Merge pull request #7629 from poettering/condition-kernel-version

core,udev,networkd: add ConditionKernelVersion=

man/systemd.link.xml

@@ -172,6 +172,17 @@
           for details.</para>
         </listitem>
       </varlistentry>
+        <varlistentry>
+          <term><varname>KernelVersion=</varname></term>
+          <listitem>
+            <para>Checks whether the kernel version (as reported by <command>uname -r</command>) matches a certain
+            expression (or if prefixed with the exclamation mark does not match it). See
+            <literal>ConditionKernelVersion=</literal> in
+            <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
+            details.
+            </para>
+          </listitem>
+        </varlistentry>
       <varlistentry>
         <term><varname>Architecture=</varname></term>
         <listitem>

man/systemd.netdev.xml

@@ -232,6 +232,16 @@
           </para>
         </listitem>
       </varlistentry>
+      <varlistentry>
+        <term><varname>KernelVersion=</varname></term>
+        <listitem>
+          <para>Checks whether the kernel version (as reported by <command>uname -r</command>) matches a certain
+          expression (or if prefixed with the exclamation mark does not match it). See
+          <literal>ConditionKernelVersion=</literal> in
+          <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> for details.
+          </para>
+        </listitem>
+      </varlistentry>
       <varlistentry>
         <term><varname>Architecture=</varname></term>
         <listitem>

man/systemd.network.xml

@@ -193,6 +193,17 @@
             </para>
           </listitem>
         </varlistentry>
+        <varlistentry>
+          <term><varname>KernelVersion=</varname></term>
+          <listitem>
+            <para>Checks whether the kernel version (as reported by <command>uname -r</command>) matches a certain
+            expression (or if prefixed with the exclamation mark does not match it). See
+            <literal>ConditionKernelVersion=</literal> in
+            <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
+            details.
+            </para>
+          </listitem>
+        </varlistentry>
         <varlistentry>
           <term><varname>Architecture=</varname></term>
           <listitem>

man/systemd.unit.xml

@@ -923,6 +923,7 @@
         <term><varname>ConditionVirtualization=</varname></term>
         <term><varname>ConditionHost=</varname></term>
         <term><varname>ConditionKernelCommandLine=</varname></term>
+        <term><varname>ConditionKernelVersion=</varname></term>
         <term><varname>ConditionSecurity=</varname></term>
         <term><varname>ConditionCapability=</varname></term>
         <term><varname>ConditionACPower=</varname></term>
@@ -1050,6 +1051,17 @@
         the exact assignment is looked for with right and left hand
         side matching.</para>
 
+        <para><varname>ConditionKernelVersion=</varname> may be used to check whether the kernel version (as reported
+        by <command>uname -r</command>) matches a certain expression (or if prefixed with the exclamation mark does not
+        match it). The argument must be a single string. If the string starts with one of <literal>&lt;</literal>,
+        <literal>&lt;=</literal>, <literal>=</literal>, <literal>&gt;=</literal>, <literal>&gt;</literal> a relative
+        version comparison is done, otherwise the specified string is matched with shell-style globs.</para>
+
+        <para>Note that using the kernel version string is an unreliable way to determine which features are supported
+        by a kernel, because of the widespread practice of backporting drivers, features, and fixes from newer upstream
+        kernels into older versions provided by distributions. Hence, this check is inherently unportable and should
+        not be used for units which may be used on different distributions.</para>
+
         <para><varname>ConditionSecurity=</varname> may be used to
         check whether the given security module is enabled on the
         system. Currently, the recognized values are
@@ -1201,6 +1213,7 @@
         <term><varname>AssertVirtualization=</varname></term>
         <term><varname>AssertHost=</varname></term>
         <term><varname>AssertKernelCommandLine=</varname></term>
+        <term><varname>AssertKernelVersion=</varname></term>
         <term><varname>AssertSecurity=</varname></term>
         <term><varname>AssertCapability=</varname></term>
         <term><varname>AssertACPower=</varname></term>