CONFIG_HAVE_CONTEXT_TRACKING_USER (not configurable)
configname: CONFIG_HAVE_CONTEXT_TRACKING_USER
Linux Kernel Configuration
└─>General architecture-dependent options
└─>HAVE_CONTEXT_TRACKING_USER
In linux kernel since version 6 (release Date: 2022-10-02)
Provide kernel/user boundaries probes necessary for subsystems
that need it, such as userspace RCU extended quiescent state.
Syscalls need to be wrapped inside user_exit()-user_enter(), either
optimized behind static key or through the slow path using TIF_NOHZ
flag. Exceptions handlers must be wrapped as well. Irqs are already
protected inside ct_irq_enter/ct_irq_exit() but preemption or signal
handling on irq exit still need to be protected.
that need it, such as userspace RCU extended quiescent state.
Syscalls need to be wrapped inside user_exit()-user_enter(), either
optimized behind static key or through the slow path using TIF_NOHZ
flag. Exceptions handlers must be wrapped as well. Irqs are already
protected inside ct_irq_enter/ct_irq_exit() but preemption or signal
handling on irq exit still need to be protected.