RE: [PATCH v8 16/24] iommufd/device: Add iommufd_access_detach() API

["Liu, Yi L" <yi.l.liu@intel.com>]

> From: Nicolin Chen <nicolinc@nvidia.com>
> Sent: Tuesday, March 28, 2023 11:55 PM
> 
> On Mon, Mar 27, 2023 at 07:23:57PM -0700, Jon Pan-Doh wrote:
> > External email: Use caution opening links or attachments
> >
> >
> > On 2023/3/27 02:40, Yi Liu wrote:
> > > diff --git a/drivers/iommu/iommufd/iommufd_private.h
> b/drivers/iommu/iommufd/iommufd_private.h
> > > index 2e6e8e217cce..ec2ce3ef187d 100644
> > > --- a/drivers/iommu/iommufd/iommufd_private.h
> > > +++ b/drivers/iommu/iommufd/iommufd_private.h
> > > @@ -263,6 +263,8 @@ struct iommufd_access {
> > >       struct iommufd_object obj;
> > >       struct iommufd_ctx *ictx;
> > >       struct iommufd_ioas *ioas;
> > > +     struct iommufd_ioas *ioas_unpin;
> > > +     struct mutex ioas_lock;
> > >       const struct iommufd_access_ops *ops;
> > >       void *data;
> > >       unsigned long iova_alignment;
> >
> > I think you may need to initialize ioas_lock. I got lockdep warnings running
> > iommufd selftests against this patch. Those went away when I added
> mutex_init().
> >
> > ---
> >  drivers/iommu/iommufd/device.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/iommu/iommufd/device.c
> b/drivers/iommu/iommufd/device.c
> > index f0522d80919d..0eaae60f3537 100644
> > --- a/drivers/iommu/iommufd/device.c
> > +++ b/drivers/iommu/iommufd/device.c
> > @@ -474,6 +474,7 @@ iommufd_access_create(struct iommufd_ctx *ictx,
> >         iommufd_ctx_get(ictx);
> >         iommufd_object_finalize(ictx, &access->obj);
> >         *id = access->obj.id;
> > +       mutex_init(&access->ioas_lock);
> >         return access;
> >  }
> >  EXPORT_SYMBOL_NS_GPL(iommufd_access_create, IOMMUFD);
> > --
> > 2.40.0.348.gf938b09366-goog
> 
> Yes... I think I lost that when splitting the changes.
> 
> Yi, can you help add this in the next version?

Sure. 😊

Regards,
Yi Liu