12 Aug
2021
12 Aug
'21
5:01 p.m.
Hi Daniel,
On Thu, Aug 12, 2021 at 03:14:12PM +0200, Daniel Vetter wrote:
Aside from deleting lots of code the real motivation here is to switch the mmap over to VM_PFNMAP, to be more consistent with what real gpu drivers do. They're all VM_PFNMP, which means get_user_pages doesn't work, and even if you try and there's a struct page behind that, touching it and mucking around with its refcount can upset drivers real bad.
The only thing I understood of all this complicated stuff was "deleting lots of code" which is a good thing. You may want to s/VM_PFNMP/VM_PFNMAP/ before you push this.
Sam