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From:   "Tian, Kevin" <kevin.tian@intel.com>
To:     Jason Gunthorpe <jgg@ziepe.ca>
CC:     Baolu Lu <baolu.lu@linux.intel.com>,
        Joerg Roedel <joro@8bytes.org>,
        "Will Deacon" <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
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        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
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Subject: RE: [PATCH v2 03/12] iommu: Remove unrecoverable fault data
Thread-Topic: [PATCH v2 03/12] iommu: Remove unrecoverable fault data
Thread-Index: AQHZwE5XwmTCizFL9kGoEloX5eLFx6/YPsPQgAE/24CAAA6WQIAHQY4AgABZl1A=
Date:   Wed, 9 Aug 2023 00:01:52 +0000
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> From: Jason Gunthorpe <jgg@ziepe.ca>
> Sent: Wednesday, August 9, 2023 2:40 AM
>=20
> On Fri, Aug 04, 2023 at 03:51:30AM +0000, Tian, Kevin wrote:
> > > From: Baolu Lu <baolu.lu@linux.intel.com>
> > > Sent: Friday, August 4, 2023 10:59 AM
> > >
> > > On 2023/8/3 15:54, Tian, Kevin wrote:
> > > >> From: Lu Baolu<baolu.lu@linux.intel.com>
> > > >> Sent: Thursday, July 27, 2023 1:48 PM
> > > >>
> > > >>   struct iommu_fault {
> > > >>   	__u32	type;
> > > >> -	__u32	padding;
> > > > this padding should be kept.
> > > >
> > >
> > > To keep above 64-bit aligned, right?
> > >
> >
> > yes
>=20
> If it is not uapi we should not explicitly document padding (and __u32
> should be u32). The compiler will add it if it is necessary.
>=20
> If the compiler isn't right for some reason then something else has
> gone wrong.
>=20

I thought this will be used as uAPI later. I'm fine to leave it be and
add the padding when the uAPI is introduced.