dmar, dma_pool, etc

[Tycho Nightingale]

Hi,

> On Apr 29, 2019, at 2:34 PM, Niclas Zeising <zeising at freebsd.org> wrote:
> 
> On 2019-04-29 20:27, Niclas Zeising wrote:
>> On 2019-04-29 18:00, Tycho Nightingale wrote:
>>>> On Apr 29, 2019, at 11:06 AM, Niclas Zeising <zeising at FreeBSD.org> wrote:
>>>> 
>>>> As a side note, I can readily reproduce the hang on a spare laptop, please let me know if I can help in testing or diagnosing in any way.
>>> 
>>> 
>>> If you can readily reproduce the hang, since there are 2 halves that comprised the fix (the DMA pool and non-pool mappings) it would be instructive to try reverting either dmapool.h or dma-mapping.h independently to see if that helps.
>>> 
>> Hi!
>> I will test this and report back.  Thank you!
>> Regards
> 
> Hi!
> Just reverting dmapool.h or dma-mapping.h doesn't work, it won't build. I need to revert more than that.  Can you help me figure out what to revert in either case, or provide a patch?

Thanks for trying.  I managed to setup my HW and reproduce this and I see your point that it doesn’t cleave in half perfectly.

Since I’ve got a (non)-working test case, let me investigate a bit further.

Tycho