August 10, 2026
smiiiiii happens
Exploiting System Management Mode with a very long interrupt
A ridiculously long computer move may have cracked a hidden safety layer — and commenters are howling
TLDR: Researchers say a hidden processor safety mode can be broken if one core is trapped in a single absurdly slow action for about a second. Commenters swung between laughing at the article’s dramatic “long instruction” gag and worrying that the obvious fix could be an ugly forever-wait hack.
A security write-up about breaking a hidden chip safety mode somehow turned into the internet’s favorite comedy bit: just make one computer instruction absurdly, painfully, comically long. The core discovery is serious — a researcher says one CPU core can get stuck doing a single task for over a second, while another core slips into a secret high-privilege mode alone, breaking a rule that says they should all enter together. In plain English: a built-in protection system may be fooled if one part of the processor is too busy to answer the door.
But in the comments, readers were almost as obsessed with the presentation as the exploit. One person delighted in the README’s over-the-top “LOOOOOONG instruction” bit, saying the extra-dramatic formatting made the whole thing more entertaining. Another immediately went for the practical hot take: why is there even a 1-second timeout? That sparked the classic fix-it debate, with commenters half-joking that the patch will be to make the wait effectively forever — because nothing says modern computing like solving one nightmare by inventing another.
The most anxious reaction came from people asking the question everyone asks when low-level security gets weird: please tell me this isn’t easy to abuse. Others pointed to a deliciously awkward detail in the code comments: the firmware makers basically say vendors should choose a timeout longer than the longest possible operation, which readers interpreted as a giant flashing “good luck with that” sign. And yes, there was meme fuel too: a commenter with minimal hardware knowledge still came away charmed, ending simply with “smiiiiiiii” — which may now be the unofficial scream of this bug.
Key Points
- •The article says SMM security depends on all CPU cores entering or leaving SMM together.
- •The attack keeps one core outside SMM by making it execute a single instruction that lasts longer than the firmware’s one-second SMM synchronization timeout.
- •The firmware code shown waits for all cores to arrive in SMM or exits the wait loop when the timeout expires.
- •Because SMI delivery occurs at instruction boundaries, the delay must come from one uninterruptible instruction rather than many shorter ones.
- •The proof of concept uses a slow MMIO read with a wide `vmovdqu` load on a Zen 3 Ryzen 7 5800H at address `0xfcc68860` to create the required stall.