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X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Sep 2021 16:32:38.8005 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: a2296c37-3905-4688-12f6-08d9779d444d X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.112.35];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: CO1NAM11FT022.eop-nam11.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB3662 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Sep 14, 2021 at 08:07:46AM -0700, Jakub Kicinski wrote: > On Tue, 14 Sep 2021 17:54:39 +0300 Eli Cohen wrote: > > On Tue, Sep 14, 2021 at 07:26:29AM -0700, Jakub Kicinski wrote: > > > On Tue, 14 Sep 2021 09:05:00 +0300 Eli Cohen wrote: > > > > I see the same assert and the same comment, "All callback list access > > > > should be protected by RTNL.", in the following locations > > > > > > > > drivers/net/ethernet/broadcom/bnxt/bnxt_tc.c:1873 > > > > drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c:303 > > > > drivers/net/ethernet/netronome/nfp/flower/offload.c:1770 > > > > > > > > I assume the source of this comment is the same. Can you guys explain > > > > why is this necessary? > > > > > > Because most drivers (all but mlx5?) depend on rtnl_lock for > > > serializing tc offload operations. > > > > > > > But the assert I am referring to is called as part of setting up the > > callback that will be used for offload operations, e.g. for adding a new > > filter with tc. It's not the actual filter insetion code. > > > > And as far as I can see this call sequence is already serialized by > > flow_indr_block_lock. > > Hm, indeed, should've looked at the code. There doesn't seem to be > anything on the driver side this is protecting. The assert was added > before the flow/nftables rewrite of the infra, perhaps that's the > answer. IOW the lock did not exist back then. ok, so if there are no objections by my next morning, I will post a patch to remove these.