> Ewwwwwwwwwww.... you plan to run this in SMP ? So you actually go byte > by byte changing pieces of instructions non atomically and doing > non-Intel's errata friendly XMC. You are really looking for trouble > there :) Two distinct errors can occur:
In this case it is ok because this only happens when transitioning from 1 CPU to 2 CPUs or vice versa and in both cases the other CPUs are essentially stopped. All the other manipulations currently are single byte. I suppose for your immediate value patches something stronger is needed, but we can worry about that post .23. > What I don't like about this particular implementation is that it does > not support "poking" more than 1 byte. In order to support this, you > would have to deal with the case where the address range spans over more > than one page. I considered it, but the function would have been at least twice as big to handle all the corner cases. And for the current callers it's all fine. > Also, doing the copy in the same interface seems a bit awkward. Splitting it would also seem quite awkward. > > I would much prefer something like: > > void *map_shadow_write(void *addr, size_t len); > (returns a pointer to the shadow writable pages, at the same page offset > as "addr") > > int unmap_shadow_write(void *shadow_addr, size_t len); > (unmap the shadow pages) > > Then, the in-kernel user is free to modify their pages as they like. > Since we cannot foresee each modification pattern, I think that leaving > this kind of flexibility is useful. You could as well call vmap directly then; it's not that much more complicated. I don't really see much value in complicating it right now. -Andi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
