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On Wednesday 01 Feb 2017 00:55:01 Marc Joliet wrote: |
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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 |
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> > 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 |
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> > be set as built in elements. I am not using an initramfs (yet) so I |
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> > wonder 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 |
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> remember where). Dracut takes care of this, e.g., the initramfs on my |
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> laptop contains 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 |
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> put the file in the initramfs is for the microcode to get updated as early |
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> as 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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Thanks Marc, I did read the same in the Wiki, where it also mentioned that |
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with systemd all you need to do is mark the microcode as modules in the kernel |
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and systemd will load them at boot time. I did try (twice) to generate a cpio |
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with the blob, but the initrd wouldn't allow the efi stub to boot for some |
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reason. I will revisit this in the next day or two and see if it can work |
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better this time. |
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-- |
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Regards, |
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Mick |
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