[PATCH] ftrace: Use rcu_assign_pointer() for tmp_ops filter hash

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 <redacted>
Closes: https://lore.kernel.org/oe-kbuild-all/202609110704.Q3M5vCDV-lkp@intel.com/ (local)
Signed-off-by: Leon Hwang <redacted>
---
 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