user_enter_callable(9)

✨ user_enter_callable(9) ✨ — from the Kernel API Manual

okay so bestie, gather round 🫶 this one is a little cursed, but we're gonna get through it together.

💖 NAME 💖

user_enter_callable — the unfortunate ASM callable version of user_enter() for archs that didn't manage to check the context tracking static key from low level code. 😭💅

✨ SYNOPSIS ✨

the whole signature is literally:

void user_enter_callable (void );

🫶 ARGUMENTS 🫶

• void — no arguments. that's it, nothing to pass in, no little snack for this function 🍓

💅 DESCRIPTION 💅

okay so this function is OBSOLETE — yes, all caps, it's giving not-the-move energy 💀. It should be noinstr, but it unsafely calls local_irq_restore, involving illegal RCU uses through tracing and lockdep. 😬

This is unlikely to be fixed as this function is obsolete. periodt.

the preferred way is to call user_enter_irqoff ✨. It should be the arch entry code responsibility to call into context tracking with IRQs disabled. no cap.

🌈 SEE ALSO 🌈

Kernel file: ./kernel/context_tracking.c. the whole squad:

• ct_nmi_exit(9)
• ct_nmi_enter(9)
• ct_idle_enter(9)
• ct_idle_exit(9)
• ct_irq_enter(9)
• ct_irq_exit(9)
• __ct_user_enter(9)
• __ct_user_exit(9)
• user_exit_callable(9)

okay bye bestie 💖 source/version: ./kernel · date: October 2026 · page: user_enter_callable(9). periodt 🫶