[PATCH 6.1 0865/1146] iommu/sun50i: Remove IOMMU_DOMAIN_IDENTITY

Greg Kroah-Hartman
2022-12-28T16:43:56Z

From: Jason Gunthorpe <jgg@nvidia.com>

[ Upstream commit ef5bb8e7a7127218f826b9ccdf7508e7a339f4c2 ]

This driver treats IOMMU_DOMAIN_IDENTITY the same as UNMANAGED, which
cannot possibly be correct.

UNMANAGED domains are required to start out blocking all DMAs. This seems
to be what this driver does as it allocates a first level 'dt' for the IO
page table that is 0 filled.

Thus UNMANAGED looks like a working IO page table, and so IDENTITY must be
a mistake. Remove it.

Fixes: 4100b8c229b3 ("iommu: Add Allwinner H6 IOMMU driver")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/0-v1-97f0adf27b5e+1f0-s50_identity_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iommu/sun50i-iommu.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/iommu/sun50i-iommu.c b/drivers/iommu/sun50i-iommu.c
index 5cb2d44dfb92..5b585eace3d4 100644
--- a/drivers/iommu/sun50i-iommu.c
+++ b/drivers/iommu/sun50i-iommu.c
@@ -672,7 +672,6 @@ static struct iommu_domain *sun50i_iommu_domain_alloc(unsigned type)
struct sun50i_iommu_domain *sun50i_domain;

if (type != IOMMU_DOMAIN_DMA &&
- type != IOMMU_DOMAIN_IDENTITY &&
type != IOMMU_DOMAIN_UNMANAGED)
return NULL;

--
2.35.1