Re: [Xen-devel] Xen-unstable panic: FATAL PAGE FAULT

[Keir Fraser <keir.fraser@xxxxxxxxxxxxx>]

On 31/08/2010 16:07, "Jan Beulich" <JBeulich@xxxxxxxxxx> wrote:

>>>> On 31.08.10 at 16:49, Keir Fraser <keir.fraser@xxxxxxxxxxxxx> wrote:
>> I'm cc'ing Jan to see what we can get away with in doing arithmetic on
>> page_info pointers. What's the guaranteed smallest aligned contiguous ranges
>> of mfn in the frame_table now, Jan? (i.e., ranges in which adjacent
>> page_info structs relate to adjacent MFNs)
> 
> Any range of struct page_info-s that crosses a 2Mb boundary is
> unsafe to make assumptions upon

Where is even that constraint ensured in the code? I can't see it (I would
have assumed that pfn_pdx_hole_setup() would be ensuring it).

 -- Keir

> (with 32-byte struct page_info
> that means 256Mb of memory, but if struct page_info grows that
> range might shrink). If that limit is too low, we might need to
> enforce a lower limit on the bit positions on which compression
> may be done (possibly at the price of doing less compression).




_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel