Re: [PATCH v3 19/20] PCI/P2PDMA: introduce pci_mmap_p2pmem()

[Christian König]

Am 04.10.21 um 15:27 schrieb Jason Gunthorpe:
> On Mon, Oct 04, 2021 at 03:22:22PM +0200, Christian König wrote:
>
> > That use case is completely unrelated to GUP and when this doesn't work we
> > have quite a problem.
> My read is that unmap_mapping_range() guarentees the physical TLB
> hardware is serialized across all CPUs upon return.

Thanks, that's what I wanted to make sure.

Christian.

> It also guarentees GUP slow is serialized due to the page table
> spinlocks.
>
> Jason