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Date:   Wed, 14 Aug 2019 16:50:33 +0200
From:   Corentin Labbe <clabbe.montjoie@gmail.com>
To:     bskeggs@redhat.com, airlied@linux.ie, daniel@ffwll.ch, hch@lst.de,
        m.szyprowski@samsung.com, robin.murphy@arm.com
Cc:     dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
        linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org
Subject: DMA-API: cacheline tracking ENOMEM, dma-debug disabled due to
 nouveau ?
Message-ID: <20190814145033.GA11190@Red>
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Hello

Since lot of release (at least since 4.19), I hit the following error message:
DMA-API: cacheline tracking ENOMEM, dma-debug disabled

After hitting that, I try to check who is creating so many DMA mapping and see:
cat /sys/kernel/debug/dma-api/dump | cut -d' ' -f2 | sort | uniq -c
      6 ahci
    257 e1000e
      6 ehci-pci
   5891 nouveau
     24 uhci_hcd

Does nouveau having this high number of DMA mapping is normal ?

Regards