Re: [PATCH v5 14/14] iommu/arm-smmu-v3: Report events that belong to devices attached to vIOMMU

From: Jason Gunthorpe
Date: Mon Jan 13 2025 - 14:18:30 EST


On Mon, Jan 13, 2025 at 11:15:21AM -0800, Nicolin Chen wrote:
> On Mon, Jan 13, 2025 at 03:06:41PM -0400, Jason Gunthorpe wrote:
> > On Mon, Jan 13, 2025 at 11:01:10AM -0800, Nicolin Chen wrote:
> >
> > > +/* This is basically iommu_vevent_arm_smmuv3 in u64 for conversion */
> > > +struct arm_vsmmu_evt {
> > > + union {
> > > + u64 evt[EVTQ_ENT_DWORDS];
> > > + struct iommu_vevent_arm_smmuv3 uevt;
> > > + };
> > > +};
> >
> > This doesn't seem right, don't make unions like this
>
> This is copied from the invalidate union though... Any reason why
> this is no longer good for evt v.s. cmd?

In that case it was trying to be really optimal and copy in place,
here we don't care so much..

Jason