sys-apps/systemd: Apply Flatcar patches

Signed-off-by: Sayan Chowdhury <schowdhury@microsoft.com>
2025-08-18 02:16:59 +02:00 · 2021-09-02 09:04:56 +00:00 · 2021-09-02 09:04:56 +00:00 · 043ef47f5b
commit 043ef47f5b
parent ff243aa613
10 changed files with 484 additions and 66 deletions
--- a/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0004-wait-online-set-any-by-default.patch
+++ b/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0004-wait-online-set-any-by-default.patch
@ -0,0 +1,32 @@
+From eb00b0bf1014fd9da26fc1ed2612c579cbcf09ce Mon Sep 17 00:00:00 2001
+From: David Michael <dm0@redhat.com>
+Date: Tue, 16 Apr 2019 02:44:51 +0000
+Subject: [PATCH 1/5] wait-online: set --any by default
+
+The systemd-networkd-wait-online command would normally continue
+waiting after a network interface is usable if other interfaces are
+still configuring.  There is a new flag --any to change this.
+
+Preserve previous Container Linux behavior for compatibility by
+setting the --any flag by default.  See patches from v241 (or
+earlier) for the original implementation.
+---
+ src/network/wait-online/wait-online.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/network/wait-online/wait-online.c b/src/network/wait-online/wait-online.c
+index 1b24b6f1a6..dedbd50725 100644
+--- a/src/network/wait-online/wait-online.c
+++ b/src/network/wait-online/wait-online.c
+@@ -20,7 +20,7 @@ static Hashmap *arg_interfaces = NULL;
+ static char **arg_ignore = NULL;
+ static LinkOperationalStateRange arg_required_operstate = { _LINK_OPERSTATE_INVALID, _LINK_OPERSTATE_INVALID };
+ static AddressFamily arg_required_family = ADDRESS_FAMILY_NO;
+-static bool arg_any = false;
+static bool arg_any = true;
+
+ STATIC_DESTRUCTOR_REGISTER(arg_interfaces, hashmap_free_free_freep);
+ STATIC_DESTRUCTOR_REGISTER(arg_ignore, strv_freep);
+--
+2.30.2
+
--- a/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0005-networkd-default-to-kernel-IPForwarding-setting.patch
+++ b/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0005-networkd-default-to-kernel-IPForwarding-setting.patch
@ -0,0 +1,24 @@
+From 9acb14187bacd1d716adaed491813ea1cde12237 Mon Sep 17 00:00:00 2001
+From: Nick Owens <nick.owens@coreos.com>
+Date: Tue, 2 Jun 2015 18:22:32 -0700
+Subject: [PATCH 2/5] networkd: default to "kernel" IPForwarding setting
+
+---
+ src/network/networkd-network.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/src/network/networkd-network.c b/src/network/networkd-network.c
+index 850b4f449e..951c2d0815 100644
+--- a/src/network/networkd-network.c
+++ b/src/network/networkd-network.c
+@@ -398,6 +398,7 @@ int network_load_one(Manager *manager, OrderedHashmap **networks, const char *fi
+                 .ipv6ll_address_gen_mode = _IPV6_LINK_LOCAL_ADDRESS_GEN_MODE_INVALID,
+
+                 .ipv4_accept_local = -1,
+                .ip_forward = _ADDRESS_FAMILY_INVALID,
+                 .ipv4_route_localnet = -1,
+                 .ipv6_privacy_extensions = IPV6_PRIVACY_EXTENSIONS_NO,
+                 .ipv6_accept_ra = -1,
+--
+2.30.2
+
--- a/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0006-needs-update-don-t-require-strictly-newer-usr.patch
+++ b/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0006-needs-update-don-t-require-strictly-newer-usr.patch
@ -0,0 +1,58 @@
+From e073ce40241db173d160d5d9986129820a98270a Mon Sep 17 00:00:00 2001
+From: Alex Crawford <alex.crawford@coreos.com>
+Date: Wed, 2 Mar 2016 10:46:33 -0800
+Subject: [PATCH 3/5] needs-update: don't require strictly newer usr
+
+Updates should be triggered whenever usr changes, not only when it is newer.
+---
+ man/systemd-update-done.service.xml | 2 +-
+ src/shared/condition.c              | 6 +++---
+ 2 files changed, 4 insertions(+), 4 deletions(-)
+
+diff --git a/man/systemd-update-done.service.xml b/man/systemd-update-done.service.xml
+index 3393010ff6..5478baca25 100644
+--- a/man/systemd-update-done.service.xml
+++ b/man/systemd-update-done.service.xml
+@@ -50,7 +50,7 @@
+     <varname>ConditionNeedsUpdate=</varname> (see
+     <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>)
+     condition to make sure to run when <filename>/etc/</filename> or
+-    <filename>/var/</filename> are older than <filename>/usr/</filename>
+    <filename>/var/</filename> aren't the same age as <filename>/usr/</filename>
+     according to the modification times of the files described above.
+     This requires that updates to <filename>/usr/</filename> are always
+     followed by an update of the modification time of
+diff --git a/src/shared/condition.c b/src/shared/condition.c
+index b2ec690bc3..4cf6523b90 100644
+--- a/src/shared/condition.c
+++ b/src/shared/condition.c
+@@ -593,7 +593,7 @@ static int condition_test_needs_update(Condition *c, char **env) {
+          * First, compare seconds as they are always accurate...
+          */
+         if (usr.st_mtim.tv_sec != other.st_mtim.tv_sec)
+-                return usr.st_mtim.tv_sec > other.st_mtim.tv_sec;
+                return true;
+
+         /*
+          * ...then compare nanoseconds.
+@@ -604,7 +604,7 @@ static int condition_test_needs_update(Condition *c, char **env) {
+          * (otherwise the filesystem supports nsec timestamps, see stat(2)).
+          */
+         if (usr.st_mtim.tv_nsec == 0 || other.st_mtim.tv_nsec > 0)
+-                return usr.st_mtim.tv_nsec > other.st_mtim.tv_nsec;
+                return usr.st_mtim.tv_nsec != other.st_mtim.tv_nsec;
+
+         _cleanup_free_ char *timestamp_str = NULL;
+         r = parse_env_file(NULL, p, "TIMESTAMP_NSEC", &timestamp_str);
+@@ -623,7 +623,7 @@ static int condition_test_needs_update(Condition *c, char **env) {
+                 return true;
+         }
+
+-        return timespec_load_nsec(&usr.st_mtim) > timestamp;
+        return timespec_load_nsec(&usr.st_mtim) != timestamp;
+ }
+
+ static int condition_test_first_boot(Condition *c, char **env) {
+--
+2.26.2
+
--- a/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0007-core-use-max-for-DefaultTasksMax.patch
+++ b/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0007-core-use-max-for-DefaultTasksMax.patch
@ -0,0 +1,65 @@
+From 3acaafc6fcd34b272e5249c49e498ff7facb564e Mon Sep 17 00:00:00 2001
+From: Sayan Chowdhury <sayan@kinvolk.io>
+Date: Thu, 22 Apr 2021 20:08:33 +0530
+Subject: [PATCH] core: use max for DefaultTasksMax
+
+Since systemd v228, systemd has a DefaultTasksMax which defaulted
+to 512, later 15% of the system's maximum number of PIDs.  This
+limit is low and a change in behavior that people running services
+in containers will hit frequently, so revert to previous behavior.
+
+Though later the TasksMax was changed in the a dynamic property to
+accommodate stale values.
+
+This change is built on previous patch by David Michael(dm0-).
+
+Signed-off-by: Sayan Chowdhury <sayan@kinvolk.io>
+---
+ man/systemd-system.conf.xml | 2 +-
+ src/core/main.c             | 2 +-
+ src/core/system.conf.in     | 2 +-
+ 3 files changed, 3 insertions(+), 3 deletions(-)
+
+diff --git a/man/systemd-system.conf.xml b/man/systemd-system.conf.xml
+index d39928ec23..4d89a68b16 100644
+--- a/man/systemd-system.conf.xml
+++ b/man/systemd-system.conf.xml
+@@ -376,7 +376,7 @@
+         <listitem><para>Configure the default value for the per-unit <varname>TasksMax=</varname> setting. See
+         <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+         for details. This setting applies to all unit types that support resource control settings, with the exception
+-        of slice units. Defaults to 15% of the minimum of <varname>kernel.pid_max=</varname>, <varname>kernel.threads-max=</varname>
+        of slice units. Defaults to 100% of the minimum of <varname>kernel.pid_max=</varname>, <varname>kernel.threads-max=</varname>
+         and root cgroup <varname>pids.max</varname>.
+         Kernel has a default value for <varname>kernel.pid_max=</varname> and an algorithm of counting in case of more than 32 cores.
+         For example with the default <varname>kernel.pid_max=</varname>, <varname>DefaultTasksMax=</varname> defaults to 4915,
+diff --git a/src/core/main.c b/src/core/main.c
+index 0ddd629851..5e25a1b4b7 100644
+--- a/src/core/main.c
+++ b/src/core/main.c
+@@ -91,7 +91,7 @@
+ #include <sanitizer/lsan_interface.h>
+ #endif
+ 
+-#define DEFAULT_TASKS_MAX ((TasksMax) { 15U, 100U }) /* 15% */
+#define DEFAULT_TASKS_MAX ((TasksMax) { 100U, 100U }) /* 100% */
+ 
+ static enum {
+         ACTION_RUN,
+diff --git a/src/core/system.conf.in b/src/core/system.conf.in
+index fa6fb690c7..1e6df17d94 100644
+--- a/src/core/system.conf.in
+++ b/src/core/system.conf.in
+@@ -55,7 +55,7 @@
+ #DefaultBlockIOAccounting=no
+ #DefaultMemoryAccounting=@MEMORY_ACCOUNTING_DEFAULT@
+ #DefaultTasksAccounting=yes
+-#DefaultTasksMax=15%
+#DefaultTasksMax=100%
+ #DefaultLimitCPU=
+ #DefaultLimitFSIZE=
+ #DefaultLimitDATA=
+-- 
+2.30.2
+
+
--- a/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0008-systemd-Disable-SELinux-permissions-checks.patch
+++ b/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0008-systemd-Disable-SELinux-permissions-checks.patch
@ -0,0 +1,29 @@
+From f83a1a190139d6f7752e0d7c86396330f845b261 Mon Sep 17 00:00:00 2001
+From: Matthew Garrett <mjg59@coreos.com>
+Date: Tue, 20 Dec 2016 16:43:22 +0000
+Subject: [PATCH 5/5] systemd: Disable SELinux permissions checks
+
+We don't care about the interaction between systemd and SELinux policy, so
+let's just disable these checks rather than having to incorporate policy
+support. This has no impact on our SELinux use-case, which is purely intended
+to limit containers and not anything running directly on the host.
+---
+ src/core/selinux-access.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/core/selinux-access.c b/src/core/selinux-access.c
+index 1d52b5ff04..1653d241f6 100644
+--- a/src/core/selinux-access.c
+++ b/src/core/selinux-access.c
+@@ -2,7 +2,7 @@
+ 
+ #include "selinux-access.h"
+ 
+-#if HAVE_SELINUX
+#if 0
+ 
+ #include <errno.h>
+ #include <selinux/avc.h>
+-- 
+2.26.2
+
--- a/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0009-core-handle-lookup-paths-being-symlinks.patch
+++ b/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/0009-core-handle-lookup-paths-being-symlinks.patch
@ -0,0 +1,84 @@
+From 67d9962aa637401a1332069b6c8ad99a54e2b451 Mon Sep 17 00:00:00 2001
+From: Sayan Chowdhury <sayan@kinvolk.io>
+Date: Wed, 8 Sep 2021 12:10:35 +0530
+Subject: [PATCH] core: handle lookup paths being symlinks
+
+With a recent change paths leaving the statically known lookup paths
+would be treated differently then those that remained within those. That
+was done (AFAIK) to consistently handle alias names. Unfortunately that
+means that on some distributions, especially those where /etc/ consists
+mostly of symlinks, would trigger that new detection for every single
+unit in /etc/systemd/system. The reason for that is that the units
+directory itself is already a symlink.
+
+Original Patch from: https://github.com/systemd/systemd/pull/20479
+
+Signed-off-by: Sayan Chowdhury <sayan@kinvolk.io>
+---
+ src/basic/unit-file.c | 33 +++++++++++++++++++++++++++++++--
+ 1 file changed, 31 insertions(+), 2 deletions(-)
+
+diff --git a/src/basic/unit-file.c b/src/basic/unit-file.c
+index 884a0674a9..3ae2a115d0 100644
+--- a/src/basic/unit-file.c
+++ b/src/basic/unit-file.c
+@@ -254,6 +254,7 @@ int unit_file_build_name_map(
+ 
+         _cleanup_hashmap_free_ Hashmap *ids = NULL, *names = NULL;
+         _cleanup_set_free_free_ Set *paths = NULL;
+        _cleanup_strv_free_ char **expanded_search_paths = NULL;
+         uint64_t timestamp_hash;
+         char **dir;
+         int r;
+@@ -273,6 +274,34 @@ int unit_file_build_name_map(
+                         return log_oom();
+         }
+ 
+        /* Go over all our search paths, chase their symlinks and store the
+         * result in the expanded_search_paths list.
+         *
+         * This is important for cases where any of the unit directories itself
+         * are symlinks into other directories and would therefore cause all of
+         * the unit files to be recognized as linked units.
+         *
+         * This is important for distributions such as NixOS where most paths
+         * in /etc/ are symlinks to some other location on the filesystem (e.g.
+         * into /nix/store/).
+         */
+        STRV_FOREACH(dir, (char**) lp->search_path) {
+                _cleanup_free_ char *resolved_dir = NULL;
+                r = strv_extend(&expanded_search_paths, *dir);
+                if (r < 0)
+                        return log_oom();
+
+                r = chase_symlinks(*dir, NULL, 0, &resolved_dir, NULL);
+                if (r < 0) {
+                        if (r != -ENOENT)
+                                log_warning_errno(r, "Failed to resolve symlink %s, ignoring: %m", *dir);
+                        continue;
+                }
+
+                if (strv_consume(&expanded_search_paths, TAKE_PTR(resolved_dir)) < 0)
+                        return log_oom();
+        }
+
+         STRV_FOREACH(dir, (char**) lp->search_path) {
+                 struct dirent *de;
+                 _cleanup_closedir_ DIR *d = NULL;
+@@ -351,11 +380,11 @@ int unit_file_build_name_map(
+                                         continue;
+                                 }
+ 
+-                                /* Check if the symlink goes outside of our search path.
+                                /* Check if the symlink goes outside of our (expanded) search path.
+                                  * If yes, it's a linked unit file or mask, and we don't care about the target name.
+                                  * Let's just store the link source directly.
+                                  * If not, let's verify that it's a good symlink. */
+-                                char *tail = path_startswith_strv(simplified, lp->search_path);
+                                char *tail = path_startswith_strv(simplified, expanded_search_paths);
+                                 if (!tail) {
+                                         log_debug("%s: linked unit file: %s → %s",
+                                                   __func__, filename, simplified);
+-- 
+2.30.2
+
--- a/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/99-default.preset
+++ b/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/99-default.preset
@ -0,0 +1,2 @@
+# Do not enable any services if /etc is detected as empty.
+disable *
--- a/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/systemd-flatcar.conf
+++ b/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/systemd-flatcar.conf
@ -0,0 +1,14 @@
+d   /etc/binfmt.d           -   -   -   -   -
+d   /etc/kernel/install.d   -   -   -   -   -
+d   /etc/modules-load.d     -   -   -   -   -
+d   /etc/sysctl.d           -   -   -   -   -
+d   /etc/systemd            -   -   -   -   -
+d   /etc/systemd/network    -   -   -   -   -
+d   /etc/systemd/system     -   -   -   -   -
+d   /etc/systemd/user       -   -   -   -   -
+d   /etc/tmpfiles.d         -   -   -   -   -
+d   /etc/sysusers.d         -   -   -   -   -
+d   /etc/udev/hwdb.d        -   -   -   -   -
+d   /etc/udev/rules.d       -   -   -   -   -
+d   /var/lib/systemd        -   -   -   -   -
+d   /var/log/journal/remote -   systemd-journal-remote   systemd-journal-remote   -   -
--- a/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/systemd-resolv.conf
+++ b/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/files/systemd-resolv.conf
@ -0,0 +1,2 @@
+d   /run/systemd/network                -   -   -   -   -
+L   /run/systemd/network/resolv.conf    -   -   -   -   ../resolve/resolv.conf
--- a/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/systemd-9999.ebuild
+++ b/sdk_container/src/third_party/coreos-overlay/sys-apps/systemd/systemd-9999.ebuild
@ -2,7 +2,8 @@
 # Distributed under the terms of the GNU General Public License v2

 EAPI=7
-PYTHON_COMPAT=( python3_{8..10} )
+# Flatcar: We still have python 3.6.
+PYTHON_COMPAT=( python3_{5,6,7} )

 if [[ ${PV} == 9999 ]]; then
 	EGIT_REPO_URI="https://github.com/systemd/systemd.git"
@ -17,17 +18,19 @@ else
 	MY_P=${MY_PN}-${MY_PV}
 	S=${WORKDIR}/${MY_P}
 	SRC_URI="https://github.com/systemd/${MY_PN}/archive/v${MY_PV}/${MY_P}.tar.gz"
-	KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~hppa ~ia64 ~mips ~ppc ~ppc64 ~riscv ~sparc ~x86"
+	KEYWORDS="~alpha amd64 arm arm64 ~hppa ~ia64 ~mips ppc ppc64 ~riscv sparc x86"
 fi

-inherit bash-completion-r1 linux-info meson-multilib pam python-any-r1 systemd toolchain-funcs udev usr-ldscript
+# Flatcar: We don't use gen_usr_ldscript so dropping usr-ldscript
+inherit bash-completion-r1 linux-info meson-multilib pam python-any-r1 systemd toolchain-funcs udev user

 DESCRIPTION="System and service manager for Linux"
 HOMEPAGE="https://www.freedesktop.org/wiki/Software/systemd"

 LICENSE="GPL-2 LGPL-2.1 MIT public-domain"
 SLOT="0/2"
-IUSE="acl apparmor audit build cgroup-hybrid cryptsetup curl dns-over-tls elfutils +gcrypt gnuefi homed http +hwdb idn importd +kmod +lz4 lzma nat pam pcre pkcs11 policykit pwquality qrcode repart +resolvconf +seccomp selinux split-usr static-libs +sysv-utils test tpm vanilla xkb +zstd"
+# Flatcar: Dropped static-libs, we don't care about static libraries.
+IUSE="acl apparmor audit build cgroup-hybrid cryptsetup curl dns-over-tls elfutils +gcrypt gnuefi homed http +hwdb idn importd +kmod +lz4 lzma nat pam pcre pkcs11 policykit pwquality qrcode repart +resolvconf +seccomp selinux split-usr +sysv-utils test tpm vanilla xkb +zstd"

 REQUIRED_USE="
 	homed? ( cryptsetup pam )
@ -84,35 +87,22 @@ DEPEND="${COMMON_DEPEND}
 	gnuefi? ( >=sys-boot/gnu-efi-3.0.2 )
 "

-# baselayout-2.2 has /run
+# Flatcar: We drop a few of the acct-group and acct-user as the gid provided by
+# the upstream does not match with the ones we carry in baselayout.
 RDEPEND="${COMMON_DEPEND}
 	>=acct-group/adm-0-r1
 	>=acct-group/wheel-0-r1
 	>=acct-group/kmem-0-r1
 	>=acct-group/tty-0-r1
 	>=acct-group/utmp-0-r1
-	>=acct-group/audio-0-r1
-	>=acct-group/cdrom-0-r1
-	>=acct-group/dialout-0-r1
-	>=acct-group/disk-0-r1
-	>=acct-group/input-0-r1
 	>=acct-group/kvm-0-r1
-	>=acct-group/lp-0-r1
-	>=acct-group/render-0-r1
 	acct-group/sgx
-	>=acct-group/tape-0-r1
 	acct-group/users
-	>=acct-group/video-0-r1
-	>=acct-group/systemd-journal-0-r1
 	>=acct-user/root-0-r1
 	acct-user/nobody
-	>=acct-user/systemd-journal-remote-0-r1
 	>=acct-user/systemd-coredump-0-r1
-	>=acct-user/systemd-network-0-r1
 	acct-user/systemd-oom
-	>=acct-user/systemd-resolve-0-r1
 	>=acct-user/systemd-timesync-0-r1
-	>=sys-apps/baselayout-2.2
 	selinux? ( sec-policy/selinux-base-policy[systemd] )
 	sysv-utils? (
 		!sys-apps/openrc[sysv-utils(-)]
@ -131,9 +121,10 @@ RDEPEND="${COMMON_DEPEND}
 "

 # sys-apps/dbus: the daemon only (+ build-time lib dep for tests)
+#
+# Flatcar: We don't have sys-fs/udev-init-scripts-34, so it's dropped.
 PDEPEND=">=sys-apps/dbus-1.9.8[systemd]
 	hwdb? ( sys-apps/hwids[systemd(+),udev] )
-	>=sys-fs/udev-init-scripts-34
 	policykit? ( sys-auth/polkit )
 	!vanilla? ( sys-apps/gentoo-systemd-integration )"

@ -222,15 +213,27 @@ src_prepare() {

 	# Add local patches here
 	PATCHES+=(
+		# Flatcar: Adding our own patches here.
+		"${FILESDIR}/249-libudev-static.patch"
+		"${FILESDIR}/0004-wait-online-set-any-by-default.patch"
+		"${FILESDIR}/0005-networkd-default-to-kernel-IPForwarding-setting.patch"
+		"${FILESDIR}/0006-needs-update-don-t-require-strictly-newer-usr.patch"
+		"${FILESDIR}/0007-core-use-max-for-DefaultTasksMax.patch"
+		"${FILESDIR}/0008-systemd-Disable-SELinux-permissions-checks.patch"
+		"${FILESDIR}/0009-core-handle-lookup-paths-being-symlinks.patch"
 	)

-	if ! use vanilla; then
-		PATCHES+=(
-			"${FILESDIR}/gentoo-generator-path-r2.patch"
-			"${FILESDIR}/gentoo-systemctl-disable-sysv-sync-r1.patch"
-			"${FILESDIR}/gentoo-journald-audit.patch"
-		)
-	fi
+	# Flatcar: We carry our own patches, we don't use the ones
+	# from Gentoo. Thus we dropped the `if ! use vanilla` code
+	# here.
+
+	# Flatcar: The Kubelet takes /etc/resolv.conf for, e.g., CoreDNS which has dnsPolicy "default", but unless
+	# the kubelet --resolv-conf flag is set to point to /run/systemd/resolve/resolv.conf this won't work with
+	# /etc/resolv.conf pointing to /run/systemd/resolve/stub-resolv.conf which configures 127.0.0.53.
+	# See https://kubernetes.io/docs/tasks/administer-cluster/dns-debugging-resolution/#known-issues
+	# This means that users who need split DNS to work should point /etc/resolv.conf back to /run/systemd/resolve/stub-resolv.conf
+	# (and if using K8s configure the kubelet resolvConf variable/--resolv-conf flag to /run/systemd/resolve/resolv.conf).
+	sed -i -e 's,/run/systemd/resolve/stub-resolv.conf,/run/systemd/resolve/resolv.conf,' tmpfiles.d/etc.conf.in || die

 	default
 }
@ -247,7 +250,8 @@ src_configure() {
 multilib_src_configure() {
 	local myconf=(
 		--localstatedir="${EPREFIX}/var"
-		-Dsupport-url="https://gentoo.org/support/"
+		# Flatcar: Point to our user mailing list.
+		-Dsupport-url="https://groups.google.com/forum/#!forum/flatcar-linux-user"
 		-Dpamlibdir="$(getpam_mod_dir)"
 		# avoid bash-completion dep
 		-Dbashcompletiondir="$(get_bashcompdir)"
@ -258,7 +262,6 @@ multilib_src_configure() {
 		-Drootlibdir="${EPREFIX}/usr/$(get_libdir)"
 		# Avoid infinite exec recursion, bug 642724
 		-Dtelinit-path="${EPREFIX}/lib/sysvinit/telinit"
-		# no deps
 		-Dima=true
 		-Ddefault-hierarchy=$(usex cgroup-hybrid hybrid unified)
 		# Optional components/dependencies
@ -298,9 +301,11 @@ multilib_src_configure() {
 		$(meson_native_use_bool tpm tpm2)
 		$(meson_native_use_bool test dbus)
 		$(meson_native_use_bool xkb xkbcommon)
-		-Dntp-servers="0.gentoo.pool.ntp.org 1.gentoo.pool.ntp.org 2.gentoo.pool.ntp.org 3.gentoo.pool.ntp.org"
+		# Flatcar: Use our ntp servers.
+		-Dntp-servers="0.flatcar.pool.ntp.org 1.flatcar.pool.ntp.org 2.flatcar.pool.ntp.org 3.flatcar.pool.ntp.org"
 		# Breaks screen, tmux, etc.
 		-Ddefault-kill-user-processes=false
+		# Flatcar: TODO: Investigate if we want this.
 		-Dcreate-log-dirs=false

 		# multilib options
@ -324,8 +329,42 @@ multilib_src_configure() {
 		$(meson_native_true tmpfiles)
 		$(meson_native_true vconsole)

-		# static-libs
-		$(meson_use static-libs static-libudev)
+		# Flatcar: Specify this, or meson breaks due to no
+		# /etc/login.defs.
+		-Dsystem-gid-max=999
+		-Dsystem-uid-max=999
+
+		# Flatcar: DBus paths.
+		-Ddbussessionservicedir="${EPREFIX}/usr/share/dbus-1/services"
+		-Ddbussystemservicedir="${EPREFIX}/usr/share/dbus-1/system-services"
+
+		# Flatcar: PAM config directory.
+		-Dpamconfdir=/usr/share/pam.d
+
+		# Flatcar: The CoreOS epoch, Mon Jul 1 00:00:00 UTC
+		# 2013. Used by timesyncd as a sanity check for the
+		# minimum acceptable time. Explicitly set to avoid
+		# using the current build time.
+		-Dtime-epoch=1372636800
+
+		# Flatcar: No default name servers.
+		-Ddns-servers=
+
+		# Flatcar: Disable the "First Boot Wizard", it isn't
+		# very applicable to us.
+		-Dfirstboot=false
+
+		# Flatcar: Set latest network interface naming scheme
+		# for
+		# https://github.com/flatcar-linux/Flatcar/issues/36
+		-Ddefault-net-naming-scheme=latest
+
+		# Flatcar: Unported options, still needed?
+		-Defi-cc="$(tc-getCC)"
+		-Dquotaon-path=/usr/sbin/quotaon
+		-Dquotacheck-path=/usr/sbin/quotacheck
+
+		# Flatcar: No static libs.
 	)

 	meson_src_configure "${myconf[@]}"
@ -343,7 +382,8 @@ multilib_src_install_all() {
 	mv "${ED}"/usr/share/doc/{systemd,${PF}} || die

 	einstalldocs
-	dodoc "${FILESDIR}"/nsswitch.conf
+	# Flatcar: Do not install sample nsswitch.conf, we don't
+	# provide it.

 	if ! use resolvconf; then
 		rm -f "${ED}${rootprefix}"/sbin/resolvconf || die
@ -362,31 +402,11 @@ multilib_src_install_all() {
 		rmdir "${ED}${rootprefix}"/sbin || die
 	fi

-	# https://bugs.gentoo.org/761763
-	rm -r "${ED}"/usr/lib/sysusers.d || die
-
-	# Preserve empty dirs in /etc & /var, bug #437008
-	keepdir /etc/{binfmt.d,modules-load.d,tmpfiles.d}
-	keepdir /etc/kernel/install.d
-	keepdir /etc/systemd/{network,system,user}
-	keepdir /etc/udev/rules.d
-
-	if use hwdb; then
-		keepdir /etc/udev/hwdb.d
-	fi
-
-	keepdir "${rootprefix}"/lib/systemd/{system-sleep,system-shutdown}
-	keepdir /usr/lib/{binfmt.d,modules-load.d}
-	keepdir /usr/lib/systemd/user-generators
-	keepdir /var/lib/systemd
-	keepdir /var/log/journal
-
-	# Symlink /etc/sysctl.conf for easy migration.
-	dosym ../sysctl.conf /etc/sysctl.d/99-sysctl.conf
-
-	if use pam; then
-		newpamd "${FILESDIR}"/systemd-user.pam systemd-user
-	fi
+	# Flatcar: Upstream uses keepdir commands to keep some empty
+	# directories.
+	#
+	# Flatcar: TODO: Consider using that instead of
+	# systemd_dotmpfilesd "${FILESDIR}"/systemd-flatcar.conf below.

 	if use hwdb; then
 		rm -r "${ED}${rootprefix}"/lib/udev/hwdb.d || die
@ -398,7 +418,100 @@ multilib_src_install_all() {
 		dosym ../../../lib/systemd/systemd-shutdown /usr/lib/systemd/systemd-shutdown
 	fi

-	gen_usr_ldscript -a systemd udev
+	# Flatcar: Ensure journal directory has correct ownership/mode
+	# in inital image.  This is fixed by systemd-tmpfiles *but*
+	# journald starts before that and will create the journal if
+	# the filesystem is already read-write.  Conveniently the
+	# systemd Makefile sets this up completely wrong.
+	#
+	# Flatcar: TODO: Is this still a problem?
+	dodir /var/log/journal
+	fowners root:systemd-journal /var/log/journal
+	fperms 2755 /var/log/journal
+
+	# Flatcar: Don't prune systemd dirs.
+	#
+	# Flatcar: TODO: Upstream probably fixed it in different way -
+	# it's using some keepdir commands.
+	systemd_dotmpfilesd "${FILESDIR}"/systemd-flatcar.conf
+	# Flatcar: Add tmpfiles rule for resolv.conf. This path has
+	# changed after v213 so it must be handled here instead of
+	# baselayout now.
+	systemd_dotmpfilesd "${FILESDIR}"/systemd-resolv.conf
+
+	# Flatcar: Don't default to graphical.target.
+	local unitdir=$(builddir_systemd_get_systemunitdir)
+	dosym multi-user.target "${unitdir}"/default.target
+
+	# Flatcar: Don't set any extra environment variables by default.
+	rm "${ED}/usr/lib/environment.d/99-environment.conf" || die
+
+	# Flatcar: These lines more or less follow the systemd's
+	# preset file (90-systemd.preset). We do it that way, to avoid
+	# putting symlink in /etc. Please keep the lines in the same
+	# order as the "enable" lines appear in the preset file.
+	builddir_systemd_enable_service multi-user.target remote-fs.target
+	builddir_systemd_enable_service multi-user.target remote-cryptsetup.target
+	builddir_systemd_enable_service multi-user.target machines.target
+	# Flatcar: getty@.service is enabled manually below.
+	builddir_systemd_enable_service sysinit.target systemd-timesyncd.service
+	builddir_systemd_enable_service multi-user.target systemd-networkd.service
+	# Flatcar: For systemd-networkd.service, it has it in Also, which also
+	# needs to be enabled
+	builddir_systemd_enable_service sockets.target systemd-networkd.socket
+	# Flatcar: For systemd-networkd.service, it has it in Also, which also
+	# needs to be enabled
+	builddir_systemd_enable_service network-online.target systemd-networkd-wait-online.service
+	builddir_systemd_enable_service multi-user.target systemd-resolved.service
+	if use homed; then
+		builddir_systemd_enable_service multi-user.target systemd-homed.target
+		# Flatcar: systemd-homed.target has
+		# Also=systemd-userdbd.service, but the service has no
+		# WantedBy entry. It's likely going to be executed through
+		# systemd-userdbd.socket, which is enabled in upstream's
+		# presets file.
+		builddir_systemd_enable_service sockets.target systemd-userdbd.socket
+	fi
+	builddir_systemd_enable_service sysinit.target systemd-pstore.service
+	# Flatcar: not enabling reboot.target - it has no WantedBy
+	# entry.
+
+	# Flatcar: Enable getty manually.
+	dodir "${unitdir}/getty.target.wants"
+	dosym ../getty@.service "${unitdir}/getty.target.wants/getty@tty1.service"
+
+	# Flatcar: Use an empty preset file, because systemctl
+	# preset-all puts symlinks in /etc, not in /usr. We don't use
+	# /etc, because it is not autoupdated. We do the "preset" above.
+	rm "${ED}$(usex split-usr '' /usr)/lib/systemd/system-preset/90-systemd.preset" || die
+	insinto $(usex split-usr '' /usr)/lib/systemd/system-preset
+	doins "${FILESDIR}"/99-default.preset
+
+	# Flatcar: Do not ship distro-specific files (nsswitch.conf
+	# pam.d). This conflicts with our own configuration provided
+	# by baselayout.
+	rm -rf "${ED}"/usr/share/factory
+	sed -i "${ED}"/usr/lib/tmpfiles.d/etc.conf \
+		-e '/^C!* \/etc\/nsswitch\.conf/d' \
+		-e '/^C!* \/etc\/pam\.d/d' \
+		-e '/^C!* \/etc\/issue/d'
+
+	# Flatcar: gen_usr_ldscript is likely for static libs, so we
+	# dropped it.
+}
+
+builddir_systemd_enable_service() {
+    (
+        export SYSROOT="${ED}"
+        systemd_enable_service "$@"
+    )
+}
+
+builddir_systemd_get_systemunitdir() {
+    (
+        export SYSROOT="${ED}"
+        systemd_get_systemunitdir
+    )
 }

 migrate_locale() {
@ -478,13 +591,8 @@ pkg_postinst() {
 	# between OpenRC & systemd
 	migrate_locale

-	if [[ -z ${REPLACING_VERSIONS} ]]; then
-		if type systemctl &>/dev/null; then
-			systemctl --root="${ROOT:-/}" enable getty@.service remote-fs.target || FAIL=1
-		fi
-		elog "To enable a useful set of services, run the following:"
-		elog "  systemctl preset-all --preset-mode=enable-only"
-	fi
+	# Flatcar: We enable getty and remote-fs targets in /usr
+	# ourselves above.

 	if [[ -L ${EROOT}/var/lib/systemd/timesync ]]; then
 		rm "${EROOT}/var/lib/systemd/timesync"