This is a note to let you know that I've just added the patch titled mlxsw: spectrum: Fix refcount bug on span entries to the 4.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mlxsw-spectrum-fix-refcount-bug-on-span-entries.patch and it can be found in the queue-4.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Fri Nov 18 11:35:46 CET 2016 From: Yotam Gigi <yotamg@xxxxxxxxxxxx> Date: Fri, 11 Nov 2016 16:34:25 +0100 Subject: mlxsw: spectrum: Fix refcount bug on span entries From: Yotam Gigi <yotamg@xxxxxxxxxxxx> [ Upstream commit 2d644d4c7506646f9c4a2afceb7fd5f030bc0c9f ] When binding port to a newly created span entry, its refcount is initialized to zero even though it has a bound port. That leads to unexpected behaviour when the user tries to delete that port from the span entry. Fix this by initializing the reference count to 1. Also add a warning to put function. Fixes: 763b4b70afcd ("mlxsw: spectrum: Add support in matchall mirror TC offloading") Signed-off-by: Yotam Gigi <yotamg@xxxxxxxxxxxx> Reviewed-by: Ido Schimmel <idosch@xxxxxxxxxxxx> Signed-off-by: Jiri Pirko <jiri@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/mellanox/mlxsw/spectrum.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c @@ -231,7 +231,7 @@ mlxsw_sp_span_entry_create(struct mlxsw_ span_entry->used = true; span_entry->id = index; - span_entry->ref_count = 0; + span_entry->ref_count = 1; span_entry->local_port = local_port; return span_entry; } @@ -268,6 +268,7 @@ struct mlxsw_sp_span_entry *mlxsw_sp_spa span_entry = mlxsw_sp_span_entry_find(port); if (span_entry) { + /* Already exists, just take a reference */ span_entry->ref_count++; return span_entry; } @@ -278,6 +279,7 @@ struct mlxsw_sp_span_entry *mlxsw_sp_spa static int mlxsw_sp_span_entry_put(struct mlxsw_sp *mlxsw_sp, struct mlxsw_sp_span_entry *span_entry) { + WARN_ON(!span_entry->ref_count); if (--span_entry->ref_count == 0) mlxsw_sp_span_entry_destroy(mlxsw_sp, span_entry); return 0; Patches currently in stable-queue which might be from yotamg@xxxxxxxxxxxx are queue-4.8/mlxsw-spectrum-fix-refcount-bug-on-span-entries.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html