Re: [PATCH v2 05/11] iommu/sva: Assign a PASID to mm on PASID allocation and free it on mm exit

[Fenghua Yu]

Hi, Thomas,

On Mon, Jan 24, 2022 at 09:36:00PM +0100, Thomas Gleixner wrote:
> On Mon, Jan 24 2022 at 21:21, Thomas Gleixner wrote:
> >
> > Hrm. This is odd.
> >
> >> +/* Associate a PASID with an mm_struct: */
> >> +static inline void mm_pasid_get(struct mm_struct *mm, u32 pasid)
> >> +{
> >> +	mm->pasid = pasid;
> >> +}
> >
> > This does not get anything. It sets the allocated PASID in the mm. The
> > refcount on the PASID was already taken by the allocation. So this
> > should be mm_pasid_set() or mm_pasid_install(), right?
> 
> And as a result of all this ioasid_get() is now left without users...
> 
> Thanks,

Ah. This patch should remove ioasid_get(). So I will change this patch
as follows:

1. Remove ioasid_get() because it's not used any more when IOASID's
   refcount is set to 1 once the IOASID is allocated and is freed on mm exit.
2. Change mm_pasid_get() to mm_pasid_set().

Will that work?

Thanks.

-Fenghua