On Mon, Mar 6, 2023 at 10:01 AM Thomas Zimmermann [off-list ref] wrote:

Assume that the driver does not own the option string or its substrings
and hence duplicate the option string for the video mode. The driver only
parses the option string once as part of module initialization, so use
a static buffer to store the duplicated mode option. Linux automatically
frees the memory upon releasing the module.

So after module_init is finished, mode_option_buf[] no longer exists?

+                       static char mode_option_buf[256];
+                       int ret;
+
+                       ret = snprintf(mode_option_buf, sizeof(mode_option_buf), "%s", opt);
+                       if (WARN(ret < 0, "fsl-diu-fb: ignoring invalid option, ret=%d\n", ret))
+                               continue;
+                       if (WARN(ret >= sizeof(mode_option_buf), "fsl-diu-fb: option too long\n"))
+                               continue;
+                       fb_mode = mode_option_buf;

If so, then I'm not sure that's going to work.  fb_mode is used after
module_init, in install_fb(), which is called by fsl_diu_probe().