On Wed, Aug 08, 2001 at 12:05:25PM +0100, Nikita Schmidt wrote: > I always thought that the self-mapping entry was used by PALcode to > quickly handle TLB misses. When the appropriate entries of page table > self-mapping are not cached in DTBs, PALcode has to descend through page > tables. I don't remember what happens if the self-mapping is not provided > at all - if things are still working, it means that PALcode has to go the > "slow" way for every TLB miss.
Yes, I guessed it was used by the palcode for the tlb handling (this is why I didn't dropped those lines yet). I had a look and it's not clear why 2.2 segfaults and 2.4 doesn't, actually they seem to initialize the last entry of the pgd the same way... Andrea
