On Thu, Jan 05, 2017 at 10:34:57AM +0100, Miroslav Benes wrote:

quoted

@@ -740,6 +809,14 @@ int klp_register_patch(struct klp_patch *patch)
 		return -ENODEV;
 
 	/*
+	 * Architectures without reliable stack traces have to set
+	 * patch->immediate because there's currently no way to patch kthreads
+	 * with the consistency model.
+	 */
+	if (!klp_have_reliable_stack() && !patch->immediate)
+		return -ENOSYS;
+

I think an error message (pr_err) would be appropriate here. 

$ insmod patch_1.ko
insmod: ERROR: could not insert module patch_1.ko: Function not implemented

is not helpful much :)

Ok :-)

-- 
Josh