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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