man/systemd-tpm2-generator.xml

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   9 <refentry id="systemd-tpm2-generator">
  10
  11   <refentryinfo>
  12     <title>systemd-tpm2-generator</title>
  13     <productname>systemd</productname>
  14   </refentryinfo>
  15
  16   <refmeta>
  17     <refentrytitle>systemd-tpm2-generator</refentrytitle>
  18     <manvolnum>8</manvolnum>
  19   </refmeta>
  20
  21   <refnamediv>
  22     <refname>systemd-tpm2-generator</refname>
  23     <refpurpose>Generator for inserting TPM2 synchronization point in the boot process</refpurpose>
  24   </refnamediv>
  25
  26   <refsynopsisdiv>
  27     <para><filename>/usr/lib/systemd/system-generators/systemd-tpm2-generator</filename></para>
  28   </refsynopsisdiv>
  29
  30   <refsect1>
  31     <title>Description</title>
  32
  33     <para><command>systemd-tpm2-generator</command> is a generator that adds a <varname>Wants=</varname>
  34     dependency from <filename>sysinit.target</filename> to <filename>tpm2.target</filename> when it detects
  35     that the firmware discovered a TPM2 device but the OS kernel so far did
  36     not. <filename>tpm2.target</filename> is supposed to act as synchronization point for all services that
  37     require TPM2 device access. See
  38     <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry> for
  39     details.</para>
  40
  41     <para>The <option>systemd.tpm2_wait=</option> kernel command line option may be used to override
  42     behaviour of the generator. It accepts a boolean value: if true then <filename>tpm2.target</filename>
  43     will be added as synchronization point even if the firmware has not detected a TPM2 device. If false, the
  44     target will not be inserted even if firmware reported a device but the OS kernel does not expose a device
  45     for it yet. The latter might be useful in environments where a suitable TPM2 driver for the available
  46     hardware is not available.</para>
  47
  48     <para><command>systemd-tpm2-generator</command> implements
  49     <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
  50   </refsect1>
  51
  52   <refsect1>
  53     <title>See Also</title>
  54     <para><simplelist type="inline">
  55       <member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
  56       <member><citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry></member>
  57       <member><citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry></member>
  58     </simplelist></para>
  59   </refsect1>
  60 </refentry>