On Fri, 11 Jul 2014 00:53:26 +0300 Oded Gabbay oded.gabbay@gmail.com wrote:
From: Andrew Lewycky Andrew.Lewycky@amd.com
This patch changes the location of the mmu_notifier_invalidate_page function call inside try_to_unmap_one. The mmu_notifier_invalidate_page function call tells the IOMMU that a pgae should be invalidated.
The location is changed from after releasing the physical page to before releasing the physical page.
This change should prevent the bug that would occur in the (rare) case where the GPU attempts to access a page while the CPU attempts to swap out that page (or discard it if it is not dirty).
um OK, but what is the effect on all the other mmu_notifier_ops.invalidate_page() implementations?
Please spell this out in full detail within the changelog and be sure to cc the affected maintainers.