Dear Jean, On Thu, Apr 30, 2020 at 8:11 PM Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx> wrote: > > If the SMMU supports it and the kernel was built with HTTU support, enable is there any framework/config for HTTU which must be enabled to use this patch? > We can enable HTTU even if CPUs don't support it, because the kernel > always checks for HW dirty bit and updates the PTE flags atomically. > I believe, this statement is valid in context of this patch-set only. One cannot use code snipped to test HTTU because exiting io-pgtable-arm.c driver doesn't have framework to leverage HTTU benfits. It by-default sets AF=1 and does not set DBM. Thanks --pk