Kernelwide

Kernelwide is an adjective used in computing to describe actions, data, or policies that apply across the entire kernel rather than being limited to a single process, subsystem, or user-space component. It denotes scope that encompasses global kernel state, such as global tracing, memory management, or security policies that affect all kernel operations.

Common uses include kernel-wide tracing and monitoring, where instrumentation attaches to multiple subsystems or all threads. Examples include tracepoints and eBPF programs that operate across the running kernel, or global resource accounting that tracks usage system-wide. Kernelwide features may be implemented in the core kernel or exposed through a central subsystem or interface that modules can hook into.

Kernelwide contrasts with per-process or per-module scope, where instrumentation or behavior is limited to a user process, a specific kernel module, or a particular subsystem. In some kernels, kernelwide policies require coordination to maintain consistency when modules load or unload, or when different subsystems interact with shared resources.

Performance and security considerations are important for kernelwide mechanisms. They can introduce system-wide overhead and, if misused, affect all workloads or compromise stability. Access to kernelwide interfaces is typically restricted to privileged code and subject to strict validation, especially for tracing, resource accounting, or memory management functions.

See also: kernel-space, user-space, tracing, eBPF, global variables, resource accounting.