Re: [PATCH v3 3/4] scsi: core: Cap shost max_sectors according to DMA optimum mapping limits

Bart Van Assche
2022-06-09T20:34:44Z

On 6/9/22 10:54, John Garry wrote:
> ok, but do you have a system where the UFS host controller is behind an
> IOMMU? I had the impression that UFS controllers would be mostly found
> in embedded systems and IOMMUs are not as common on there.

Modern phones have an IOMMU. Below one can find an example from a Pixel
6 phone. The UFS storage controller is not controller by the IOMMU as
far as I can see but I wouldn't be surprised if the security team would
ask us one day to enable the IOMMU for the UFS controller.

# (cd /sys/class/iommu && ls */devices)
1a090000.sysmmu/devices:
19000000.aoc

1a510000.sysmmu/devices:
1a440000.lwis_csi

1a540000.sysmmu/devices:
1aa40000.lwis_pdp

1a880000.sysmmu/devices:
1a840000.lwis_g3aa

1ad00000.sysmmu/devices:
1ac40000.lwis_ipp 1ac80000.lwis_gtnr_align

1b080000.sysmmu/devices:
1b450000.lwis_itp

1b780000.sysmmu/devices:

1b7b0000.sysmmu/devices:
1b760000.lwis_mcsc

1b7e0000.sysmmu/devices:

1baa0000.sysmmu/devices:
1a4e0000.lwis_votf 1ba40000.lwis_gdc

1bad0000.sysmmu/devices:
1ba60000.lwis_gdc

1bb00000.sysmmu/devices:
1ba80000.lwis_scsc

1bc70000.sysmmu/devices:
1bc40000.lwis_gtnr_merge

1bca0000.sysmmu/devices:

1bcd0000.sysmmu/devices:

1bd00000.sysmmu/devices:

1bd30000.sysmmu/devices:

1c100000.sysmmu/devices:
1c300000.drmdecon 1c302000.drmdecon

1c110000.sysmmu/devices:

1c120000.sysmmu/devices:

1c660000.sysmmu/devices:
1c640000.g2d

1c690000.sysmmu/devices:

1c710000.sysmmu/devices:
1c700000.smfc

1c870000.sysmmu/devices:
1c8d0000.MFC-0 mfc

1c8a0000.sysmmu/devices:

1ca40000.sysmmu/devices:
1cb00000.bigocean

1cc40000.sysmmu/devices:
1ce00000.abrolhos

Bart.