Re: DMA error when sg->offset value is greater than PAGE_SIZE in Intel IOMMU

[Casey Leedom]

| From: Raj, Ashok <ashok.raj@xxxxxxxxx>
| Sent: Monday, September 25, 2017 8:54 AM
|
| Not sure how the page->offset would end up being greater than page-size?
|
| If you have additional traces, please send them by.
|
| Is this a new driver? wondering how we didn't run into this?

  According to Herbert Xu and one of our own engineers, it's actually legal
for Scatter/Gather Lists to have this.  This isn't my area of expertise
though so I'm just passing that on.

  I've asked our team to produce a detailed trace of the exact
Scatter/Gather Lists they're seeing and what ends up coming out of the DMA
Mappings, etc.  They're in India, so I expect that they'll have this for you
by tomorrow morning.

Casey