On Fri, 8 May 2020 at 07:33, Paolo Bonzini <pbonz...@redhat.com> wrote: > > On 08/05/20 08:24, Philippe Mathieu-Daudé wrote: > > It is not clear if dccvap_writefn() really needs > > memory_region_writeback() or could use memory_region_msync(). > > Indeed, I don't understand the code and why it matters that > mr->dirty_log_mask is nonzero. > > mr->dirty_log_mask tells if dirty tracking has been enabled, not if the > page is dirty. It would always be true during live migration and when > running on TCG, but otherwise it would always be false. > > Beata, can you explain what you had in mind? :) > It has been a while ... , but the intention there was to skip the sync if there is nothing to be synced in the first place - so for performance reasons. I honestly do not recall why I went for the dirty_log_mask, as that seems not to be the right choice .
BR Beata > Paolo >