Subject: Re: [PATCH rc v2 0/5] iommu/arm-smmu-v3: Fix device crash on kdump kernel

From: Jason Gunthorpe <[email-masked]>
Date: Fri, 17 Apr 2026 08:59:53 -0300

On Fri, Apr 17, 2026 at 07:48:46AM +0000, Tian, Kevin wrote:
> is there any report on such systems? It might be informational to include
> a link to the report so it's clear that this series fixes real issues instead of
> a preparation for coming systems...

Yeah, we have an internal report and this was confirmed to fix it.

> btw the DMA is allowed after the previous kernel is hung til the point
> where smmu driver blocks it. In cases where in-fly DMAs are considered
> dangerous to kdump, this series just make it worse instead of creating
> a new issue. While for majority other failures not related to DMAs, 
> unblocking then increases the chance of success...

Right, exactly.

If DMA's are splattering over the kdump carve out memory its is
probably dead no matter what.

Jason