On Fri, Sep 21, 2012 at 04:56:03PM +0100, Cyril Chemparathy wrote:
This patch adds support for 64-bit physical addresses in virt_to_phys()
patching. This does not do real 64-bit add/sub, but instead patches in the
upper 32-bits of the phys_offset directly into the output of virt_to_phys.
So this assumes that for the kernel linear mapping, all the physical
addresses have the same upper 32-bit. That's a good optimisation but I
haven't seen this check when calculating lowmem in sanity_check_meminfo.
Someone may build platform with memory starting at 3GB and going across
the 4GB limit.
--
Catalin