linux-kernel - Re: [PATCH v8 3/5] iommufd: Add IOMMU_GET_HW

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <ZN7BPMra5fC7YBcs@nvidia.com>
Date:   Thu, 17 Aug 2023 21:54:20 -0300
From:   Jason Gunthorpe <jgg@...dia.com>
To:     "Liu, Yi L" <yi.l.liu@...el.com>
Cc:     Nicolin Chen <nicolinc@...dia.com>,
        "Tian, Kevin" <kevin.tian@...el.com>,
        "joro@...tes.org" <joro@...tes.org>,
        "alex.williamson@...hat.com" <alex.williamson@...hat.com>,
        "robin.murphy@....com" <robin.murphy@....com>,
        "baolu.lu@...ux.intel.com" <baolu.lu@...ux.intel.com>,
        "cohuck@...hat.com" <cohuck@...hat.com>,
        "eric.auger@...hat.com" <eric.auger@...hat.com>,
        "kvm@...r.kernel.org" <kvm@...r.kernel.org>,
        "mjrosato@...ux.ibm.com" <mjrosato@...ux.ibm.com>,
        "chao.p.peng@...ux.intel.com" <chao.p.peng@...ux.intel.com>,
        "yi.y.sun@...ux.intel.com" <yi.y.sun@...ux.intel.com>,
        "peterx@...hat.com" <peterx@...hat.com>,
        "jasowang@...hat.com" <jasowang@...hat.com>,
        "shameerali.kolothum.thodi@...wei.com" 
        <shameerali.kolothum.thodi@...wei.com>,
        "lulu@...hat.com" <lulu@...hat.com>,
        "suravee.suthikulpanit@....com" <suravee.suthikulpanit@....com>,
        "iommu@...ts.linux.dev" <iommu@...ts.linux.dev>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-kselftest@...r.kernel.org" <linux-kselftest@...r.kernel.org>,
        "Duan, Zhenzhong" <zhenzhong.duan@...el.com>
Subject: Re: [PATCH v8 3/5] iommufd: Add IOMMU_GET_HW_INFO

On Fri, Aug 18, 2023 at 12:04:29AM +0000, Liu, Yi L wrote:
> > > > +int iommufd_get_hw_info(struct iommufd_ucmd *ucmd)
> > > > +{
> > > > +     struct iommu_hw_info *cmd = ucmd->cmd;
> > > > +     void __user *user_ptr = u64_to_user_ptr(cmd->data_uptr);
> > > > +     const struct iommu_ops *ops;
> > > > +     struct iommufd_device *idev;
> > > > +     unsigned int data_len;
> > > > +     unsigned int copy_len;
> > > > +     void *data = NULL;
> > [..]
> > > > +     } else {
> > > > +             cmd->out_data_type = IOMMU_HW_INFO_TYPE_NONE;
> > > > +             data_len = 0;
> > > > +             data = NULL;
> > >
> > > data is already initialized as NULL.
> 
> Probably we can set data_len = 0 and the out_data_type to _NONE is
> the top as well. Any preference?

I think it is clear to remove the variable initialization so this
branch is more explicit

Jason