On Sun Mar 24, 2024 at 1:29 AM EET, Jarkko Sakkinen wrote: > Tracing with kprobes while running a monolithic kernel is currently > impossible due the kernel module allocator dependency. > > Address the issue by allowing architectures to implement module_alloc() > and module_memfree() independent of the module subsystem. An arch tree > can signal this by setting HAVE_KPROBES_ALLOC in its Kconfig file. > > Realize the feature on RISC-V by separating allocator to module_alloc.c > and implementing module_memfree(). > > Link: https://www.sochub.fi # for power on testing new SoC's with a minimal > stack > Link: > https://lore.kernel.org/all/20220608000014.3054333-1-jar...@profian.com/ # > continuation > Signed-off-by: Jarkko Sakkinen <jar...@kernel.org>
As for testing I tried the kprobes example for boottime tracing dcoumentation: https://www.kernel.org/doc/html/v5.7/trace/boottime-trace.html I.e. ftrace.event { kprobes.vfs_read { probes = "vfs_read $arg1 $arg2" filter = "common_pid < 100" enable } } kernel { console = hvc0 earlycon = sbi trace_options = sym-addr trace_event = "initcall:*" tp_printk dump_on_oops = 2 trace_buf_size = 1M } BR, Jarkko
