Date:   Thu, 9 Feb 2023 09:24:14 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     "Tian, Kevin" <kevin.tian@intel.com>
Cc:     Nicolin Chen <nicolinc@nvidia.com>,
        "joro@8bytes.org" <joro@8bytes.org>,
        "will@kernel.org" <will@kernel.org>,
        "robin.murphy@arm.com" <robin.murphy@arm.com>,
        "alex.williamson@redhat.com" <alex.williamson@redhat.com>,
        "shuah@kernel.org" <shuah@kernel.org>,
        "Liu, Yi L" <yi.l.liu@intel.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "iommu@lists.linux.dev" <iommu@lists.linux.dev>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "linux-kselftest@vger.kernel.org" <linux-kselftest@vger.kernel.org>,
        "baolu.lu@linux.intel.com" <baolu.lu@linux.intel.com>
Subject: Re: [PATCH v2 07/10] iommufd/device: Make hwpt_list list_add/del
 symmetric
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On Thu, Feb 09, 2023 at 03:23:47AM +0000, Tian, Kevin wrote:
> > From: Nicolin Chen <nicolinc@nvidia.com>
> > Sent: Wednesday, February 8, 2023 5:18 AM
> > 
> > Because list_del() is together with iopt_table_remove_domain(), it makes
> > sense to have list_add_tail() together with iopt_table_add_domain().
> > 
> > Also place the mutex outside the iommufd_device_do_attach() call, similar
> > to what's in the iommufd_device_auto_get_domain() function.
> > 
> > Co-developed-by: Yi Liu <yi.l.liu@intel.com>
> > Signed-off-by: Yi Liu <yi.l.liu@intel.com>
> > Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> > Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
> 
> shouldn't this be a separate bug fix and backported? double adding a
> list item would certainly clobber the list...

AFAIK there is no bug, this is just reorganizing things

Jason