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@@ -1,7 +1,10 @@
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# Signing a custom kernel for Secure Boot
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-(Instructions are for ubuntu, but should work similar for other distros, if they are using shim
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-and grub as bootloader.)
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+Instructions are for ubuntu, but should work similar for other distros, if they are using shim
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+and grub as bootloader. If your distro is not using shim (e.g. Linux Foundation Preloader), there
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+should be similar steps to complete the signing (e.g. HashTool instead of MokUtil for LF Preloader)
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+or you can install shim to use instead. The ubuntu package for shim is called `shim-signed`, but
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+please inform yourself on how to install it correctly, so you do not mess up your bootloader.
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Since the most recent GRUB2 update (2.02+dfsg1-5ubuntu1) in Ubuntu, GRUB2 does not load unsigned
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kernels anymore, as long as Secure Boot is enabled. Users of Ubuntu 18.04 will be notified during
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@@ -13,9 +16,11 @@ Thus you have three options to solve this problem:
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2. You use a signed, generic kernel of your distro.
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3. You disable Secure Boot.
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-Since option two and three are not really viable, these are the steps to sign the kernel yourself:
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+Since option two and three are not really viable, these are the steps to sign the kernel yourself.
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Instructions adapted from [the Ubuntu Blog](https://blog.ubuntu.com/2017/08/11/how-to-sign-things-for-secure-boot).
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+Before following, please backup your /boot/EFI directory, so you can restore everything. Follow
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+these steps on your own risk.
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1. Create the config to create the signing key, save as mokconfig.cnf:
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```
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