Re: [PATCH v7 1/6] iommufd: Support a HWPT without an iommu driver for noiommu

[Jacob Pan <jacob.pan@linux.microsoft.com>]

Hi Kevin,

On Wed, 3 Jun 2026 06:30:57 +0000
"Tian, Kevin" <kevin.tian@intel.com> wrote:

> > From: Jacob Pan <jacob.pan@linux.microsoft.com>
> > Sent: Wednesday, June 3, 2026 1:45 PM
> > 
> > +static const struct iommu_ops *get_iommu_ops(struct iommufd_device
> > *idev)
> > +{
> > +	if (IS_ENABLED(CONFIG_IOMMUFD_NOIOMMU) && !idev->igroup-  
> > >group)  
> > +		return &iommufd_noiommu_ops;
> > +	if (WARN_ON_ONCE(!idev->dev->iommu))
> > +		return NULL;
> > +	return dev_iommu_ops(idev->dev);
> > +}  
> 
> Sashiko gave a valid comment:
> 
> "
> While get_iommu_ops() correctly handles NO-IOMMU devices for
> hw_pagetable allocations, do the vIOMMU and vDevice allocation paths
> also need similar protection against NULL pointer dereferences?
> "
> 
right, will fix in v8.

> with that fixed:
> 
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>