Re: [PATCH net-next v3 3/3] page_pool: fix IOMMU crash when driver has already unbound
From: Christoph Hellwig
Date: Thu Nov 07 2024 - 03:41:52 EST
On Wed, Nov 06, 2024 at 06:56:34PM +0800, Yunsheng Lin wrote:
> > It is a very radical change that page_pool needs to keep track of *ALL* in-flight pages.
>
> I am agreed that it is a radical change, that is why it is targetting net-next
> tree instead of net tree even when there is a Fixes tag for it.
>
> If there is a proper and non-radical way to fix that, I would prefer the
> non-radical way too.
As Robin already correctly pointed out DMA mappings fundamentally can't
outlive the devices they were performed on. So I don't think there will
be much hope for a non-radical fix for this design fault.