[OE-core][dunfell][PATCH 1/2] systemd: implement --initialized-match/nomatch arguments

[pawan <badganchipv@gmail.com>]

systemd-udev-trigger.service by default triggeres all devices regardless
of whether they were already recognized by systemd-udevd.

There are machines (especially in embedded environments) where
systemd-udev-trigger.service is configured to run at a later stage of
the boot sequence, which can lead to quite a lot of devices being
triggered although they were already recognized by systemd-udevd.

Re-triggering a lot of devices is a relatively expensive operation and
therefore should be avoided if unnecessary.

Therefore this patch introduces --initialized-nomatch, which filters out
devices that are already present in the udev database. For consistance
reasons --initialized-match is implemented as well, which filters out devices
that are *not* already present in the udev database.

Signed-off-by: Pawan Badganchi <badganchipv@gmail.com>
---
 ...-initialized-match-nomatch-arguments.patch | 156 ++++++++++++++++++
 meta/recipes-core/systemd/systemd_244.5.bb    |   1 +
 2 files changed, 157 insertions(+)
 create mode 100644 meta/recipes-core/systemd/systemd/0001-udevadm-trigger-implement-initialized-match-nomatch-arguments.patch

diff --git a/meta/recipes-core/systemd/systemd/0001-udevadm-trigger-implement-initialized-match-nomatch-arguments.patch b/meta/recipes-core/systemd/systemd/0001-udevadm-trigger-implement-initialized-match-nomatch-arguments.patch
new file mode 100644
index 0000000000..2f7da0aff9
--- /dev/null
+++ b/meta/recipes-core/systemd/systemd/0001-udevadm-trigger-implement-initialized-match-nomatch-arguments.patch
@@ -0,0 +1,156 @@
+From 678f2b16676cd566c50bdec78350f732a9a3ee41 Mon Sep 17 00:00:00 2001
+From: Danilo Krummrich <danilo.krummrich@bmw.de>
+Date: Mon, 14 Jun 2021 17:46:00 +0200
+Subject: [PATCH] udevadm: trigger: implement --initialized-match/nomatch
+ arguments
+
+systemd-udev-trigger.service by default triggeres all devices regardless
+of whether they were already recognized by systemd-udevd.
+
+There are machines (especially in embedded environments) where
+systemd-udev-trigger.service is configured to run at a later stage of
+the boot sequence, which can lead to quite a lot of devices being
+triggered although they were already recognized by systemd-udevd.
+
+Re-triggering a lot of devices is a relatively expensive operation and
+therefore should be avoided if unnecessary.
+
+Therefore this patch introduces --initialized-nomatch, which filters out
+devices that are already present in the udev database. For consistance
+reasons --initialized-match is implemented as well, which filters out devices
+that are *not* already present in the udev database.
+
+Replaces #19949.
+
+Upstream-Status: Backport [https://github.com/systemd/systemd/commit/678f2b16676cd566c50bdec78350f732a9a3ee41.patch]
+Comment: Refreshed hunk from udevadm, _udevadm and udevadm-trigger.c
+Signed-off-by: Pawan Badganchi <pawan.badganchi@kpit.com>
+---
+ man/udevadm.xml               | 29 +++++++++++++++++++++++++++++
+ shell-completion/bash/udevadm |  3 ++-
+ shell-completion/zsh/_udevadm |  2 ++
+ src/udev/udevadm-trigger.c    | 13 +++++++++++++
+ 4 files changed, 46 insertions(+), 1 deletion(-)
+
+diff --git a/man/udevadm.xml b/man/udevadm.xml
+index 24ed4a29c71d..af485711222e 100644
+--- a/man/udevadm.xml
++++ b/man/udevadm.xml
+@@ -395,6 +395,35 @@
+             then each matching result is ORed, that is, all children of each specified device are triggered.</para>
+           </listitem>
+         </varlistentry>
++        <varlistentry>
++          <term><option>--initialized-match</option></term>
++          <term><option>--initialized-nomatch</option></term>
++          <listitem>
++            <para>When <option>--initialized-match</option> is specified, trigger events for devices
++            that are already initialized by <command>systemd-udevd</command>, and skip devices that
++            are not initialized yet.</para>
++            <para>When <option>--initialized-nomatch</option> is specified, trigger events for devices
++            that are not initialized by <command>systemd-udevd</command> yet, and skip devices that
++            are already initialized.</para>
++            <para>Here, initialized devices are those for which at least one udev rule already
++            completed execution – for any action but <literal>remove</literal> — that set a property
++            or other device setting (and thus has an entry in the udev device database). Devices are
++            no longer considered initialized if a <literal>remove</literal> action is seen for them
++            (which removes their entry in the udev device database). Note that devices that have no
++            udev rules are never considered initialized, but might still be announced via the sd-device
++            API (or similar). Typically, it is thus essential that applications which intend to use
++            such a match, make sure a suitable udev rule is installed that sets at least one property
++            on devices that shall be matched.</para>
++            <para>WARNING: <option>--initialized-nomatch</option> can potentially save a significant
++            amount of time compared to re-triggering all devices in the system and e.g. can be used to
++            optimize boot time. However, this is not safe to be used in a boot sequence in general.
++            Especially, when udev rules for a device depend on its parent devices (e.g.
++            <literal>ATTRS</literal> or <literal>IMPORT{parent}</literal> keys, see
++            <citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
++            for more details), the final state of the device becomes easily unstable with this option.
++            </para>
++          </listitem>
++        </varlistentry>
+         <varlistentry>
+           <term><option>-w</option></term>
+           <term><option>--settle</option></term>
+diff --git a/shell-completion/bash/udevadm b/shell-completion/bash/udevadm
+index 4d52597cbfdf..23ce02365c7f 100644
+--- a/shell-completion/bash/udevadm
++++ b/shell-completion/bash/udevadm
+@@ -51,7 +51,8 @@
+         [INFO_STANDALONE]='-r --root -a --attribute-walk -x --export -e --export-db -c --cleanup-db
+                            -w --wait-for-initialization'
+         [INFO_ARG]='-q --query -p --path -n --name -P --export-prefix -d --device-id-of-file'
+-        [TRIGGER_STANDALONE]='-v --verbose -n --dry-run -w --settle --wait-daemon'
++        [TRIGGER_STANDALONE]='-v --verbose -n --dry-run -w --settle --wait-daemon
++                              --initialized-match --initialized-nomatch'
+         [TRIGGER_ARG]='-t --type -c --action -s --subsystem-match -S --subsystem-nomatch
+                        -a --attr-match -A --attr-nomatch -p --property-match
+                        -g --tag-match -y --sysname-match --name-match -b --parent-match'
+diff --git a/shell-completion/zsh/_udevadm b/shell-completion/zsh/_udevadm
+index 8a10237e3d66..63df8b7c9ecc 100644
+--- a/shell-completion/zsh/_udevadm
++++ b/shell-completion/zsh/_udevadm
+@@ -30,7 +30,9 @@
+         '--property-match=[Trigger events for devices with a matching property value.]' \
+         '--tag-match=property[Trigger events for devices with a matching tag.]' \
+         '--sysname-match=[Trigger events for devices with a matching sys device name.]' \
+-        '--parent-match=[Trigger events for all children of a given device.]'
++        '--parent-match=[Trigger events for all children of a given device.]' \
++        '--initialized-match[Trigger events for devices that are already initialized.]' \
++        '--initialized-nomatch[Trigger events for devices that are not initialized yet.]'
+ }
+ 
+ (( $+functions[_udevadm_settle] )) ||
+diff --git a/src/udev/udevadm-trigger.c b/src/udev/udevadm-trigger.c
+index e4b3150e6039..56921e2cc62e 100644
+--- a/src/udev/udevadm-trigger.c
++++ b/src/udev/udevadm-trigger.c
+@@ -10,6 +10,7 @@
+ #include "device-private.h"
+ #include "fd-util.h"
+ #include "fileio.h"
++#include "parse-util.h"
+ #include "path-util.h"
+ #include "process-util.h"
+ #include "set.h"
+@@ -130,6 +131,8 @@
+                "  -y --sysname-match=NAME           Trigger devices with this /sys path\n"
+                "     --name-match=NAME              Trigger devices with this /dev name\n"
+                "  -b --parent-match=NAME            Trigger devices with that parent device\n"
++               "     --initialized-match            Trigger devices that are already initialized\n"
++               "     --initialized-nomatch          Trigger devices that are not initialized yet\n"
+                "  -w --settle                       Wait for the triggered events to complete\n"
+                "     --wait-daemon[=SECONDS]        Wait for udevd daemon to be initialized\n"
+                "                                    before triggering uevents\n"
+@@ -142,6 +145,8 @@
+         enum {
+                 ARG_NAME = 0x100,
+                 ARG_PING,
++                ARG_INITIALIZED_MATCH,
++                ARG_INITIALIZED_NOMATCH,
+         };
+ 
+         static const struct option options[] = {
+@@ -158,6 +163,8 @@
+                 { "sysname-match",     required_argument, NULL, 'y'      },
+                 { "name-match",        required_argument, NULL, ARG_NAME },
+                 { "parent-match",      required_argument, NULL, 'b'      },
++                { "initialized-match",     no_argument,       NULL, ARG_INITIALIZED_MATCH     },
++                { "initialized-nomatch",   no_argument,       NULL, ARG_INITIALIZED_NOMATCH   },
+                 { "settle",            no_argument,       NULL, 'w'      },
+                 { "wait-daemon",       optional_argument, NULL, ARG_PING },
+                 { "version",           no_argument,       NULL, 'V'      },
+@@ -301,7 +308,12 @@
+                         }
+                         break;
+                 }
+-
++                case ARG_INITIALIZED_MATCH:
++                case ARG_INITIALIZED_NOMATCH:
++                        r = device_enumerator_add_match_is_initialized(e, c == ARG_INITIALIZED_MATCH ? MATCH_INITIALIZED_YES : MATCH_INITIALIZED_NO);
++                        if (r < 0)
++                                return log_error_errno(r, "Failed to set initialized filter: %m");
++                        break;
+                 case 'V':
+                         return print_version();
+                 case 'h':
diff --git a/meta/recipes-core/systemd/systemd_244.5.bb b/meta/recipes-core/systemd/systemd_244.5.bb
index bd66d82932..a398043308 100644
--- a/meta/recipes-core/systemd/systemd_244.5.bb
+++ b/meta/recipes-core/systemd/systemd_244.5.bb
@@ -39,6 +39,7 @@ SRC_URI += "file://touchscreen.rules \
            file://CVE-2023-26604-2.patch \
            file://CVE-2023-26604-3.patch \
            file://CVE-2023-26604-4.patch \
+           file://0001-udevadm-trigger-implement-initialized-match-nomatch-arguments.patch \
            "
 
 # patches needed by musl
-- 
2.38.1