Re: [PATCH] iommu/dma: Handle MSI mappings separately

On 2019-07-29 16:32, Robin Murphy wrote:

MSI pages must always be mapped into a device's *current* domain, 
which
*might* be the default DMA domain, but might instead be a VFIO domain
with its own MSI cookie. This subtlety got accidentally lost in the
streamlining of __iommu_dma_map(), but rather than reintroduce more
complexity and/or special-casing, it turns out neater to just split 
this
path out entirely.

Since iommu_dma_get_msi_page() already duplicates much of what
__iommu_dma_map() does, it can easily just make the allocation and
mapping calls directly as well. That way we can further streamline 
the
helper back to exclusively operating on DMA domains.

Fixes: b61d271e59d7 ("iommu/dma: Move domain lookup into
__iommu_dma_{map,unmap}")
Reported-by: Shameer Kolothum <redacted>
Reported-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>

With this patch, my TX2 is back in business with a bnx2x device passed
to a guest. FWIW:

Tested-by: Marc Zyngier <maz@kernel.org>

Thanks,

         M.
-- 
Jazz is not dead. It just smells funny...

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel