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On Sunday 29 January 2017 13:51:39 Mick wrote: |
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> Hi All, |
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> |
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> I am trying out a systemd installation on a MackBook Pro and I am not sure |
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> the documentation on systemd + microcode is entirely correct. So, I read |
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> here: |
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> |
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> https://wiki.gentoo.org/wiki/Intel_microcode#systemd |
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> |
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> that the "microcode loader is set as a module in the kernel configuration". |
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> However, my kernel configuration is not offering this option. Both 'CPU |
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> microcode loading support' and 'Intel microcode loading support' can only be |
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> set as built in elements. I am not using an initramfs (yet) so I wonder |
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> how I should go about this. |
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|
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AIUI these days the microcode is supposed to be put in the initramfs and |
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loaded from there during early boot (I read this somewhere, but don't remember |
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where). Dracut takes care of this, e.g., the initramfs on my laptop contains |
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a microcode blob: |
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|
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# lsinitrd /boot/initramfs-4.9.6-gentoo.img|grep -i micro |
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drwxr-xr-x 1 root root 0 Jan 27 01:14 kernel/x86/microcode |
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-rw-r--r-- 1 root root 983040 Jan 27 01:14 |
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kernel/x86/microcode/GenuineIntel.bin |
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|
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The third journal entry on said laptop is then: |
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|
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Jan 30 20:42:17 localhost kernel: microcode: microcode updated early to |
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revision 0x4, date = 2013-06-28 |
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|
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So it looks to me like the kernel loads it autonomously, and the reason to put |
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the file in the initramfs is for the microcode to get updated as early as |
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possible (before the kernel has to read from disk). |
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|
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HTH |
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-- |
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Marc Joliet |
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-- |
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"People who think they know everything really annoy those of us who know we |
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don't" - Bjarne Stroustrup |
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