On Fri, 3 Jul 2020 08:53:54 -0700 trix@xxxxxxxxxx wrote:
> From: Tom Rix <trix@xxxxxxxxxx>
>
> clang static analysis reports a garbage return
>
> In file included from mm/memory.c:84:
> mm/memory.c:1612:2: warning: Undefined or garbage value returned to caller [core.uninitialized.UndefReturn]
> return err;
> ^~~~~~~~~~
>
> The setting of err depends on a loop executing.
> So initialize err.
>
> ...
>
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -1601,7 +1601,7 @@ int vm_insert_pages(struct vm_area_struct *vma, unsigned long addr,
> return insert_pages(vma, addr, pages, num, vma->vm_page_prot);
> #else
> unsigned long idx = 0, pgcount = *num;
> - int err;
> + int err = -EINVAL;
>
> for (; idx < pgcount; ++idx) {
> err = vm_insert_page(vma, addr + (PAGE_SIZE * idx), pages[idx]);
If a caller were to ask vm_insert_pages() to insert zero pages, I
suspect we should just return zero and set *num to zero.
