linux-kernel - Re: [PATCH v1 7/8] iommufd/device: Use iommu_group_replace

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: <Y+FSVoRpVguZUmW9@Asurada-Nvidia>
Date:   Mon, 6 Feb 2023 11:17:42 -0800
From:   Nicolin Chen <nicolinc@...dia.com>
To:     "Tian, Kevin" <kevin.tian@...el.com>
CC:     "jgg@...dia.com" <jgg@...dia.com>,
        "joro@...tes.org" <joro@...tes.org>,
        "will@...nel.org" <will@...nel.org>,
        "robin.murphy@....com" <robin.murphy@....com>,
        "alex.williamson@...hat.com" <alex.williamson@...hat.com>,
        "shuah@...nel.org" <shuah@...nel.org>,
        "Liu, Yi L" <yi.l.liu@...el.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "iommu@...ts.linux.dev" <iommu@...ts.linux.dev>,
        "kvm@...r.kernel.org" <kvm@...r.kernel.org>,
        "linux-kselftest@...r.kernel.org" <linux-kselftest@...r.kernel.org>,
        "baolu.lu@...ux.intel.com" <baolu.lu@...ux.intel.com>
Subject: Re: [PATCH v1 7/8] iommufd/device: Use iommu_group_replace_domain()

On Mon, Feb 06, 2023 at 08:46:04AM +0000, Tian, Kevin wrote:
> > From: Nicolin Chen <nicolinc@...dia.com>
> > Sent: Thursday, February 2, 2023 3:05 PM
> >
> > @@ -246,6 +249,18 @@ static int iommufd_device_do_attach(struct
> > iommufd_device *idev,
> >               }
> >       }
> >
> > +     if (cur_hwpt) {
> > +             /* Replace the cur_hwpt */
> > +             mutex_lock(&cur_hwpt->devices_lock);
> > +             if (cur_hwpt->ioas != hwpt->ioas)
> > +                     iopt_remove_reserved_iova(&cur_hwpt->ioas->iopt,
> > +                                               idev->dev);
> > +             list_del(&cur_hwpt->hwpt_item);
> 
> emmm shouldn't this be done only when the device is the last
> one attached to the hwpt? and if it's the last one you should
> also iopt_table_remove_domain() together with list_del, i.e.
> similar housekeeping as done in iommufd_device_detach().

You are right. I had another patch on top of this series,
moving this list_del() and iopt_table_remove_domain() to
the destroy() callback, so I overlooked.

And I just found that the list_add_del(hwpt_item) in the
IOMMUFD_OBJ_HW_PAGETABLE case doesn't seem to call at the
first device's attachment. So, I think that we might need
my previous "symmetric" patch in this series too.

Will fix in v2. Thanks!

Nic