install-file: make fs_make_very_read_only() static

[thirdparty/systemd.git] / docs / DISTRO_PORTING.md

diff --git a/docs/DISTRO_PORTING.md b/docs/DISTRO_PORTING.md
index 0099a1334aed6473231a5abf087f1a173aa03374..cb230937f4472b31ff760b4b94821f2eeafd1d65 100644 (file)
--- a/docs/DISTRO_PORTING.md
+++ b/docs/DISTRO_PORTING.md
@@ -1,21 +1,21 @@
 ---
 title: Porting systemd To New Distributions
+category: Concepts
+layout: default
+SPDX-License-Identifier: LGPL-2.1-or-later
 ---
 
 # Porting systemd To New Distributions
 
 ## HOWTO
 
-You need to make the follow changes to adapt systemd to your
-distribution:
+You need to make the follow changes to adapt systemd to your distribution:
 
 1. Find the right configure parameters for:
 
-   * `-Drootprefix=`
    * `-Dsysvinit-path=`
    * `-Dsysvrcnd-path=`
    * `-Drc-local=`
-   * `-Dhalt-local=`
    * `-Dloadkeys-path=`
    * `-Dsetfont-path=`
    * `-Dtty-gid=`
@@ -26,11 +26,24 @@ distribution:
 2. Try it out.
 
    Play around (as an ordinary user) with
-   `/usr/lib/systemd/systemd --test --system` for a test run
-   of systemd without booting. This will read the unit files and
-   print the initial transaction it would execute during boot-up.
+   `/usr/lib/systemd/systemd --test --system` for a test run of systemd without booting.
+   This will read the unit files and print the initial transaction it would execute during boot-up.
    This will also inform you about ordering loops and suchlike.
 
+## Compilation options
+
+The default configuration does not enable any optimization or hardening options.
+This is suitable for development and testing, but not for end-user
+installations.
+
+For deployment, optimization (`-O2` or `-O3` compiler options), link time
+optimization (`-Db_lto=true` meson option), and hardening (e.g.
+`-D_FORTIFY_SOURCE=2`, `-fstack-protector-strong`, `-fstack-clash-protection`,
+`-fcf-protection`, `-pie` compiler options, and `-z relro`, `-z now`,
+`--as-needed` linker options) are recommended.
+The most appropriate set of options depends on the architecture and distribution specifics so no default is
+provided.
+
 ## NTP Pool
 
 By default, systemd-timesyncd uses the Google Public NTP servers
@@ -41,8 +54,9 @@ and can be up to .5s off from servers that use stepped leap seconds.
 
 If you prefer to use leap second steps, please register your own
 vendor pool at ntp.org and make it the built-in default by
-passing `-Dntp-servers=` to meson. Registering vendor
-pools is [free](http://www.pool.ntp.org/en/vendors.html).
+passing `-Dntp-servers=` to meson.
+Registering vendor pools is
+[free](http://www.pool.ntp.org/en/vendors.html).
 
 Use `-Dntp-servers=` to direct systemd-timesyncd to different fallback
 NTP servers.
@@ -60,8 +74,8 @@ DNS servers.
 
 The default PAM config shipped by systemd is really bare bones.
 It does not include many modules your distro might want to enable
-to provide a more seamless experience. For example, limits set in
-`/etc/security/limits.conf` will not be read unless you load `pam_limits`.
+to provide a more seamless experience.
+For example, limits set in `/etc/security/limits.conf` will not be read unless you load `pam_limits`.
 Make sure you add modules your distro expects from user services.
 
 Pass `-Dpamconfdir=no` to meson to avoid installing this file and
@@ -69,11 +83,10 @@ instead install your own.
 
 ## Contributing Upstream
 
-We generally do no longer accept distribution-specific patches to
-systemd upstream. If you have to make changes to systemd's source code
-to make it work on your distribution, unless your code is generic
-enough to be generally useful, we are unlikely to merge it. Please
-always consider adopting the upstream defaults. If that is not
-possible, please maintain the relevant patches downstream.
+We generally no longer accept distribution-specific patches to
+systemd upstream.
+If you have to make changes to systemd's source code to make it work on your distribution, unless your code is generic enough to be generally useful, we are unlikely to merge it.
+Please always consider adopting the upstream defaults.
+If that is not possible, please maintain the relevant patches downstream.
 
 Thank you for understanding.