Re: [PATCH 5.10 11/38] swiotlb: rework "fix info leak with DMA_FROM_DEVICE"

[Linus Torvalds]

On Sat, Mar 26, 2022 at 3:18 AM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:"
>
> Yes, I've been watching that thread.  This change is already in 5.15 and
> 5.16 kernels, and does solve one known security issue, so it's a tough
> call.

If you're following that thread, you'll have seen that I've reverted
it, and I actually think the security argument was bogus - the whole
commit was due to a misunderstanding of the actual direction of the
data transfer.

But hey, maybe I'm wrong. The only truly uncontested fact is that it
broke the ath9k driver.

           Linus