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diff --git a/static/freebsd/man4/textdump.4 3.html b/static/freebsd/man4/textdump.4 3.html new file mode 100644 index 00000000..58a452ad --- /dev/null +++ b/static/freebsd/man4/textdump.4 3.html @@ -0,0 +1,149 @@ +<table class="head"> + <tr> + <td class="head-ltitle">TEXTDUMP(4)</td> + <td class="head-vol">Device Drivers Manual</td> + <td class="head-rtitle">TEXTDUMP(4)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">textdump</code> — + <span class="Nd">textdump kernel dumping facility</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp"><code class="Cd">options DDB</code> + <br/> + <code class="Cd">options KDB</code></p> +<p class="Pp"> + <br/> + <code class="Cd">options TEXTDUMP_PREFERRED</code> + <br/> + <code class="Cd">options TEXTDUMP_VERBOSE</code></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The <code class="Nm">textdump</code> facility allows the capture + of kernel debugging information to disk in a human-readable rather than the + machine-readable form normally used with kernel memory dumps and minidumps. + This representation, while less complete in that it does not capture full + kernel state, can provide debugging information in a more compact, portable, + and persistent form than a traditional dump. By combining + <code class="Nm">textdump</code> with other <a class="Xr">ddb(4)</a> + facilities, such as scripting and output capture, detailed bug information + can be captured in a fully automated manner.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="FORMAT"><a class="permalink" href="#FORMAT">FORMAT</a></h1> +<p class="Pp"><code class="Nm">textdump</code> data is stored in a dump + partition in the same style as a regular memory dump, and will be + automatically extracted by <a class="Xr">savecore(8)</a> if present on + boot.</p> +<p class="Pp"><code class="Nm">textdump</code> files are stored in the + <a class="Xr">tar(5)</a> format, and consist of one or more text files, each + storing a particular type of debugging output. The following parts may be + present:</p> +<dl class="Bl-tag"> + <dt><span class="Pa">ddb.txt</span></dt> + <dd>Captured <a class="Xr">ddb(4)</a> output, if the capture facility has been + used. May be disabled by clearing the + <var class="Va">debug.ddb.textdump.do_ddb</var> sysctl.</dd> + <dt><span class="Pa">config.txt</span></dt> + <dd>Kernel configuration, if <code class="Cd">options + INCLUDE_CONFIG_FILE</code> has been compiled into the kernel. May be + disabled by clearing the + <var class="Va">debug.ddb.textdump.do_config</var> sysctl.</dd> + <dt><span class="Pa">msgbuf.txt</span></dt> + <dd>Kernel message buffer, including recent console output if the capture + facility has been used. May be disabled by clearing the + <var class="Va">debug.ddb.textdump.do_msgbuf</var> sysctl.</dd> + <dt><span class="Pa">panic.txt</span></dt> + <dd>Kernel panic string, if the kernel panicked before the dump was generated. + May be disabled by clearing the + <var class="Va">debug.ddb.textdump.do_panic</var> sysctl.</dd> + <dt><span class="Pa">version.txt</span></dt> + <dd>Kernel version string. My be disabled by clearing the + <var class="Va">debug.ddb.textdump.do_version</var> sysctl.</dd> +</dl> +<p class="Pp">Kernel textdumps may be extracted using + <a class="Xr">tar(1)</a>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="CONFIGURATION"><a class="permalink" href="#CONFIGURATION">CONFIGURATION</a></h1> +<p class="Pp">The <code class="Nm">textdump</code> facility is enabled as part + of the kernel debugger using <code class="Cd">options KDB</code> and + <code class="Cd">options DDB</code>. By default, kernel dumps generated on + panic or via explicit requests for a dump will be regular memory dumps; + however, by using the <code class="Ic">textdump set</code> command in + <a class="Xr">ddb(4)</a>, or by setting the + <var class="Va">debug.ddb.textdump.pending</var> sysctl to 1 using + <a class="Xr">sysctl(8)</a>, it is possible to request that the next dump be + a textdump. One may also directly trigger a textdump in + <a class="Xr">ddb(4)</a> by running the command <code class="Ic">textdump + dump</code>.</p> +<p class="Pp">If at the <a class="Xr">ddb(4)</a> command line, the commands + <code class="Ic">textdump set</code>, <code class="Ic">textdump + status</code>, and <code class="Ic">textdump unset</code> may be used to + set, query, and clear the textdump pending flag.</p> +<p class="Pp">As with regular kernel dumps, a dump partition must be + automatically or manually configured using <a class="Xr">dumpon(8)</a>.</p> +<p class="Pp">Additional kernel <a class="Xr">config(8)</a> options:</p> +<dl class="Bl-tag"> + <dt><code class="Cd">TEXTDUMP_PREFERRED</code></dt> + <dd>sets textdumps to be the default manner of doing dumps. This means there + will be no need to <a class="Xr">sysctl(8)</a> or use the + <code class="Ic">textdump set</code> <a class="Xr">ddb(8)</a> + commands.</dd> + <dt><code class="Cd">TEXTDUMP_VERBOSE</code></dt> + <dd>will have the textdump facility be more verbose about each file it is + emitting as well as other diagnostics useful to debug the textdump + facility itself.</dd> +</dl> +</section> +<section class="Sh"> +<h1 class="Sh" id="EXAMPLES"><a class="permalink" href="#EXAMPLES">EXAMPLES</a></h1> +<p class="Pp">In the following example, the script + <var class="Va">kdb.enter.panic</var> will run when the kernel debugger is + entered as a result of a panic, enable output capture, dump several useful + pieces of debugging information, and then invoke panic in order to force a + kernel dump to be written out followed by a reboot:</p> +<div class="Bd Pp Bd-indent Li"> +<pre>script kdb.enter.panic=textdump set; capture on; show allpcpu; bt; + ps; alltrace; show alllocks; textdump dump; reset</pre> +</div> +<p class="Pp">In the following example, the script + <var class="Va">kdb.enter.witness</var> will run when the kernel debugger is + entered as a result of a witness violation, printing lock-related + information for the user:</p> +<div class="Bd Pp Bd-indent Li"> +<pre>script kdb.enter.witness=show locks</pre> +</div> +<p class="Pp">These scripts may also be configured using the + <a class="Xr">ddb(8)</a> utility.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">tar(1)</a>, <a class="Xr">ddb(4)</a>, + <a class="Xr">tar(5)</a>, <a class="Xr">ddb(8)</a>, + <a class="Xr">dumpon(8)</a>, <a class="Xr">savecore(8)</a>, + <a class="Xr">sysctl(8)</a></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">The <code class="Nm">textdump</code> facility first appeared in + <span class="Ux">FreeBSD 7.1</span>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> +<p class="Pp">The <code class="Nm">textdump</code> facility was created by + <span class="An">Robert N. M. Watson</span>.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">October 18, 2019</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |