"Write both dist bytes as a single 2-byte store. This avoids the `movb %ch, [mem]` instruction pattern (store from high-byte register alias) that LLVM otherwise emits when dist arrives as a wide register. That pattern triggers the Intel Raptor Lake CPU errata, causing silent 2-byte stores that corrupt the adjacent `len` byte."
This is worse than https://en.wikipedia.org/wiki/Pentium_FDIV_bug
https://news.ycombinator.com/item?id=27244941
Edit: you should probably read the article I linked first.
$ echo 1 > /sys/devices/system/cpu/microcode/reload
Just that it's writable by $ (not #) feels awkward.
Microcode updates like this didn’t exist when I first learned sysadmin, so I guess I don’t take such things for granted, sorry!
sysutils/intel-microcode-netbsd
cpu 0: ucode 0xf0->0xf6
cpu 1: ucode 0xf0->0xf6This 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.
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.