lib/nmi_backtrace.c

File Facts

System

Linux kernel

Corpus path

lib/nmi_backtrace.c

Extension

.c

Size

3821 bytes

Lines

133

Domain

Kernel Services

Bucket

lib

Inferred role

Kernel Services: implementation source

Status

source implementation candidate

Why This File Exists

Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.

• Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/cpumask.h
• linux/delay.h
• linux/kprobes.h
• linux/stringify.h
• linux/nmi.h
• linux/cpu.h
• linux/sched/debug.h

Detected Declarations

• function raise
• function nmi_cpu_backtrace

Annotated Snippet

if (!READ_ONCE(backtrace_idle) && regs && cpu_in_idle(instruction_pointer(regs))) {
			pr_warn("NMI backtrace for cpu %d skipped: idling at %pS\n",
				cpu, (void *)instruction_pointer(regs));
		} else {
			pr_warn("NMI backtrace for cpu %d\n", cpu);
			if (regs)
				show_regs(regs);
			else
				dump_stack();
		}
		printk_cpu_sync_put_irqrestore(flags);
		cpumask_clear_cpu(cpu, to_cpumask(backtrace_mask));
		return true;
	}

	return false;
}
NOKPROBE_SYMBOL(nmi_cpu_backtrace);
#endif

Annotation

• Immediate include surface: `linux/cpumask.h`, `linux/delay.h`, `linux/kprobes.h`, `linux/stringify.h`, `linux/nmi.h`, `linux/cpu.h`, `linux/sched/debug.h`.
• Detected declarations: `function raise`, `function nmi_cpu_backtrace`.
• Atlas domain: Kernel Services / lib.
• Implementation status: source implementation candidate.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.