In commit 06aeaaeabf69da4, many ftrace-related config options are consolidated. By accident, I guess, the choice about DYNAMIC_FTRACE and DYNAMIC_FTRACE_WITH_REGS is no longer available explicitly but determined by the sole availability on the architecture. This makes it hard to introduce DYNAMIC_FTRACE_WITH_REGS if it depends on new compiler features or other new properties of the toolchain without breaking existing configurations. This patch turns the def_bool into an actual choice. Should the toolchain not meet the requirements for _WITH_REGS it can be turned off. Signed-off-by: Torsten Duwe <duwe@xxxxxxx> --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -508,9 +508,15 @@ config DYNAMIC_FTRACE otherwise has native performance as long as no tracing is active. config DYNAMIC_FTRACE_WITH_REGS - def_bool y + bool "Include register content tracking in dynamic ftrace facility" + default y depends on DYNAMIC_FTRACE depends on HAVE_DYNAMIC_FTRACE_WITH_REGS + help + This architecture supports the inspection of register contents, + as passed between functions, at the dynamic ftrace points. + This is also a prerequisite for Kernel Live Patching (KLP). + When in doubt, say Y. config FUNCTION_PROFILER bool "Kernel function profiler"
