Re: [PATCH v8 0/6] iommu/dma: s390 DMA API conversion and optimized IOTLB flushing

[Niklas Schnelle]

On Fri, 2023-05-12 at 07:29 -0700, Christoph Hellwig wrote:
> On Fri, Mar 10, 2023 at 05:07:45PM +0100, Niklas Schnelle wrote:
> > Hi All,
> > 
> > This patch series converts s390's PCI support from its platform specific DMA
> > API implementation in arch/s390/pci/pci_dma.c to the common DMA IOMMU layer.
> > The conversion itself is done in patches 3-4 with patch 2 providing the final
> > necessary IOMMU driver improvement to handle s390's special IOTLB flush
> > out-of-resource indication in virtualized environments. Patches 1-2 may be
> > applied independently. The conversion itself only touches the s390 IOMMU driver
> > and s390 arch code moving over remaining functions from the s390 DMA API
> > implementation. No changes to common code are necessary.
> 
> It looks like this still hasn't made it upstream as of 6.4-rc1.  What's
> holding this series up?
> 

I think with all the IOMMUFD work going on this got starved out of
reviewer resources. I didn't have any open todos but I guess there is
still some review needed around how the IOMMU driver tells the dma-
iommu that it expects IOTLB flushes to be slow requiring a larger
single flush queue. There was also a small conflict with commit
49a22aae7d9c ("iommu: Replace device_lock() with group->mutex") that
prevented this from applying to current upstream so I've just now sent
out a v9 rebased on v6.4-rc2.

Thanks,
Niklas