentOS%20CI%20-%20Arch%20(sanitizers)&job=upstream-vagrant-archlinux-sanitizers)](https://jenkins-systemd.apps.ocp.ci.centos.org/job/upstream-vagrant-archlinux-sanitizers/)<br/>
+[![CentOS CI - Rawhide (SELinux)](https://jenkins-systemd.apps.ocp.ci.centos.org/buildStatus/icon?subject=CentOS%20CI%20-%20Rawhide%20(SELinux)&job=upstream-vagrant-rawhide-selinux)](https://jenkins-systemd.apps.ocp.ci.centos.org/view/Upstream/job/upstream-vagrant-rawhide-selinux/)<br/>
 [![Fossies codespell report](https://fossies.org/linux/test/systemd-main.tar.gz/codespell.svg)](https://fossies.org/linux/test/systemd-main.tar.gz/codespell.html)</br>
 [![Coverage Status](https://coveralls.io/repos/github/systemd/systemd/badge.svg?branch=main)](https://coveralls.io/github/systemd/systemd?branch=main)</br>
 [![Packaging status](https://repology.org/badge/tiny-repos/systemd.svg)](https://repology.org/project/systemd/versions)

TODO

@@ -78,6 +78,13 @@ Janitorial Clean-ups:
 
 Features:
 
+* get_color_mode() should probably check the $COLORTERM environment variable
+  which most terminal environments appear to set.
+
+* firstboot: maybe just default to C.UTF-8 locale if nothing is set, so that we
+  don't query this unnecessarily in entirely uninitialized
+  containers. (i.e. containers with empty /etc).
+
 * systemd creds hookup with qemu fw_cfg. (Quite possibly might not need any
   code at all, given the fw_cfg stuff are just files, but we should then
   document how to use it). Goal: provide symmetric ways to pass creds to nspawn

hwdb.d/60-evdev.hwdb

@@ -3,11 +3,6 @@
 # The lookup keys are composed in:
 #   60-evdev.rules
 #
-# Note: The format of the "evdev:" prefix match key is a contract between the
-# rules file and the hardware data, it might change in later revisions to
-# support more or better matches, it is not necessarily expected to be a stable
-# ABI.
-#
 # Match string formats:
 # evdev:<modalias>
 # evdev:name:<device name>:dmi:<dmi string>

hwdb.d/60-input-id.hwdb

@@ -3,11 +3,6 @@
 # The lookup keys are composed in:
 #   60-input-id.rules
 #
-# Note: The format of the "input-id:" prefix match key is a contract between
-# the rules file and the hardware data, it might change in later revisions to
-# support more or better matches, it is not necessarily expected to be a stable
-# ABI.
-#
 # Match string formats:
 # id-input:modalias:<modalias>
 #

hwdb.d/60-keyboard.hwdb

@@ -13,11 +13,6 @@
 # The lookup keys are composed in:
 #   60-evdev.rules
 #
-# Note: The format of the "evdev:" prefix match key is a contract between the
-# rules file and the hardware data, it might change in later revisions to
-# support more or better matches, it is not necessarily expected to be a stable
-# ABI.
-#
 # Supported hardware matches are:
 #  - Generic input devices match:
 #      evdev:input:bZZZZvYYYYpXXXXeWWWW-VVVV

hwdb.d/60-sensor.hwdb

@@ -3,11 +3,6 @@
 # The lookup keys are composed in:
 #   60-sensor.rules
 #
-# Note: The format of the "sensor:" prefix match key is a contract between the
-# rules file and the hardware data, it might change in later revisions to
-# support more or better matches, it is not necessarily expected to be a stable
-# ABI.
-#
 # Match string formats:
 # sensor:modalias:<parent modalias pattern>:dmi:<dmi pattern>
 #

hwdb.d/70-mouse.hwdb

@@ -6,11 +6,6 @@
 # The lookup keys are composed in:
 #   70-mouse.rules
 #
-# Note: The format of the "mouse:" prefix match key is a contract between the
-# rules file and the hardware data, it might change in later revisions to
-# support more or better matches, it is not necessarily expected to be a stable
-# ABI.
-#
 # Match key format:
 # mouse:<subsystem>:v<vid>p<pid>:name:<name>:
 #

hwdb.d/70-pointingstick.hwdb

@@ -7,10 +7,6 @@
 # The lookup keys are composed in:
 #   60-evdev.rules
 #
-# Note: The format of the "evdev:" prefix match key is a contract between the
-# rules file and the hardware data, it might change in later revisions to
-# support more or better matches, it is not necessarily a stable ABI.
-#
 # Supported hardware matches are:
 #  - Generic input devices match:
 #      evdev:input:bZZZZvYYYYpXXXXeWWWW-VVVV

man/systemd-analyze.xml

@@ -819,10 +819,12 @@ $ systemd-analyze verify /tmp/source:alias.service
         <listitem><para>Control verification of units and their dependencies and whether
         <command>systemd-analyze verify</command> exits with a non-zero process exit status or not. With
         <command>yes</command>, return a non-zero process exit status when warnings arise during verification
-        of either the specified unit or any of its associated dependencies. This is the default. With
-        <command>no</command>, return a non-zero process exit status when warnings arise during verification
-        of only the specified unit. With <command>one</command>, return a non-zero process exit status when
-        warnings arise during verification of either the specified unit or its immediate dependencies. </para></listitem>
+        of either the specified unit or any of its associated dependencies. With <command>no</command>,
+        return a non-zero process exit status when warnings arise during verification of only the specified
+        unit. With <command>one</command>, return a non-zero process exit status when warnings arise during
+        verification of either the specified unit or its immediate dependencies. If this option is not
+        specified, zero is returned as the exit status regardless whether warnings arise during verification
+        or not.</para></listitem>
       </varlistentry>
 
       <varlistentry>

src/analyze/analyze.c

@@ -90,7 +90,7 @@ PagerFlags arg_pager_flags = 0;
 BusTransport arg_transport = BUS_TRANSPORT_LOCAL;
 const char *arg_host = NULL;
 LookupScope arg_scope = LOOKUP_SCOPE_SYSTEM;
-RecursiveErrors arg_recursive_errors = RECURSIVE_ERRORS_YES;
+RecursiveErrors arg_recursive_errors = _RECURSIVE_ERRORS_INVALID;
 bool arg_man = true;
 bool arg_generators = false;
 char *arg_root = NULL;

src/basic/strv.c

@@ -351,7 +351,7 @@ int strv_split_colon_pairs(char ***t, const char *s) {
         return (int) n;
 }
 
-char* strv_join_full(char * const *l, const char *separator, const char *prefix, bool unescape_separators) {
+char* strv_join_full(char * const *l, const char *separator, const char *prefix, bool escape_separator) {
         char *r, *e;
         size_t n, k, m;
 
@@ -361,7 +361,7 @@ char* strv_join_full(char * const *l, const char *separator, const char *prefix,
         k = strlen(separator);
         m = strlen_ptr(prefix);
 
-        if (unescape_separators) /* If there separator is multi-char, we won't know how to escape it. */
+        if (escape_separator) /* If the separator was multi-char, we wouldn't know how to escape it. */
                 assert(k == 1);
 
         n = 0;
@@ -369,7 +369,7 @@ char* strv_join_full(char * const *l, const char *separator, const char *prefix,
                 if (s != l)
                         n += k;
 
-                bool needs_escaping = unescape_separators && strchr(*s, separator[0]);
+                bool needs_escaping = escape_separator && strchr(*s, *separator);
 
                 n += m + strlen(*s) * (1 + needs_escaping);
         }
@@ -386,11 +386,11 @@ char* strv_join_full(char * const *l, const char *separator, const char *prefix,
                 if (prefix)
                         e = stpcpy(e, prefix);
 
-                bool needs_escaping = unescape_separators && strchr(*s, separator[0]);
+                bool needs_escaping = escape_separator && strchr(*s, *separator);
 
                 if (needs_escaping)
                         for (size_t i = 0; (*s)[i]; i++) {
-                                if ((*s)[i] == separator[0])
+                                if ((*s)[i] == *separator)
                                         *(e++) = '\\';
                                 *(e++) = (*s)[i];
                         }

src/basic/strv.h

@@ -101,7 +101,7 @@ static inline char** strv_split_newlines(const char *s) {
  * string in the vector is an empty string. */
 int strv_split_colon_pairs(char ***t, const char *s);
 
-char* strv_join_full(char * const *l, const char *separator, const char *prefix, bool escape_separtor);
+char* strv_join_full(char * const *l, const char *separator, const char *prefix, bool escape_separator);
 static inline char *strv_join(char * const *l, const char *separator) {
         return strv_join_full(l, separator, NULL, false);
 }

src/core/manager.c

@@ -4370,71 +4370,58 @@ static int short_uid_range(const char *path) {
         return !uid_range_covers(p, n, 0, 65535);
 }
 
-char *manager_taint_string(Manager *m) {
-        _cleanup_free_ char *destination = NULL, *overflowuid = NULL, *overflowgid = NULL;
-        struct utsname uts;
-        char *buf, *e;
-        int r;
-
-        /* Returns a "taint string", e.g. "local-hwclock:var-run-bad".  Only things that are detected at
-         * runtime should be tagged here. For stuff that is set during compilation, emit a warning in the
+char* manager_taint_string(const Manager *m) {
+        /* Returns a "taint string", e.g. "local-hwclock:var-run-bad". Only things that are detected at
+         * runtime should be tagged here. For stuff that is known during compilation, emit a warning in the
          * configuration phase. */
 
         assert(m);
 
-        buf = new(char, sizeof("split-usr:"
-                               "cgroups-missing:"
-                               "cgroupsv1:"
-                               "local-hwclock:"
-                               "var-run-bad:"
-                               "overflowuid-not-65534:"
-                               "overflowgid-not-65534:"
-                               "old-kernel:"
-                               "short-uid-range:"
-                               "short-gid-range:"));
-        if (!buf)
-                return NULL;
-
-        e = buf;
-        buf[0] = 0;
+        const char* stage[12] = {};
+        size_t n = 0;
 
         if (m->taint_usr)
-                e = stpcpy(e, "split-usr:");
+                stage[n++] = "split-usr";
+
+        _cleanup_free_ char *usrbin = NULL;
+        if (readlink_malloc("/bin", &usrbin) < 0 || !PATH_IN_SET(usrbin, "usr/bin", "/usr/bin"))
+                stage[n++] = "unmerged-usr";
 
         if (access("/proc/cgroups", F_OK) < 0)
-                e = stpcpy(e, "cgroups-missing:");
+                stage[n++] = "cgroups-missing";
 
         if (cg_all_unified() == 0)
-                e = stpcpy(e, "cgroupsv1:");
+                stage[n++] = "cgroupsv1";
 
         if (clock_is_localtime(NULL) > 0)
-                e = stpcpy(e, "local-hwclock:");
+                stage[n++] = "local-hwclock";
 
-        r = readlink_malloc("/var/run", &destination);
-        if (r < 0 || !PATH_IN_SET(destination, "../run", "/run"))
-                e = stpcpy(e, "var-run-bad:");
+        _cleanup_free_ char *destination = NULL;
+        if (readlink_malloc("/var/run", &destination) < 0 ||
+            !PATH_IN_SET(destination, "../run", "/run"))
+                stage[n++] = "var-run-bad";
 
-        r = read_one_line_file("/proc/sys/kernel/overflowuid", &overflowuid);
-        if (r >= 0 && !streq(overflowuid, "65534"))
-                e = stpcpy(e, "overflowuid-not-65534:");
-        r = read_one_line_file("/proc/sys/kernel/overflowgid", &overflowgid);
-        if (r >= 0 && !streq(overflowgid, "65534"))
-                e = stpcpy(e, "overflowgid-not-65534:");
+        _cleanup_free_ char *overflowuid = NULL, *overflowgid = NULL;
+        if (read_one_line_file("/proc/sys/kernel/overflowuid", &overflowuid) >= 0 &&
+            !streq(overflowuid, "65534"))
+                stage[n++] = "overflowuid-not-65534";
+        if (read_one_line_file("/proc/sys/kernel/overflowgid", &overflowgid) >= 0 &&
+            !streq(overflowgid, "65534"))
+                stage[n++] = "overflowgid-not-65534";
 
+        struct utsname uts;
         assert_se(uname(&uts) >= 0);
         if (strverscmp_improved(uts.release, KERNEL_BASELINE_VERSION) < 0)
-                e = stpcpy(e, "old-kernel:");
+                stage[n++] = "old-kernel";
 
         if (short_uid_range("/proc/self/uid_map") > 0)
-                e = stpcpy(e, "short-uid-range:");
+                stage[n++] = "short-uid-range";
         if (short_uid_range("/proc/self/gid_map") > 0)
-                e = stpcpy(e, "short-gid-range:");
+                stage[n++] = "short-gid-range";
 
-        /* remove the last ':' */
-        if (e != buf)
-                e[-1] = 0;
+        assert(n < ELEMENTSOF(stage) - 1);  /* One extra for NULL terminator */
 
-        return buf;
+        return strv_join((char**) stage, ":");
 }
 
 void manager_ref_console(Manager *m) {

src/core/manager.h

@@ -551,7 +551,7 @@ int manager_ref_uid(Manager *m, uid_t uid, bool clean_ipc);
 void manager_unref_gid(Manager *m, gid_t gid, bool destroy_now);
 int manager_ref_gid(Manager *m, gid_t gid, bool clean_ipc);
 
-char *manager_taint_string(Manager *m);
+char* manager_taint_string(const Manager *m);
 
 void manager_ref_console(Manager *m);
 void manager_unref_console(Manager *m);

src/partition/test-repart.sh

@@ -201,7 +201,7 @@ $D/zzz7 : start=     6291416, size=       98304, type=0FC63DAF-8483-4772-8E79-3D
 EOF
 
     LOOP="$(losetup -P --show --find "$D/zzz")"
-    "${udevadm:?}" wait --timeout 60 --initialized=yes --settle "${LOOP:?}"
+    "${udevadm:?}" wait --timeout 60 --settle "${LOOP:?}"
 
     VOLUME="test-repart-$RANDOM"
 

src/shared/devnode-acl.c

@@ -9,9 +9,9 @@
 #include "device-util.h"
 #include "devnode-acl.h"
 #include "dirent-util.h"
-#include "escape.h"
 #include "fd-util.h"
 #include "format-util.h"
+#include "fs-util.h"
 #include "set.h"
 #include "string-util.h"
 #include "util.h"
@@ -195,21 +195,18 @@ int devnode_acl_all(const char *seat,
         dir = opendir("/run/udev/static_node-tags/uaccess");
         if (dir) {
                 FOREACH_DIRENT(de, dir, return -errno) {
-                        _cleanup_free_ char *unescaped_devname = NULL;
-                        ssize_t l;
-
-                        l = cunescape(de->d_name, UNESCAPE_RELAX, &unescaped_devname);
-                        if (l < 0)
-                                return l;
-
-                        n = path_join("/dev", unescaped_devname);
-                        if (!n)
-                                return -ENOMEM;
+                        r = readlinkat_malloc(dirfd(dir), de->d_name, &n);
+                        if (r == -ENOENT)
+                                continue;
+                        if (r < 0) {
+                                log_debug_errno(r,
+                                                "Unable to read symlink '/run/udev/static_node-tags/uaccess/%s', ignoring: %m",
+                                                de->d_name);
+                                continue;
+                        }
 
                         log_debug("Found static node %s for seat %s", n, seat);
                         r = set_consume(nodes, n);
-                        if (r == -EEXIST)
-                                continue;
                         if (r < 0)
                                 return r;
                 }

src/shutdown/umount.c

@@ -352,9 +352,14 @@ static int md_list_get(MountPoint **head) {
         if (r < 0)
                 return r;
 
+        /* Filter out partitions. */
+        r = sd_device_enumerator_add_match_property(e, "DEVTYPE", "disk");
+        if (r < 0)
+                return r;
+
         FOREACH_DEVICE(e, d) {
                 _cleanup_free_ char *p = NULL;
-                const char *dn;
+                const char *dn, *md_level;
                 MountPoint *m;
                 dev_t devnum;
 
@@ -362,6 +367,17 @@ static int md_list_get(MountPoint **head) {
                     sd_device_get_devname(d, &dn) < 0)
                         continue;
 
+                r = sd_device_get_property_value(d, "MD_LEVEL", &md_level);
+                if (r < 0) {
+                        log_warning_errno(r, "Failed to get MD_LEVEL property for %s, ignoring: %m", dn);
+                        continue;
+                }
+
+                /* MD "containers" are a special type of MD devices, used for external metadata.
+                 * Since it doesn't provide RAID functionality in itself we don't need to stop it. */
+                if (streq(md_level, "container"))
+                        continue;
+
                 p = strdup(dn);
                 if (!p)
                         return -ENOMEM;

src/test/meson.build

@@ -56,6 +56,12 @@ tests += [
           libblkid],
          core_includes],
 
+        [files('test-manager.c'),
+         [libcore,
+          libshared],
+         [],
+         core_includes],
+
         [files('test-emergency-action.c'),
          [libcore,
           libshared],

src/test/test-manager.c

@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "manager.h"
+#include "tests.h"
+
+TEST(manager_taint_string) {
+        Manager m = {};
+
+        _cleanup_free_ char *a = manager_taint_string(&m);
+        assert_se(a);
+        log_debug("taint string w/o split-usr: '%s'", a);
+        /* split-usr is the only one that is cached in Manager, so we know it's not present.
+         * The others are queried dynamically, so we'd need to duplicate the logic here
+         * to test for them. Let's do just one. */
+        assert_se(!strstr(a, "split-usr"));
+
+        if (cg_all_unified() == 0)
+                assert_se(strstr(a, "cgroupsv1"));
+        else
+                assert_se(!strstr(a, "cgroupsv1"));
+
+        m.taint_usr = true;
+        _cleanup_free_ char *b = manager_taint_string(&m);
+        assert_se(b);
+        log_debug("taint string w/ split-usr: '%s'", b);
+        assert_se(strstr(b, "split-usr"));
+}
+
+DEFINE_TEST_MAIN(LOG_DEBUG);

src/udev/udevd.c

@@ -442,6 +442,12 @@ static int device_get_whole_disk(sd_device *dev, sd_device **ret_device, const c
         if (r < 0)
                 return log_device_debug_errno(dev, r, "Failed to get sysname: %m");
 
+        /* Exclude the following devices:
+         * For "dm-", see the comment added by e918a1b5a94f270186dca59156354acd2a596494.
+         * For "md", see the commit message of 2e5b17d01347d3c3118be2b8ad63d20415dbb1f0,
+         * but not sure the assumption is still valid even when partitions are created on the md
+         * devices, surprisingly which seems to be possible, see PR #22973.
+         * For "drbd", see the commit message of fee854ee8ccde0cd28e0f925dea18cce35f3993d. */
         if (STARTSWITH_SET(val, "dm-", "md", "drbd"))
                 goto irrelevant;
 

test/units/testsuite-58.sh

@@ -173,20 +173,22 @@ rm -r /tmp/testsuite-58.3-defs/
 # testcase for #21817
 mkdir -p /tmp/testsuite-58-issue-21817-defs/
 truncate -s 100m /var/tmp/testsuite-58-issue-21817.img
-LOOP=$(losetup -P --show -f /var/tmp/testsuite-58-issue-21817.img)
-udevadm wait --timeout 60 --initialized=yes --settle "${LOOP:?}"
-printf 'size=50M,type=%s\n,\n' "${root_guid}" | sfdisk -X gpt "$LOOP"
+sfdisk /var/tmp/testsuite-58-issue-21817.img <<EOF
+label: gpt
+
+size=50M, type=${root_guid}
+,
+EOF
 cat >/tmp/testsuite-58-issue-21817-defs/test.conf <<EOF
 [Partition]
 Type=root
 EOF
-systemd-repart --pretty=yes --definitions /tmp/testsuite-58-issue-21817-defs/ "$LOOP"
-sfdisk --dump "$LOOP" | tee /tmp/testsuite-58-issue-21817.dump
-losetup -d "$LOOP"
+systemd-repart --pretty=yes --definitions /tmp/testsuite-58-issue-21817-defs/ --dry-run=no /var/tmp/testsuite-58-issue-21817.img
+sfdisk --dump /var/tmp/testsuite-58-issue-21817.img | tee /tmp/testsuite-58-issue-21817.dump
 
-grep -qiF "p1 : start=        2048, size=      102400, type=${root_guid}," /tmp/testsuite-58-issue-21817.dump
+grep -qiF "/var/tmp/testsuite-58-issue-21817.img1 : start=        2048, size=      102400, type=${root_guid}," /tmp/testsuite-58-issue-21817.dump
 # Accept both unpadded (pre-v2.38 util-linux) and padded (v2.38+ util-linux) sizes
-grep -qE "p2 : start=      104448, size=      (100319| 98304)," /tmp/testsuite-58-issue-21817.dump
+grep -qE "/var/tmp/testsuite-58-issue-21817.img2 : start=      104448, size=      (100319| 98304)," /tmp/testsuite-58-issue-21817.dump
 
 rm /var/tmp/testsuite-58-issue-21817.img /tmp/testsuite-58-issue-21817.dump
 rm -r /tmp/testsuite-58-issue-21817-defs/
@@ -216,7 +218,7 @@ EOF
 
     truncate -s 100m "/tmp/testsuite-58-sector-$1.img"
     LOOP=$(losetup -b "$1" -P --show -f "/tmp/testsuite-58-sector-$1.img" )
-    udevadm wait --timeout 60 --initialized=yes --settle "${LOOP:?}"
+    udevadm wait --timeout 60 --settle "${LOOP:?}"
     systemd-repart --pretty=yes --definitions=/tmp/testsuite-58-sector/ --seed=750b6cd5c4ae4012a15e7be3c29e6a47 --empty=require --dry-run=no "$LOOP"
     rm -rf /tmp/testsuite-58-sector
     sfdisk --verify "$LOOP"

test/units/testsuite-64.sh

@@ -168,7 +168,7 @@ $(printf 'name="test%d", size=2M\n' {1..50})
 EOF
 
     # Initial partition table
-    sfdisk -q -X gpt "$blockdev" <"$partscript"
+    udevadm lock --device="$blockdev" sfdisk -q -X gpt "$blockdev" <"$partscript"
 
     # Delete the partitions, immediately recreate them, wait for udev to settle
     # down, and then check if we have any dangling symlinks in /dev/disk/. Rinse
@@ -177,8 +177,8 @@ EOF
     # On unpatched udev versions the delete-recreate cycle may trigger a race
     # leading to dead symlinks in /dev/disk/
     for i in {1..100}; do
-        sfdisk -q --delete "$blockdev"
-        sfdisk -q -X gpt "$blockdev" <"$partscript"
+        udevadm lock --device="$blockdev" sfdisk -q --delete "$blockdev"
+        udevadm lock --device="$blockdev" sfdisk -q -X gpt "$blockdev" <"$partscript"
 
         if ((i % 10 == 0)); then
             udevadm wait --settle --timeout=30 "$blockdev"
@@ -281,7 +281,7 @@ testcase_btrfs_basic() {
     echo "Multiple devices: using partitions, data: single, metadata: raid1"
     uuid="deadbeef-dead-dead-beef-000000000001"
     label="btrfs_mpart"
-    sfdisk --wipe=always "${devices[0]}" <<EOF
+    udevadm lock --device="${devices[0]}" sfdisk --wipe=always "${devices[0]}" <<EOF
 label: gpt
 
 name="diskpart1", size=85M