On Wednesday 09 January 2013, Russell King - ARM Linux wrote: > d = debugfs_create_dir("pm_debug", NULL); > if (IS_ERR_OR_NULL(d)) > return PTR_ERR(d); > > Well, covered above. NULL is success here. This one is actually worse, because in case of debugfs_create_dir, a negative error code is documented to mean "success": The debugfs functions intentionally return ERR_PTR(-ENODEV) when debugfs is disabled so that any code checking for NULL pretends it is a valid pointer, but that code is only allowed to pass this pointer into other debugfs functions that are also stubbed out and never dereference it. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html