[PATCH v2] ARC: Use max_high_pfn as a HIGHMEM zone border

Commit 4af22ded0ecf ("arc: fix memory initialization for systems with two memory banks") fixed highmem, but for the PAE case it causes bug messages: BUG: Bad page state in process swapper pfn:8 page:(ptrval) refcount:0 mapcount:1 mapping: index:0x0 pfn:0x8 flags: 0x0() raw: 00

[PATCH v2] ARC: Use 40-bit physical page mask for PAE

32-bit PAGE_MASK can not be used as a mask for physical addresses when PAE is enabled. PAGE_MASK_PHYS must be used for physical addresses instead of PAGE_MASK. Without this, init gets SIGSEGV if pte_modify was called: potentially unexpected fatal signal 11. Path: /bin/busybox CPU: 0 PID: 1 Comm: