Dear Ralf,
commit c17a6554 unintentionally(?) modified the PAGE_MASK type
from (int) to (long unsigned int).
This breaks ioremap (and possibly more) when using 64BIT_PHYS_ADDR on
32 bit systems.
Example of failing code from ioremap.c:
phys_addr &= PAGE_MASK;
Since phys_addr is 64 bit (unsigned long long) when 64BIT_PHYS_ADDR and
PAGE_MASK is 32bit (long unsigned int), the upper 32 bits will always
be zeroed which is not what we want/expect.
The code above works if PAGE_MASK is a _signed_ 32bit int though.
Some possible fixes:
A) Simply revert the commit. Makes ioremap work again, but then PAGE_MASK
is a signed int. Do we really want a mask that is 'signed'?
B) Don't use PAGE_MASK for physical addresses. x86 defines this:
/* Cast PAGE_MASK to a signed type so that it is sign-extended if
virtual addresses are 32-bits but physical addresses are larger
(ie, 32-bit PAE). */
#define PHYSICAL_PAGE_MASK (((signed long)PAGE_MASK) & __PHYSICAL_MASK)
Perhaps mips need something similar?
This is an issue with 3.8 and doesn't seem to be solved in master either.
Regards,
/Thomas
