[ofa-general] Re: [PATCH 14 of 33] IB/ipath - fix port sharing on powerpc

[Roland Dreier]

I applied this, but I still think there's some more work to do in this
area:

 > The port sharing feature mixed kernel virtual addresses as well as
 > physical addresses for the offset used to describe the mmap address to map
 > the InfiniPath hardware into user space.  This had a conflict on powerpc.
 > The new scheme converts it to a physical address so it doesn't conflict
 > with chip addresses and yet still fits in 40/44 bits so it isn't truncated
 > by 32-bit applications calling mmap64().

there's no guarantee that a physical address fits in 40 or 44 or 63
bits on a 64 bit platform.  So you've fixed this problem on the
platforms you test for now, but it could easily crop up again...