RE: swiotlb/caamjr regression (Was: [GIT PULL] (swiotlb) stable/for-linus-5.12)

From: Chanho Park
Date: Sun Jun 20 2021 - 23:48:07 EST


+ Bumyong who is the original author of the patch.

Hi Dominique,

> Thanks!
> (a bit late, but added Chanho Park in Cc...)
>
> I can confirm it also works for our caam problem, as Horia said.
>
> I've also come to term with the use of swiotlb_align_offset() through
> testing, or rather many devices seem to have a 0 mask so it will almost
> always be cancelled out, so if it works for Jianxiong then it's probably
> good enough and I'll just assume that's how the orig_addr has been
> designed...
>
> I think it's missing a couple of checks like the one Linus had in his
> patch, and would be comfortable with something like the attached patch (in
> practice for me exactly the same as the original patch, except I've added
> two checks: offsets smaller than orig addr offset are refused as well as
> offsets bigger than the mapping size)
>
> I'm sorry Jianxiong but would you be willing to take the time to test
> again just to make sure there were no such offsets in your case?
>
>
> If we're good with that I'll send it as an official v2 keeping Chanho's
> from, unless he wants to.
>

Sure. No problem. But, the patch was already stacked on Konrad's tree
and linux-next as well.

https://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb.git/commit/?h=devel/for-linus-5.14&id=33d1641f38f0c327bc3e5c21de585c77a6512bc6

Best Regards,
Chanho Park