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Date: Mon, 15 Jan 2024 13:19:50 -0400
From: Jason Gunthorpe <jgg@nvidia.com>
To: Yi Liu <yi.l.liu@intel.com>
Cc: joro@8bytes.org, alex.williamson@redhat.com, kevin.tian@intel.com,
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Subject: Re: [PATCH 1/8] iommu: Introduce a replace API for device pasid
Message-ID: <20240115171950.GL734935@nvidia.com>
References: <20231127063428.127436-1-yi.l.liu@intel.com>
 <20231127063428.127436-2-yi.l.liu@intel.com>
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On Sun, Nov 26, 2023 at 10:34:21PM -0800, Yi Liu wrote:
> +int iommu_replace_device_pasid(struct iommu_domain *domain,
> +			       struct device *dev, ioasid_t pasid)
> +{
> +	struct iommu_group *group = dev->iommu_group;
> +	struct iommu_domain *old_domain;
> +	int ret;
> +
> +	if (!domain)
> +		return -EINVAL;
> +
> +	if (!group)
> +		return -ENODEV;
> +
> +	mutex_lock(&group->mutex);
> +	__iommu_remove_group_pasid(group, pasid);

It is not replace if you do remove first.

Replace must just call set_dev_pasid and nothing much else..

Jason