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@@ -18,7 +18,7 @@
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<h2 class='titleHead'>The Linux Kernel Module Programming Guide</h2>
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<div class='author'><span class='ecrm-1200'>Peter Jay Salzman, Michael Burian, Ori Pomerantz, Bob Mottram, Jim Huang</span></div><br />
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-<div class='date'><span class='ecrm-1200'>October 21, 2022</span></div>
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+<div class='date'><span class='ecrm-1200'>October 22, 2022</span></div>
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@@ -101,9 +101,9 @@
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<!-- l. 65 --><p class='noindent'>The Linux Kernel Module Programming Guide is a free book; you may reproduce
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and/or modify it under the terms of the <a href='https://opensource.org/licenses/OSL-3.0'>Open Software License</a>, version
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3.0.
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-</p><!-- l. 67 --><p class='indent'> This book is distributed in the hope it will be useful, but without any warranty,
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-without even the implied warranty of merchantability or fitness for a particular
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-purpose.
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+</p><!-- l. 67 --><p class='indent'> This book is distributed in the hope that it would be useful, but without any
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+warranty, without even the implied warranty of merchantability or fitness for a
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+particular purpose.
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</p><!-- l. 69 --><p class='indent'> The author encourages wide distribution of this book for personal or commercial
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use, provided the above copyright notice remains intact and the method adheres to
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the provisions of the <a href='https://opensource.org/licenses/OSL-3.0'>Open Software License</a>. In summary, you may copy and
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@@ -577,13 +577,14 @@ is as simple as this:
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<a id='x1-13076r8'></a><span class='ecrm-0500'>8</span>
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<a id='x1-13078r9'></a><span class='ecrm-0500'>9</span><span class='ectt-0800'>clean:</span>
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<a id='x1-13080r10'></a><span class='ecrm-0500'>10</span><span class='ectt-0800'> make -C /lib/modules/</span><span class='colorbox' id='colorbox69'><span class='ectt-0800'>$</span></span><span class='ectt-0800'>(shell uname -r)/build M=</span><span class='colorbox' id='colorbox70'><span class='ectt-0800'>$</span></span><span class='ectt-0800'>(PWD) clean</span></pre>
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-<!-- l. 443 --><p class='indent'> Now have a look at <a href='https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/drivers/char/Makefile'>drivers/char/Makefile</a> for a real world example. As you can
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-see, some things get hardwired into the kernel (<span class='obeylines-h'><span class='verb'><span class='ectt-1000'>obj-y</span></span></span>) but where are all those <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>obj-m</span></span></span>
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-gone? Those familiar with shell scripts will easily be able to spot them. For those not,
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-the <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>obj-$(CONFIG_FOO)</span></span></span> entries you see everywhere expand into <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>obj-y</span></span></span> or <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>obj-m</span></span></span>,
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-depending on whether the <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>CONFIG_FOO</span></span></span> variable has been set to <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>y</span></span></span> or <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>m</span></span></span>. While we are
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-at it, those were exactly the kind of variables that you have set in the <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>.config</span></span></span> file in
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-the top-level directory of Linux kernel source tree, the last time when you said
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+<!-- l. 443 --><p class='indent'> Now have a look at <a href='https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/drivers/char/Makefile'>drivers/char/Makefile</a> for a real world example. As
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+you can see, some things got hardwired into the kernel (<span class='obeylines-h'><span class='verb'><span class='ectt-1000'>obj-y</span></span></span>) but where
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+have all those <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>obj-m</span></span></span> gone? Those familiar with shell scripts will easily be
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+able to spot them. For those who are not, the <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>obj-$(CONFIG_FOO)</span></span></span> entries
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+you see everywhere expand into <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>obj-y</span></span></span> or <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>obj-m</span></span></span>, depending on whether the
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+<span class='obeylines-h'><span class='verb'><span class='ectt-1000'>CONFIG_FOO</span></span></span> variable has been set to <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>y</span></span></span> or <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>m</span></span></span>. While we are at it, those were
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+exactly the kind of variables that you have set in the <span class='obeylines-h'><span class='verb'><span class='ectt-1000'>.config</span></span></span> file in the
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+top-level directory of Linux kernel source tree, the last time when you said
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<code> <span class='ectt-1000'>make menuconfig</span>
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</code> or something like that.
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</p><!-- l. 449 --><p class='noindent'>
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@@ -601,10 +602,10 @@ when the init function is invoked, this makes perfect sense.
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like <code> <span class='ectt-1000'>__init</span>
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</code>, has no effect for loadable modules. Again, if you consider when the cleanup function
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runs, this makes complete sense; built-in drivers do not need a cleanup function,
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-while loadable modules do.
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+while loadable modules do.
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</p><!-- l. 459 --><p class='indent'> These macros are defined in <a href='https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/include/linux/init.h'>include/linux/init.h</a> and serve to free up kernel
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memory. When you boot your kernel and see something like Freeing unused kernel
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memory: 236k freed, this is precisely what the kernel is freeing.
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jserv