Russell King wrote: > Has anyone addressed my issue with it that this is wide-open for > abuse by allocating large chunks of memory, and then remapping > them in some way with different attributes, thereby violating the > ARM architecture specification?
I seem to have missed the previous discussion about this issue. Where in the specification (preferably ARMv7) can I find information about this? Is the problem that it is simply forbidden to map an address multiple times with different cache setting and if this is done the hardware might start failing? Or is the problem that having an address mapped cached means that speculative pre-fetch can read it into the cache at any time, possibly causing problems if an un-cached mapping exists? In my opinion option number two can be handled and I've made an attempt at doing that in hwmem (posted on linux-mm a while ago), look in cache_handler.c. Hwmem currently does not use cma but the next version probably will. /Johan Mossberg -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
