Physical memory start contraints in the Linux kernel (Was: Re: Xen osstest on Calxeda midway progress (Was: Re: [Xen-devel] [xen-unstable test] 21486: tolerable FAIL - PUSHED))

[Russell King - ARM Linux]

On Tue, Nov 12, 2013 at 04:24:46PM +0100, Michal Simek wrote:
> On 11/12/2013 02:20 PM, Russell King - ARM Linux wrote:
> > diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
> > index f52150d2ec00..1957d54198ad 100644
> > --- a/arch/arm/kernel/setup.c
> > +++ b/arch/arm/kernel/setup.c
> > @@ -660,6 +660,17 @@ int __init arm_add_memory(u64 start, u64 size)
> >  	}
> >  #endif
> >  
> > +	if (aligned_start < PHYS_OFFSET) {
> > +		if (aligned_start + size < PHYS_OFFSET) {
> 
> just a note I sent to Russell. Here should be "<=" instead of just "<"
> 
> > +			pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n",
> > +				aligned_start, aligned_start + size);
> > +			return -EINVAL;
> > +		}
> > +
> > +		size -= PHYS_OFFSET - aligned_start;
> > +		aligned_start = PHYS_OFFSET;
> 
> We should printk a message here to be aware that alignment was done.

Yep, you sent me an updated patch, I haven't added anything to my
kernel tree for about a week and a bit now as I want to get what's
already there into Linus' tree.  Once that stuff has gone, I'll see
about adding some of these fixes we need into the queue.