isc_unregister(9)

📦 version 7.3.1, in nixpkgs unstable

💅 isc_unregister — the "okay bestie, I'm done with this one" call

So this page is isc_unregister(9) from the Kernel API Manual — it's literally the buddy-system exit door for I/O interruption subclasses, and we're gonna walk through it together 🫶

✨ NAME ✨

isc_unregister — unregister an I/O interruption subclass. That's it, that's the whole job, and she does it flawlessly 👑

🌸 SYNOPSIS 🌸

void isc_unregister (unsigned int isc );

No return value, no drama, just vibes and a void. Periodt 💅

🎀 ARGUMENTS 🎀

  • isc — the I/O interruption subclass you wanna unregister. That's the one. The main character of this function, honestly ✨

🦋 DESCRIPTION 🦋

Okay so here's what actually goes down. The number of users for isc gets decreased — like, its refcount goes down by one, very demure, very mindful 🙈

And if this is the last user to unregister isc, then the corresponding I/O interruption subclass mask gets disabled. Like when the last person leaves the party and the lights go off 💀✨

💜 NOTE 💜

Bestie. Listen to me. This function must not be called if isc_register hasn't been called before by the driver for isc. No registering first, no unregistering. That's the rule, no cap 😭

🧚 CONTEXT 🧚

This function must not be called in interrupt context. Nope, not the vibe. Take it elsewhere, queen 🌈

🔥 SEE ALSO 🔥

  • Kernel file ./drivers/s390/cio/isc.c — go read the source, iykyk 👀
  • isc_register(9) — the matching set, you literally cannot do one without the other fr fr 💖

And that's the whole page, bestie!! 🍓 This iconic little entry lives in ./drivers/s390/cio, dated October 2026, and it's filed under isc_unregister(9) — mwah, slay, go disable some masks responsibly 🌟👑

📦 where this page comes from