Re: Memory size and section boundary on armv7

[Ilias Apalodimas <ilias.apalodimas@linaro.org>]

> > Can we at least we can print a warning saying "What you are trying to do is not
> > good enough, please re-check the mappings" or something like that, 
> > to help people avoid that in the future.
> > The BUG_ON is supposed to do that, but for some reason i can't see it on my
> > console, any ideas why?
> 
> That may be a possibility, we would have to ignore the request to setup
> the mapping, which means we could end silently locking up shortly
> there-after.
> 
> It may also be possible to slightly rearrange the code to map the
> vectors page before we setup any of the memory mappings (so that
> exceptions can work), but that may need careful handling.
> 
Ok, i'll try to have a look at that, since i can easily reproduce the splat

> > Yes. U-Boot wise we could fix that, by placing the dtb on a non section
> > aligned boundary
> 
> That's actually misleading.
> 
> The problem happens when you have a small no-map section within a 2MB
> region, and it doesn't cross the even-odd 1MB boundary.
> 
> To illustrate what I'm saying, if you arranged for it to be (eg) one
> page higher (iow, 0xc7f01000) then you'll hit the same problem.
Yes correct, i actually tried that as well in one of my tests and still had the
same effect

> > 
> > The easiest way out of it is to place the fdt on !SECTION_SIZE right?
Yes noted, 

Thanks
/Ilias

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel