3 ms·

Anyone have knowledge of whether microcode can be patched on consumer grade Intel CPUs?

bri3d 5mo ago
Yes? It is regularly; both the firmware or the OS can deliver updates depending on configuration. The Raptor Lake CPUs in question have gone through an enormous number of microcode revisions already due to quite famous voltage scaling issues; it's unclear if this errata is fallout from or related to a similar root cause or just another issue with the processor.
altairprime 5mo ago
https://github.com/intel/intel-linux-processor-microcode-data-files https://github.com/intel/intel-linux-processor-microcode-dat... $ echo 1 > /sys/devices/system/cpu/microcode/reload Hot-swappable, even. TIL!
- xxs 5mo ago
  of course, it's hot-swap material, the microcode is 1st deployed by the bios, then the OS can apply changes as well. Just that it's writable by $ (not #) feels awkward.
  - altairprime 5mo ago
    > Of course it’s hot-swap Microcode updates like this didn’t exist when I first learned sysadmin, so I guess I don’t take such things for granted, sorry!
    - deleted 5mo ago
      [deleted]
__patchbit__ 5mo ago
At boot time, the following package provides the latest Intel CPU microcode data files on NetBSD. sysutils/intel-microcode-netbsd dmesg shows cpu 0: ucode 0xf0->0xf6 cpu 1: ucode 0xf0->0xf6
throwaway2037 5mo ago
Why is this downvoted? (At the time of writing, the text is grey, so it has at least a few downvotes.) This is a good question. As others have noted below, yes, and sometimes you can see kernel logging on start-up when the microcode is loaded.
- varispeed 5mo ago
  [flagged]
  - db48x 5mo ago
    It’s not elitism, it’s just self defense. Every forum starts out with high–value high–signal low–noise conversations and gradually decays towards low–signal high–noise conversations as new people are brought in. The new people are, by definition, new. They don’t know much if anything yet so they cannot participate meaningfully in advanced topics. Naturally they ask questions in order to fill in the gaps in their knowledge. It is simply unfortunate that the effect is to increase the amount of noise in the forum as each new member asks the same questions over and over again. This leads to the most knowledgeable members of the forum dropping out, as the quality of the discussion drops below the point where it is worth their time. See also “Eternal September”.
- wtallis 5mo ago
  It's a dumb question, because it's in reply to a comment that already implies the answer, and it's trivial to find an answer online in less time than it takes to post that question and wait for someone to supply an answer. The subject of CPU microcode update mechanisms is an interesting and relevant topic, but such a shallow, low-effort question is not a good way to promote interesting discussion on that topic.

bri3d 5mo ago

Yes? It is regularly; both the firmware or the OS can deliver updates depending on configuration. The Raptor Lake CPUs in question have gone through an enormous number of microcode revisions already due to quite famous voltage scaling issues; it's unclear if this errata is fallout from or related to a similar root cause or just another issue with the processor.

altairprime 5mo ago

https://github.com/intel/intel-linux-processor-microcode-data-files https://github.com/intel/intel-linux-processor-microcode-dat... $ echo 1 > /sys/devices/system/cpu/microcode/reload Hot-swappable, even. TIL!

xxs 5mo ago
of course, it's hot-swap material, the microcode is 1st deployed by the bios, then the OS can apply changes as well. Just that it's writable by $ (not #) feels awkward.
- altairprime 5mo ago
  > Of course it’s hot-swap Microcode updates like this didn’t exist when I first learned sysadmin, so I guess I don’t take such things for granted, sorry!
  - deleted 5mo ago
    [deleted]

__patchbit__ 5mo ago

At boot time, the following package provides the latest Intel CPU microcode data files on NetBSD. sysutils/intel-microcode-netbsd dmesg shows cpu 0: ucode 0xf0->0xf6 cpu 1: ucode 0xf0->0xf6

throwaway2037 5mo ago

Why is this downvoted? (At the time of writing, the text is grey, so it has at least a few downvotes.) This is a good question. As others have noted below, yes, and sometimes you can see kernel logging on start-up when the microcode is loaded.

varispeed 5mo ago
[flagged]
- db48x 5mo ago
  It’s not elitism, it’s just self defense. Every forum starts out with high–value high–signal low–noise conversations and gradually decays towards low–signal high–noise conversations as new people are brought in. The new people are, by definition, new. They don’t know much if anything yet so they cannot participate meaningfully in advanced topics. Naturally they ask questions in order to fill in the gaps in their knowledge. It is simply unfortunate that the effect is to increase the amount of noise in the forum as each new member asks the same questions over and over again. This leads to the most knowledgeable members of the forum dropping out, as the quality of the discussion drops below the point where it is worth their time. See also “Eternal September”.
wtallis 5mo ago
It's a dumb question, because it's in reply to a comment that already implies the answer, and it's trivial to find an answer online in less time than it takes to post that question and wait for someone to supply an answer. The subject of CPU microcode update mechanisms is an interesting and relevant topic, but such a shallow, low-effort question is not a good way to promote interesting discussion on that topic.