On Fri, Sep 11, 2026 at 10:25:12PM +0800, Leon Hwang wrote:
> tmp_ops.func_hash->filter_hash is annotated __rcu, but
> update_ftrace_direct_mod() assigns hash to it directly. Sparse reports an
> address-space mismatch.
>
> Use rcu_assign_pointer() for the assignment.
>
> Fixes: 50b35c9e50a8 ("ftrace: Use hash argument for tmp_ops in
> update_ftrace_direct_mod")
> Reported-by: kernel test robot <[email protected]>
> Closes:
> https://lore.kernel.org/oe-kbuild-all/[email protected]/
> Signed-off-by: Leon Hwang <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
thanks,
jirka
> ---
> kernel/trace/ftrace.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index 53d5db60bfa5..673a54fdf392 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -6675,7 +6675,7 @@ int update_ftrace_direct_mod(struct ftrace_ops *ops,
> struct ftrace_hash *hash, b
>
> /* Enable the tmp_ops to have the same functions as the hash object. */
> ftrace_ops_init(&tmp_ops);
> - tmp_ops.func_hash->filter_hash = hash;
> + rcu_assign_pointer(tmp_ops.func_hash->filter_hash, hash);
>
> err = register_ftrace_function_nolock(&tmp_ops);
> if (err)
> --
> 2.55.0
>
