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(upbeat music)

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- [Instructor] We have some good challenges for you,

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and please, do the challenges.

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That's where you're going to learn the most.

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So let's see.

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We want to configure and build kernels.

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So do a configuration.

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You can use either make menuconfig

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or make xconfig.

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So we want you to remove ReisderFS support,

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and there's a hint that's a file system.

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And then enable debug_atomic_sleep,

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wherever you can find that.

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I'm assuming it's not already enabled.

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And you can read the help

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if you want to learn more about that.

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And then look at the help for disabling heap randomization

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and determine is that safe to disable on recent distros.

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And what does disable mean?

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Setting it to what?

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What's the default for that?

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And then is KVM enabled as a module?

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KVM is the kernel virtual machine.

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That's what's used to make VMs

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for Linux running VMs.

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And in the help for that, you should be able to find out

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what the module will be called.

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And things that need to use KVM,

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we'll use a device file,

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and the help should tell you the path to the device file.

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So see that.

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Then go ahead and build bzImage.

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Where is the resulting bzImage file?

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I think we showed you that.

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How big is it?

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Compare that size to the size

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of the /boot/vmlinuz- kernel version file.

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See if they're vastly different or pretty close to the same.

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And then you should have also had vmLinux built.

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Find that.

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How big is that?

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What kind of file is that?

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All right, those are some good challenges.