cpacf_kma(9)

📦 version 7.3.1, in nixpkgs unstable

💅 cpacf_kma(9) — KMA instruction, but make it make sense 💅

Okay bestie, welcome to the Kernel API Manual entry for cpacf_kma — no cap, this is the function that executes the KMA (CIPHER MESSAGE WITH AUTHENTICATION) instruction. It’s giving kernel crypto, and honestly? Iconic. 🫶✨

✨ NAME ✨

cpacf_kma — executes the KMA (CIPHER MESSAGE WITH AUTHENTICATION) instruction. Periodt. 💖

🦋 SYNOPSIS 🦋

void cpacf_kma (unsigned long func , void *param , u8 *dest , const u8
       *src , unsigned long src_len , const u8 *aad , unsigned long aad_len );

Exact signature, copy-paste ready, protected by vibes. ✨

🌸 ARGUMENTS 🌸

Okay these are the little cuties you pass in:

  • func — the function code passed to KMA; see the CPACF_KMA_xxx defines. This is literally the “what are we doing” knob. 👑
  • param — address of the parameter block; see POP for details on each func. Your parameter-block bestie lives here. 🎀
  • dest — address of the destination memory area. This is the destination address, bestie. 💅
  • src — address of the source memory area. This is the source address, fr fr. 🦋
  • src_len — length of the src operand in bytes. Count those bytes, no cap. 🔢
  • aad — address of the additional authenticated data memory area. AAD said “I’m the moment.” 🌟
  • aad_len — length of the aad operand in bytes. Another byte count, another slay. 💖

💀 SEE ALSO 💀

Kernel file ./arch/s390/include/asm/cpacf.h and the whole cpacf friend group:

🌸 Cute sign-off: source/version ./arch/s390/include/asm, date October 2026, page cpacf_kma(9) — mwah, go forth and KMA responsibly 💋✨

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