The CPU15 erratum on MPC8xx chips can cause incorrect code execution
under certain circumstances, where there is a conditional or indirect
branch in the last word of a page, with a target in the last cache
line
of the next page. This patch implements one of the suggested
workarounds, by forcing a TLB miss whenever execution crosses a page
boundary. This is done by invalidating the pages before and after the
one being loaded into the TLB in the ITLB miss handler.
So you never found a bug workaround without the terrible
overhead of this one? A shame :-(
Segher