Re: [PATCH 02/13] mm/rmap: update to new mmu_notifier semantic

2017-08-31 Thread Nadav Amit
Andrea Arcangeli wrote: > On Wed, Aug 30, 2017 at 08:47:19PM -0400, Jerome Glisse wrote: >> On Wed, Aug 30, 2017 at 04:25:54PM -0700, Nadav Amit wrote: >>> For both CoW and KSM, the correctness is maintained by calling >>> ptep_clear_flush_notify(). If you defer the

Re: [PATCH 02/13] mm/rmap: update to new mmu_notifier semantic

2017-08-31 Thread Andrea Arcangeli
On Wed, Aug 30, 2017 at 08:47:19PM -0400, Jerome Glisse wrote: > On Wed, Aug 30, 2017 at 04:25:54PM -0700, Nadav Amit wrote: > > For both CoW and KSM, the correctness is maintained by calling > > ptep_clear_flush_notify(). If you defer the secondary MMU invalidation > > (i.e., replacing

Re: [PATCH 02/13] mm/rmap: update to new mmu_notifier semantic

2017-08-30 Thread Jerome Glisse
On Wed, Aug 30, 2017 at 04:25:54PM -0700, Nadav Amit wrote: > [cc’ing IOMMU people, which for some reason are not cc’d] > > Andrea Arcangeli wrote: > > > On Wed, Aug 30, 2017 at 11:00:32AM -0700, Nadav Amit wrote: > >> It is not trivial to flush TLBs (primary or secondary)

Re: [PATCH 02/13] mm/rmap: update to new mmu_notifier semantic

2017-08-30 Thread Nadav Amit
[cc’ing IOMMU people, which for some reason are not cc’d] Andrea Arcangeli wrote: > On Wed, Aug 30, 2017 at 11:00:32AM -0700, Nadav Amit wrote: >> It is not trivial to flush TLBs (primary or secondary) without holding the >> page-table lock, and as we recently encountered