On Tue, 2015-04-21 at 14:50 -0700, Luis R. Rodriguez wrote:

This:
> +	/* MTRR was used if this is non-zero */
> +	if (!dd->wc_cookie)
>  		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);

And this:
> +		dd->wc_cookie = arch_phys_wc_add(pioaddr, piolen);
> +		if (dd->wc_cookie < 0)
> +			ret = -EINVAL;

don't agree on what wc_cookie will be on error.

-- 
Doug Ledford <dledford@redhat.com>
              GPG KeyID: 0E572FDD