From: Casey Leedom <leedom-ut6Up61K2wZBDgjK7y7TUQ@public.gmane.org>
Subject: Re: DMA error when sg->offset value is greater than PAGE_SIZE in
	Intel IOMMU
Date: Mon, 25 Sep 2017 20:05:45 +0000
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| From: Dan Williams <dan.j.williams-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
| Sent: Monday, September 25, 2017 12:31 PM
| ...
| IIUC it looks like this has been broken ever since commit e1605495c716
| "intel-iommu: Introduce domain_sg_mapping() to speed up
| intel_map_sg()". I.e. it looks like the calculation for pte_val should
| be:
| =

|  =A0=A0 pteval =3D (page_to_phys(sg_page(sg)) + sg->offset) | prot;

Hhmmm, shouldn't that be:

    pteval =3D (page_to_phys(sg_page(sg)) + (sg->offset>>PAGE_SHIFT)) | pro=
t;

???

Casey