Answering myself ...
On 20/01/2020 23.02, Oliver Hartkopp wrote:
Added some code to check whether dev->ml_priv is NULL:
~/linux$ git diff
diff --git a/net/can/af_can.c b/net/can/af_can.c
index 128d37a4c2e0..6fb4ae4c359e 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -463,6 +463,10 @@ int can_rx_register(struct net *net, struct
net_device *dev, canid_t can_id,
spin_lock_bh(&net->can.rcvlists_lock);
dev_rcv_lists = can_dev_rcv_lists_find(net, dev);
+ if (!dev_rcv_lists) {
+ pr_err("dev_rcv_lists == NULL! %p\n", dev);
+ goto out_unlock;
+ }
rcv_list = can_rcv_list_find(&can_id, &mask, dev_rcv_lists);
rcv->can_id = can_id;
@@ -479,6 +483,7 @@ int can_rx_register(struct net *net, struct
net_device *dev, canid_t can_id,
rcv_lists_stats->rcv_entries++;
rcv_lists_stats->rcv_entries_max =
max(rcv_lists_stats->rcv_entries_max,
rcv_lists_stats->rcv_entries);
+out_unlock:
spin_unlock_bh(&net->can.rcvlists_lock);
return err;
And the output (after some time) is:
[ 758.505841] netlink: 'crash': attribute type 1 has an invalid length.
[ 758.508045] bond7148: (slave vxcan1): The slave device specified does
not support setting the MAC address
[ 758.508057] bond7148: (slave vxcan1): Error -22 calling dev_set_mtu
[ 758.532025] bond10413: (slave vxcan1): The slave device specified
does not support setting the MAC address
[ 758.532043] bond10413: (slave vxcan1): Error -22 calling dev_set_mtu
[ 758.532254] dev_rcv_lists == NULL! 000000006b9d257f
[ 758.547392] netlink: 'crash': attribute type 1 has an invalid length.
[ 758.549310] bond7145: (slave vxcan1): The slave device specified does
not support setting the MAC address
[ 758.549313] bond7145: (slave vxcan1): Error -22 calling dev_set_mtu
[ 758.550464] netlink: 'crash': attribute type 1 has an invalid length.
[ 758.552301] bond7146: (slave vxcan1): The slave device specified does
not support setting the MAC address
So we can see that we get a ml_priv pointer which is NULL which should
not be possible due to this:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/net/can/dev.c#n743
This reference doesn't point to the right code as vxcan has its own
handling do assign ml_priv in vxcan.c .
Btw. the variable 'size' is set two times at the top of
alloc_candev_mqs() depending on echo_skb_max. This looks wrong.
No. It looks right as I did not get behind the ALIGN() macro at first sight.
But it is still open why dev->ml_priv is not set correctly in vxcan.c as
all the settings for .priv_size and in vxcan_setup look fine.
Best regards,
Oliver