Re: [RFC v1 1/3] mm/mmu_notifier: Add a new notifier for mapping updates (new pages)

Jason Gunthorpe
2023-07-24T13:37:43Z

On Mon, Jul 24, 2023 at 11:36:47PM +1000, Alistair Popple wrote:

> My primary issue with this patch is the notifier is called without the
> PTL while providing a PTE value.

Right, this is no-go. The PTE value must be protected by the PTLs at
all times. We've made enough bugs already by being lazy with this in
the past..

And I don't think the existing sequence locking helps make sense of
this at all..

Jason