On 5/1/24 5:10 AM, Jason Gunthorpe wrote:
On Tue, Apr 30, 2024 at 10:10:43PM -0700, Christoph Hellwig wrote:
...
This doesn't make sense. IFF a blind retry is all that is needed it should be done in the core functionality. I fear it's not that easy, though.
So do I. :)
+1 This migration retry weirdness is a GUP issue, it needs to be solved in the mm not exposed to every pin_user_pages caller. If it turns out ZONE_MOVEABLE pages can't actually be reliably moved then it is pretty broken..
OK, I'll work on finding out what is temporarily elevating the refcount and preventing the migration. And see where that leads. thanks, -- John Hubbard NVIDIA
