switch mmu context when jump into kernel

powerpc 4xx use mmu context(called TID(0~255)) when translate virtual addr to physical addr. a SPR named PID hold this context, so i think once i enable the addr translate, i have to set PID to current->mm->context
to make translating work correctly. and it should be set to 0 when interrupt or system call arise.
but after studying the kernel source i downloaded from tivo for a long time, i don't find any code to do that job. i think it mostly should be in these place: transfer_to_handler and int_return but it not. is the kernel missing something?

i am sorry if i post this message twice, my netscape got some problem.

Wang

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