Re: [Bug] Kernel BUG in function_graph tracer in linux kernel 6.16.0-rc2+

[Steven Rostedt]

On Tue, 17 Jun 2025 10:58:09 +0000
duchangbin <changbin.du@xxxxxxxxxx> wrote:

> Hello,
> This is a bug report for kernel function_graph tracer when enabling the
> 'funcgraph-args' option. It seems that the registration logic is not quite
> correct, but I haven't conducted an in-depth analysis of the issue yet.
> This problem has already existed since version 6.15 at least.
> 
> The following are the steps to reproduce the issue.
> 1. Enable CONFIG_FUNCTION_GRAPH_TRACER CONFIG_PROBE_EVENTS_BTF_ARGS
> 2. Trace a function using function_graph tracer and enable the 'funcgraph-args' option.
> # echo 1 > /sys/kernel/debug/tracing/options/funcgraph-args

FYI, please start using /sys/kernel/tracing directly. I want to deprecate
/sys/kernel/debug/tracing.

> # perf ftrace -G vfs_read

Thanks for the report, I posted the fix:

  https://lore.kernel.org/linux-trace-kernel/20250617120830.24fbdd62@xxxxxxxxxxxxxxxxxx/T/#u

-- Steve