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@@ -121,7 +121,7 @@ sudo cat /proc/modules
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\end{codebash}
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This can be a long list, and you might prefer to search for something particular.
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-To search for the \emph{fat} module:
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+To search for the \verb|fat| module:
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\begin{codebash}
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sudo lsmod | grep fat
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\end{codebash}
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@@ -181,7 +181,7 @@ sudo apt-get install kmod linux-headers-5.4.0-80-generic
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\section{Examples}
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\label{sec:examples}
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-All the examples from this document are available within the \emph{examples} subdirectory.
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+All the examples from this document are available within the \verb|examples| subdirectory.
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If there are any compile errors then you might have a more recent kernel version or need to install the corresponding kernel header files.
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@@ -514,7 +514,7 @@ How to do this, is the subject of the remainder of this chapter.
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First of all, make sure that a kernel source tree is available, having exactly the same version as your current kernel.
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Then, find the configuration file which was used to compile your precompiled kernel.
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-Usually, this is available in your current \emph{boot} directory, under a name like \verb|config-5.14.x|.
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+Usually, this is available in your current \verb|boot| directory, under a name like \verb|config-5.14.x|.
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You may just want to copy it to your kernel source tree: \sh|cp /boot/config-`uname -r` .config|.
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Let's focus again on the previous error message: a closer look at the version magic strings suggests that, even with two configuration files which are exactly the same, a slight difference in the version magic could be possible, and it is sufficient to prevent insertion of the module into the kernel.
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@@ -1080,7 +1080,7 @@ You can also read the code of \verb|fs/seq_file.c| in the linux kernel.
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\label{sec:sysfs}
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\emph{sysfs} allows you to interact with the running kernel from userspace by reading or setting variables inside of modules.
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This can be useful for debugging purposes, or just as an interface for applications or scripts.
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-You can find sysfs directories and files under the \emph{sys} directory on your system.
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+You can find sysfs directories and files under the \verb|/sys| directory on your system.
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\begin{codebash}
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ls -l /sys
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@@ -1313,7 +1313,7 @@ In the following example two threads are started, but one needs to start before
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\samplec{examples/completions.c}
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-The \emph{machine} structure stores the completion states for the two threads.
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+The \cpp|machine| structure stores the completion states for the two threads.
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At the exit point of each thread the respective completion state is updated, and \cpp|wait_for_completion| is used by the flywheel thread to ensure that it does not begin prematurely.
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So even though \cpp|flywheel_thread| is started first you should notice if you load this module and run \sh|dmesg| that turning the crank always happens first because the flywheel thread waits for it to complete.
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@@ -1567,7 +1567,7 @@ You might need to do this for a short time and that is OK, but if you do not ena
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\section{Where To Go From Here?}
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\label{sec:where_to_go}
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-For people seriously interested in kernel programming, I recommend \href{https://kernelnewbies.org}{kernelnewbies.org} and the \emph{Documentation} subdirectory within the kernel source code which is not always easy to understand but can be a starting point for further investigation.
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+For people seriously interested in kernel programming, I recommend \href{https://kernelnewbies.org}{kernelnewbies.org} and the \verb|Documentation| subdirectory within the kernel source code which is not always easy to understand but can be a starting point for further investigation.
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Also, as Linus Torvalds said, the best way to learn the kernel is to read the source code yourself.
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If you are interested in more examples of short kernel modules then searching on sites such as Github and Gitlab is a good way to start, although there is a lot of duplication of older LKMPG examples which may not compile with newer kernel versions.
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Jim Huang