5.4-stable review patch. If anyone has any objections, please let me know.
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From: Ido Schimmel idosch@nvidia.com
[ Upstream commit b377add0f0117409c418ddd6504bd682ebe0bf79 ]
Both the function that migrates all the chunks within a region and the function that migrates all the entries within a chunk call list_first_entry() on the respective lists without checking that the lists are not empty. This is incorrect usage of the API, which leads to the following warning [1].
Fix by returning if the lists are empty as there is nothing to migrate in this case.
[1] WARNING: CPU: 0 PID: 6437 at drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c:1266 mlxsw_sp_acl_tcam_vchunk_migrate_all+0x1f1/0> Modules linked in: CPU: 0 PID: 6437 Comm: kworker/0:37 Not tainted 6.9.0-rc3-custom-00883-g94a65f079ef6 #39 Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019 Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work RIP: 0010:mlxsw_sp_acl_tcam_vchunk_migrate_all+0x1f1/0x2c0 [...] Call Trace: <TASK> mlxsw_sp_acl_tcam_vregion_rehash_work+0x6c/0x4a0 process_one_work+0x151/0x370 worker_thread+0x2cb/0x3e0 kthread+0xd0/0x100 ret_from_fork+0x34/0x50 ret_from_fork_asm+0x1a/0x30 </TASK>
Fixes: 6f9579d4e302 ("mlxsw: spectrum_acl: Remember where to continue rehash migration") Signed-off-by: Ido Schimmel idosch@nvidia.com Tested-by: Alexander Zubkov green@qrator.net Reviewed-by: Petr Machata petrm@nvidia.com Signed-off-by: Petr Machata petrm@nvidia.com Reviewed-by: Simon Horman horms@kernel.org Link: https://lore.kernel.org/r/4628e9a22d1d84818e28310abbbc498e7bc31bc9.171379710... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c index 26042c859cf68..89ce9b1233bd9 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.c @@ -1325,6 +1325,9 @@ mlxsw_sp_acl_tcam_vchunk_migrate_one(struct mlxsw_sp *mlxsw_sp, return 0; }
+ if (list_empty(&vchunk->ventry_list)) + goto out; + /* If the migration got interrupted, we have the ventry to start from * stored in context. */ @@ -1376,6 +1379,7 @@ mlxsw_sp_acl_tcam_vchunk_migrate_one(struct mlxsw_sp *mlxsw_sp, } }
+out: mlxsw_sp_acl_tcam_vchunk_migrate_end(mlxsw_sp, vchunk, ctx); return 0; } @@ -1389,6 +1393,9 @@ mlxsw_sp_acl_tcam_vchunk_migrate_all(struct mlxsw_sp *mlxsw_sp, struct mlxsw_sp_acl_tcam_vchunk *vchunk; int err;
+ if (list_empty(&vregion->vchunk_list)) + return 0; + /* If the migration got interrupted, we have the vchunk * we are working on stored in context. */