On Sat, Nov 07, 2015 at 11:13:03PM +0100, Gilles Chanteperdrix wrote:
> Well, mapping the same piece of RAM with cacheable and non-cacheable
> mappings on ARM is "undefined behaviour" territory. If you want to
> map some RAM with H_NONCACHED, you should reserve it with something
> like the CMA allocator so that the kernel does not map it in any
> other way. That is one possible reason.
> 
> H_NONCACHED is routinely used on armv4/armv5 (actually, I mixed
> H_DMA with H_NONCACHED, Xenomai core never sets H_DMA, it sets
> H_NONCACHED for shared user/kernel mappings for armv4/armv5, because
> this is required with these architectures). So, it works. However,
> that maybe an issue with LPAE, that would be a second possible reason.

Sounds plausible.  Well I am not going to worry about it, since after
removing the unneeded flags (all of them), things work great.

-- 
Len Sorensen

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