Hacker News with Generative AI: Microcode

Undocumented 8086 instructions, explained by the microcode (righto.com)
What happens if you give the Intel 8086 processor an instruction that doesn't exist?
Computer Architecture, Assembly Language, Microcode
14 points by birdculture 1 day ago | 3 comments
Notes on the Pentium's microcode circuitry (righto.com)
Most people think of machine instructions as the fundamental steps that a computer performs. However, many processors have another layer of software underneath: microcode. With microcode, instead of building the processor's control circuitry from complex logic gates, the control logic is implemented with code known as microcode, stored in the microcode ROM. To execute a machine instruction, the computer internally executes several simpler micro-instructions, specified by the microcode.
Computer Architecture, Microcode, Hardware, Processors, History
179 points by leotravis10 2 days ago | 32 comments
Zentool – AMD Zen Microcode Manipulation Utility (github.com/google)
This package provides a suite of tools for analyzing, manipulating and generating microcode patches for AMD Zen processors.
AMD Processors, Software, Microcode, Programming, Security
236 points by taviso 28 days ago | 66 comments
Zen and the Art of Microcode Hacking (bughunters.google.com)
Zen, Hacking, Microcode, Software Engineering, Security
68 points by nspaced 28 days ago | 3 comments
The biggest microcode attack in our history is underway (theregister.com)
When your state machines are vulnerable, all bets are off
Security, Cybersecurity, Microcode, Computer Science, State Machines
18 points by LorenDB 51 days ago | 3 comments
The biggest microcode attack in our history is underway (theregister.com)
When your state machines are vulnerable, all bets are off
Cybersecurity, Microcode, Attacks, Hardware Security
18 points by rntn 51 days ago | 2 comments
AMD: Microcode Signature Verification Vulnerability (github.com/google)
Google Security Team has identified a security vulnerability in some AMD Zen-based CPUs. This vulnerability allows an adversary with local administrator privileges (ring 0 from outside a VM) to load malicious microcode patches. We have demonstrated the ability to craft arbitrary malicious microcode patches on Zen 1 through Zen 4 CPUs. The vulnerability is that the CPU uses an insecure hash function in the signature validation for microcode updates.
Security, AMD, CPU, Microcode, Vulnerability
287 points by todsacerdoti 58 days ago | 105 comments
Intel Raptor Lake 0x129 CPU Microcode Performance Impact on Linux (phoronix.com)
Intel Processors, Linux, Performance, Hardware, Microcode
40 points by dangle1 234 days ago | 9 comments
Intel confirms no recall for Raptor Lake CPUs,microcode won't fix affected units (videocardz.com)
Hardware, CPUs, Intel, Microcode
119 points by josephcsible 250 days ago | 72 comments