On Mon, 9 Sep 2024 18:43:22 -0400 Peter Xu <peterx@xxxxxxxxxx> wrote: > > > > Do we need the logic to clear dirty bit in the child as that in > > > > __copy_present_ptes()? (and also for the pmd's case). > > > > > > > > e.g. > > > > if (vma->vm_flags & VM_SHARED) > > > > pud = pud_mkclean(pud); > > > > > > Yeah, good question. I remember I thought about that when initially > > > working on these lines, but I forgot the details, or maybe I simply tried > > > to stick with the current code base, as the dirty bit used to be kept even > > > in the child here. > > > > > > I'd expect there's only performance differences, but still sounds like I'd > > > better leave that to whoever knows the best on the implications, then draft > > > it as a separate patch but only when needed. > > > > Sorry, but this vaguensss simply leaves me with nowhere to go. > > > > I'll drop the series - let's revisit after -rc1 please. > > Andrew, would you please explain why it needs to be dropped? > > I meant in the reply that I think we should leave that as is, and I think > so far nobody in real life should care much on this bit, so I think it's > fine to leave the dirty bit as-is. > > I still think whoever has a better use of the dirty bit and would like to > change the behavior should find the use case and work on top, but only if > necessary. Well. "I'd expect there's only performance differences" means to me "there might be correctness issues, I don't know". Is it or is it not merely a performance thing?
