Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Tue, 8 Aug 2023 15:39:38 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     "Tian, Kevin" <kevin.tian@intel.com>
Cc:     Baolu Lu <baolu.lu@linux.intel.com>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.org>,
        Nicolin Chen <nicolinc@nvidia.com>,
        "Liu, Yi L" <yi.l.liu@intel.com>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        "iommu@lists.linux.dev" <iommu@lists.linux.dev>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 03/12] iommu: Remove unrecoverable fault data
Message-ID: <ZNKL6hGRZT9qfV1K@ziepe.ca>
References: <20230727054837.147050-1-baolu.lu@linux.intel.com>
 <20230727054837.147050-4-baolu.lu@linux.intel.com>
 <BN9PR11MB52767976314CC61A0F8BEFD08C08A@BN9PR11MB5276.namprd11.prod.outlook.com>
 <faad1948-5096-c9d3-616a-cd0f0a4b5876@linux.intel.com>
 <BN9PR11MB527614E61BC257FE113EFE358C09A@BN9PR11MB5276.namprd11.prod.outlook.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <BN9PR11MB527614E61BC257FE113EFE358C09A@BN9PR11MB5276.namprd11.prod.outlook.com>
Precedence: bulk

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

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.

If the compiler isn't right for some reason then something else has
gone wrong.

Jason