Re: [RFC PATCH v1 00/18] Provide a new two step DMA API mapping API

Christoph Hellwig
2024-07-03T14:35:38Z

On Wed, Jul 03, 2024 at 01:52:53PM +0300, Leon Romanovsky wrote:
> On Wed, Jul 03, 2024 at 07:42:38AM +0200, Christoph Hellwig wrote:
> > I just tried to boot this on my usual qemu test setup with emulated
> > nvme devices, and it dead-loops with messages like this fairly late
> > in the boot cycle:
> >
> > [ 43.826627] iommu: unaligned: iova 0xfff7e000 pa 0x000000010be33650 size 0x1000 min_pagesz 0x1000
> > [ 43.826982] dma_mapping_error -12
> >
> > passing intel_iommu=off instead of intel_iommu=on (expectedly) makes
> > it go away.
>
> Can you please share your kernel command line and qemu?
> On my and Chaitanya setups it works fine.

qemu-system-x86_64 \
-nographic \
-enable-kvm \
-m 6g \
-smp 4 \
-cpu host \
-M q35,kernel-irqchip=split \
-kernel arch/x86/boot/bzImage \
-append "root=/dev/vda console=ttyS0,115200n8 intel_iommu=on" \
-device intel-iommu,intremap=on \
-device ioh3420,multifunction=on,bus=pcie.0,id=port9-0,addr=9.0,chassis=0 \
-blockdev driver=file,cache.direct=on,node-name=root,filename=/home/hch/images/bookworm.img \
-blockdev driver=host_device,cache.direct=on,node-name=test,filename=/dev/nvme0n1p4 \
-device virtio-blk,drive=root \
-device nvme,drive=test,serial=1234