On Fri, Apr 07, 2017 at 12:51:15PM +0200, Mathias Krause wrote: > Why that? It allows fast and CPU local modifications of r/o memory. > OTOH, an approach that needs to fiddle with page table entries > requires global synchronization to keep the individual TLB states in > sync. Hmm.. Not that fast, I'd say.
The fixmaps used for kmap_atomic are per-cpu, no global sync required.