Re: [PATCH 1/2] iommu/vt-d: Detach domain before using a private one

[Lu Baolu]

Hi Alex,

On 8/9/19 4:10 AM, Alex Williamson wrote:
> On Tue,  6 Aug 2019 08:14:08 +0800
> Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> wrote:
>
> > When the default domain of a group doesn't work for a device,
> > the iommu driver will try to use a private domain. The domain
> > which was previously attached to the device must be detached.
> >
> > Cc: Ashok Raj <ashok.raj@xxxxxxxxx>
> > Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> > Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
> > Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
> > Fixes: 942067f1b6b97 ("iommu/vt-d: Identify default domains replaced with private")
> > Reported-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
> > Link: https://lkml.org/lkml/2019/8/2/1379
> > Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> > ---
>
> Tested-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
>
> This series resolves the issue I reported against:
>   iommu/vt-d: Cleanup get_valid_domain_for_dev()

Thank you for testing it.

Best regards,
Baolu

> Thanks,
> Alex
>
> >   drivers/iommu/intel-iommu.c | 6 +++++-
> >   1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
> > index 3e22fa6ae8c8..37259b7f95a7 100644
> > --- a/drivers/iommu/intel-iommu.c
> > +++ b/drivers/iommu/intel-iommu.c
> > @@ -3449,6 +3449,7 @@ static bool iommu_need_mapping(struct device *dev)
> >   				dmar_domain = to_dmar_domain(domain);
> >   				dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
> >   			}
> > +			dmar_remove_one_dev_info(dev);
> >   			get_private_domain_for_dev(dev);
> >   		}
> >   
> > @@ -4803,7 +4804,8 @@ static void dmar_remove_one_dev_info(struct device *dev)
> >   
> >   	spin_lock_irqsave(&device_domain_lock, flags);
> >   	info = dev->archdata.iommu;
> > -	__dmar_remove_one_dev_info(info);
> > +	if (info)
> > +		__dmar_remove_one_dev_info(info);
> >   	spin_unlock_irqrestore(&device_domain_lock, flags);
> >   }
> >   
> > @@ -5281,6 +5283,7 @@ static int intel_iommu_add_device(struct device *dev)
> >   		if (device_def_domain_type(dev) == IOMMU_DOMAIN_IDENTITY) {
> >   			ret = iommu_request_dm_for_dev(dev);
> >   			if (ret) {
> > +				dmar_remove_one_dev_info(dev);
> >   				dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
> >   				domain_add_dev_info(si_domain, dev);
> >   				dev_info(dev,
> > @@ -5291,6 +5294,7 @@ static int intel_iommu_add_device(struct device *dev)
> >   		if (device_def_domain_type(dev) == IOMMU_DOMAIN_DMA) {
> >   			ret = iommu_request_dma_domain_for_dev(dev);
> >   			if (ret) {
> > +				dmar_remove_one_dev_info(dev);
> >   				dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
> >   				if (!get_private_domain_for_dev(dev)) {
> >   					dev_warn(dev,