kernel/drivers/net/can/mscan/mscan.c, branch linux-rolling-stable

can: treewide: remove can_change_mtu()

2025-10-17T07:57:13Z

can_change_mtu() became obsolete by commit 23049938605b ("can: populate the minimum and maximum MTU values"). Now that net_device->min_mtu and net_device->max_mtu are populated, all the checks are already done by dev_validate_mtu() in net/core/dev.c. Remove the net_device_ops->ndo_change_mtu() callback of all the physical interfaces, then remove can_change_mtu(). Only keep the vcan_change_mtu() and vxcan_change_mtu() because the virtual interfaces use their own different MTU logic. The only functional change this patch introduces is that now the user will be able to change the MTU even if the interface is up. This does not matter for Classical CAN and CAN FD because their MTU range is composed of only one value, respectively CAN_MTU and CANFD_MTU. For the upcoming CAN XL, the MTU will be configurable within the CANXL_MIN_MTU to CANXL_MAX_MTU range at any time, even if the interface is up. This is consistent with the other net protocols and does not contradict ISO 11898-1:2024 as having a modifiable MTU is a kernel extension. Signed-off-by: Vincent Mailhol Link: https://patch.msgid.link/20251003-remove-can_change_mtu-v1-1-337f8bc21181@kernel.org Signed-off-by: Marc Kleine-Budde

can: mscan: remove unused struct 'mscan_state'

2024-06-20T09:57:39Z

'mscan_state' is unused since the original commit afa17a500a36 ("net/can: add driver for mscan family & mpc52xx_mscan"). Remove it. Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Simon Horman Reviewed-by: Wolfram Sang Link: https://lore.kernel.org/all/20240525232509.191735-1-linux@treblig.org Signed-off-by: Marc Kleine-Budde

can: dev: fix skb drop check

2022-11-07T13:00:27Z

In commit a6d190f8c767 ("can: skb: drop tx skb if in listen only mode") the priv->ctrlmode element is read even on virtual CAN interfaces that do not create the struct can_priv at startup. This out-of-bounds read may lead to CAN frame drops for virtual CAN interfaces like vcan and vxcan. This patch mainly reverts the original commit and adds a new helper for CAN interface drivers that provide the required information in struct can_priv. Fixes: a6d190f8c767 ("can: skb: drop tx skb if in listen only mode") Reported-by: Dariusz Stojaczyk Cc: Vincent Mailhol Cc: Max Staudt Signed-off-by: Oliver Hartkopp Acked-by: Vincent Mailhol Link: https://lore.kernel.org/all/20221102095431.36831-1-socketcan@hartkopp.net Cc: stable@vger.kernel.org # 6.0.x [mkl: patch pch_can, too] Signed-off-by: Marc Kleine-Budde

can: tree-wide: advertise software timestamping capabilities

2022-07-28T09:44:01Z

Currently, some CAN drivers support hardware timestamping, some do not. But userland has no method to query which features are supported (aside maybe of getting RX messages and observe whether or not hardware timestamps stay at zero). The canonical way for a network driver to advertised what kind of timestamping it supports is to implement ethtool_ops::get_ts_info(). This patch only targets the CAN drivers which *do not* support hardware timestamping. For each of those CAN drivers, implement the get_ts_info() using the generic ethtool_op_get_ts_info(). This way, userland can do: | $ ethtool --show-time-stamping canX to confirm the device timestamping capacities. N.B. the drivers which support hardware timestamping will be migrated in separate patches. Signed-off-by: Vincent Mailhol Link: https://lore.kernel.org/all/20220727101641.198847-6-mailhol.vincent@wanadoo.fr [mkl: mscan: add missing mscan_ethtool_ops] Signed-off-by: Marc Kleine-Budde

can: can-dev: move to netif_napi_add_weight()

2022-05-19T20:11:28Z

We want to remove the weight argument from the basic version of the netif_napi_add() call. Move all the callers in drivers/net/can that pass a custom weight (i.e. not NAPI_POLL_WEIGHT or 64) to the netif_napi_add_weight() API. Link: https://lore.kernel.org/all/20220517002345.1812104-1-kuba@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Marc Kleine-Budde

can: do not increase tx_bytes statistics for RTR frames

2022-01-05T11:09:05Z

The actual payload length of the CAN Remote Transmission Request (RTR) frames is always 0, i.e. no payload is transmitted on the wire. However, those RTR frames still use the DLC to indicate the length of the requested frame. As such, net_device_stats::tx_bytes should not be increased when sending RTR frames. The function can_get_echo_skb() already returns the correct length, even for RTR frames (c.f. [1]). However, for historical reasons, the drivers do not use can_get_echo_skb()'s return value and instead, most of them store a temporary length (or dlc) in some local structure or array. Using the return value of can_get_echo_skb() solves the issue. After doing this, such length/dlc fields become unused and so this patch does the adequate cleaning when needed. This patch fixes all the CAN drivers. Finally, can_get_echo_skb() is decorated with the __must_check attribute in order to force future drivers to correctly use its return value (else the compiler would emit a warning). [1] commit ed3320cec279 ("can: dev: __can_get_echo_skb(): fix real payload length return value for RTR frames") Link: https://lore.kernel.org/all/20211207121531.42941-6-mailhol.vincent@wanadoo.fr Cc: Nicolas Ferre Cc: Alexandre Belloni Cc: Ludovic Desroches Cc: Maxime Ripard Cc: Chen-Yu Tsai Cc: Jernej Skrabec Cc: Yasushi SHOJI Cc: Oliver Hartkopp Cc: Stephane Grosjean Cc: Andreas Larsson Tested-by: Jimmy Assarsson # kvaser Signed-off-by: Vincent Mailhol Acked-by: Stefan Mätje # esd_usb2 Tested-by: Stefan Mätje # esd_usb2 [mkl: add conversion for grcan] Signed-off-by: Marc Kleine-Budde

can: do not increase rx_bytes statistics for RTR frames

2022-01-05T11:09:05Z

can: do not increase rx statistics when generating a CAN rx error message frame

2022-01-05T11:09:05Z

The CAN error message frames (i.e. error skb) are an interface specific to socket CAN. The payload of the CAN error message frames does not correspond to any actual data sent on the wire. Only an error flag and a delimiter are transmitted when an error occurs (c.f. ISO 11898-1 section 10.4.4.2 "Error flag"). For this reason, it makes no sense to increment the rx_packets and rx_bytes fields of struct net_device_stats because no actual payload were transmitted on the wire. This patch fixes all the CAN drivers. Link: https://lore.kernel.org/all/20211207121531.42941-2-mailhol.vincent@wanadoo.fr CC: Marc Kleine-Budde CC: Nicolas Ferre CC: Alexandre Belloni CC: Ludovic Desroches CC: Chandrasekar Ramakrishnan CC: Maxime Ripard CC: Chen-Yu Tsai CC: Jernej Skrabec CC: Appana Durga Kedareswara rao CC: Naga Sureshkumar Relli CC: Michal Simek CC: Stephane Grosjean Tested-by: Jimmy Assarsson # kvaser Signed-off-by: Vincent Mailhol Acked-by: Stefan Mätje # esd_usb2 Tested-by: Stefan Mätje # esd_usb2 Signed-off-by: Marc Kleine-Budde

can: dev: can_get_echo_skb(): extend to return can frame length

2021-01-14T07:43:43Z

In order to implement byte queue limits (bql) in CAN drivers, the length of the CAN frame needs to be passed into the networking stack after queueing and after transmission completion. To avoid to calculate this length twice, extend can_get_echo_skb() to return that value. Convert all users of this function, too. Reviewed-by: Vincent Mailhol Link: https://lore.kernel.org/r/20210111141930.693847-14-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde

can: dev: can_put_echo_skb(): extend to handle frame_len

2021-01-14T07:43:43Z

Add a frame_len argument to can_put_echo_skb() which is used to save length of the CAN frame into field frame_len of struct can_skb_priv so that it can be later used after transmission completion. Convert all users of this function, too. Drivers which implement BQL call can_put_echo_skb() with the output of can_skb_get_frame_len(skb) and drivers which do not simply pass zero as an input (in the same way that NULL would be given to can_get_echo_skb()). This way, we have a nice symmetry between the two echo functions. Link: https://lore.kernel.org/r/20210111061335.39983-1-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde Reviewed-by: Vincent Mailhol Link: https://lore.kernel.org/r/20210111141930.693847-13-mkl@pengutronix.de Signed-off-by: Vincent Mailhol