> On Mar 21, 2019, at 3:21 AM, Baoquan He <bhe@xxxxxxxxxx> wrote: It appears as is so often the case that the usage has far outpaced the documentation and -EEXIST may be the proper code to return. The correct answer here may be to modify the documentation to note the additional semantic, though if the usage is solely within the kernel it may be sufficient to explain its use in the header comment for the routine (in this case sparse_add_one_section()).