Re: [PATCH v4 09/25] iommu: Allow an IDENTITY domain as the default_domain in ARM32

[Jason Gunthorpe <jgg@nvidia.com>]

On Sat, Jun 17, 2023 at 02:38:04PM +0300, Dan Carpenter wrote:

> 8b4eb75ee50e6f Jason Gunthorpe 2023-05-11  1748  static int iommu_get_default_domain_type(struct iommu_group *group,
> 8b4eb75ee50e6f Jason Gunthorpe 2023-05-11  1749  					 int target_type)
> deac0b3bed26bb Joerg Roedel    2020-04-29  1750  {
> ddaf433cac2995 Jason Gunthorpe 2023-06-16  1751  	const struct iommu_ops *ops = dev_iommu_ops(
> ddaf433cac2995 Jason Gunthorpe 2023-06-16  1752  		list_first_entry(&group->devices, struct group_device, list)
> ddaf433cac2995 Jason Gunthorpe 2023-06-16  1753  			->dev);
> 8b4eb75ee50e6f Jason Gunthorpe 2023-05-11  1754  	int best_type = target_type;
> 8b4eb75ee50e6f Jason Gunthorpe 2023-05-11  1755  	struct group_device *gdev;
> 8b4eb75ee50e6f Jason Gunthorpe 2023-05-11  1756  	struct device *last_dev;
> ddaf433cac2995 Jason Gunthorpe 2023-06-16  1757  	int type;
> deac0b3bed26bb Joerg Roedel    2020-04-29  1758  
> 8b4eb75ee50e6f Jason Gunthorpe 2023-05-11  1759  	lockdep_assert_held(&group->mutex);
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1760  
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1761  	/*
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1762  	 * ARM32 drivers supporting CONFIG_ARM_DMA_USE_IOMMU can declare an
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1763  	 * identity_domain and it will automatically become their default
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1764  	 * domain. Later on ARM_DMA_USE_IOMMU will install its UNMANAGED domain.
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1765  	 * Override the selection to IDENTITY if we are sure the driver supports
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1766  	 * it.
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1767  	 */
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1768  	if (IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU) && ops->identity_domain) {
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1769  		type = IOMMU_DOMAIN_IDENTITY;
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1770  		if (best_type && type && best_type != type)
> 03c9e7d1dd3c99 Jason Gunthorpe 2023-06-16  1771  			goto err;
> 
> gdev is uninitialized.

Should be 'return -1;' here, I fixed it up

Thanks,
Jason