cpu_device_up(9)

🎀 NAME 🎀

cpu_device_up — bring up a cpu device ✨

Welcome to cpu_device_up(9), bestie — this little icon lives in the Kernel API Manual 💅.

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🌸 SYNOPSIS 🌸

int cpu_device_up (struct device *dev );

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🦋 ARGUMENTS 🦋

• dev — pointer to the cpu device to online 👑

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✨ DESCRIPTION ✨

Okay so listen: this function is meant to be used by the device core cpu subsystem only. Periodt. 💅

Other subsystems should use add_cpu instead. No cap. 🫶

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🔥 RETURN 🔥

• 0 on success 🎉
• a negative errno code 😭

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👑 SEE ALSO 👑

• Kernel file ./kernel/cpu.c 📁
• struct cpuhp_cpu_state(9)
• struct cpuhp_step(9)
• cpuhp_invoke_callback(9)
• cpuhp_ap_update_sync_state(9)
• cpuhp_ap_report_dead(9)
• cpuhp_ap_sync_alive(9)
• clear_tasks_mm_cpumask(9)
• cpu_device_down(9)
• notify_cpu_starting(9)
• bringup_hibernate_cpu(9)
• __cpuhp_setup_state_cpuslocked(9)
• __cpuhp_remove_state_cpuslocked(9)

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okay bye bestie 🫶 — source ./kernel, dated October 2026, and this iconic page is cpu_device_up(9) 💖✨