On Wed, 7 Aug 2024 15:48:04 -0400 Peter Xu <peterx@xxxxxxxxxx> wrote: > > Dax supports pud pages for a while, but mprotect on puds was missing since > the start. This series tries to fix that by providing pud handling in > mprotect(). The goal is to add more types of pud mappings like hugetlb or > pfnmaps. This series paves way for it by fixing known pud entries. > > Considering nobody reported this until when I looked at those other types > of pud mappings, I am thinking maybe it doesn't need to be a fix for stable > and this may not need to be backported. I would guess whoever cares about > mprotect() won't care 1G dax puds yet, vice versa. I hope fixing that in > new kernels would be fine, but I'm open to suggestions. Yes, I'm not sure this is a "fix" at all. We're implementing something which previously wasn't there. Perhaps the entire series should be called "mm: implement mprotect() for DAX PUDs"?
