[PATCH v3 6/6] iommu: Propagate ret for a potential soft failure EINVAL

[Tian, Kevin]

> From: Nicolin Chen <nicolinc at nvidia.com>
> Sent: Thursday, September 15, 2022 3:59 PM
> 
> Following the new rules in include/linux/iommu.h kdocs, EINVAL now can be
> used to indicate that domain and device are incompatible by a caller that
> treats it as a soft failure and tries attaching to another domain.
> 
> Either mtk_iommu or virtio driver has a place that returns a hard failure
> instead of the return value from the function call, where an incompatible
> errno EINVAL could potentially occur.

in both cases there is no EINVAL returned from the calling stack

IMHO error propagation is the right way even w/o talking about EINVAL
otherwise we may miss ENOMEM etc.

> 
> Propagate the real return value to not miss a potential soft failure.
> 
> Signed-off-by: Nicolin Chen <nicolinc at nvidia.com>

Apart from that comment,

Reviewed-by: Kevin Tian <kevin.tian at intel.com>