linux/drivers/net/can, branch for-next

can: m_can: fix missed interrupts with m_can_pci

2024-12-18T08:30:52Z

The interrupt line of PCI devices is interpreted as edge-triggered, however the interrupt signal of the m_can controller integrated in Intel Elkhart Lake CPUs appears to be generated level-triggered. Consider the following sequence of events: - IR register is read, interrupt X is set - A new interrupt Y is triggered in the m_can controller - IR register is written to acknowledge interrupt X. Y remains set in IR As at no point in this sequence no interrupt flag is set in IR, the m_can interrupt line will never become deasserted, and no edge will ever be observed to trigger another run of the ISR. This was observed to result in the TX queue of the EHL m_can to get stuck under high load, because frames were queued to the hardware in m_can_start_xmit(), but m_can_finish_tx() was never run to account for their successful transmission. On an Elkhart Lake based board with the two CAN interfaces connected to each other, the following script can reproduce the issue: ip link set can0 up type can bitrate 1000000 ip link set can1 up type can bitrate 1000000 cangen can0 -g 2 -I 000 -L 8 & cangen can0 -g 2 -I 001 -L 8 & cangen can0 -g 2 -I 002 -L 8 & cangen can0 -g 2 -I 003 -L 8 & cangen can0 -g 2 -I 004 -L 8 & cangen can0 -g 2 -I 005 -L 8 & cangen can0 -g 2 -I 006 -L 8 & cangen can0 -g 2 -I 007 -L 8 & cangen can1 -g 2 -I 100 -L 8 & cangen can1 -g 2 -I 101 -L 8 & cangen can1 -g 2 -I 102 -L 8 & cangen can1 -g 2 -I 103 -L 8 & cangen can1 -g 2 -I 104 -L 8 & cangen can1 -g 2 -I 105 -L 8 & cangen can1 -g 2 -I 106 -L 8 & cangen can1 -g 2 -I 107 -L 8 & stress-ng --matrix 0 & To fix the issue, repeatedly read and acknowledge interrupts at the start of the ISR until no interrupt flags are set, so the next incoming interrupt will also result in an edge on the interrupt line. While we have received a report that even with this patch, the TX queue can become stuck under certain (currently unknown) circumstances on the Elkhart Lake, this patch completely fixes the issue with the above reproducer, and it is unclear whether the remaining issue has a similar cause at all. Fixes: cab7ffc0324f ("can: m_can: add PCI glue driver for Intel Elkhart Lake") Signed-off-by: Matthias Schiffer Reviewed-by: Markus Schneider-Pargmann Link: https://patch.msgid.link/fdf0439c51bcb3a46c21e9fb21c7f1d06363be84.1728288535.git.matthias.schiffer@ew.tq-group.com Signed-off-by: Marc Kleine-Budde

can: m_can: set init flag earlier in probe

2024-12-18T08:30:52Z

While an m_can controller usually already has the init flag from a hardware reset, no such reset happens on the integrated m_can_pci of the Intel Elkhart Lake. If the CAN controller is found in an active state, m_can_dev_setup() would fail because m_can_niso_supported() calls m_can_cccr_update_bits(), which refuses to modify any other configuration bits when CCCR_INIT is not set. To avoid this issue, set CCCR_INIT before attempting to modify any other configuration flags. Fixes: cd5a46ce6fa6 ("can: m_can: don't enable transceiver when probing") Signed-off-by: Matthias Schiffer Reviewed-by: Markus Schneider-Pargmann Link: https://patch.msgid.link/e247f331cb72829fcbdfda74f31a59cbad1a6006.1728288535.git.matthias.schiffer@ew.tq-group.com Signed-off-by: Marc Kleine-Budde

rtnetlink: fix double call of rtnl_link_get_net_ifla()

2024-12-03T10:29:29Z

Currently rtnl_link_get_net_ifla() gets called twice when we create peer devices, once in rtnl_add_peer_net() and once in each ->newlink() implementation. This looks safer, however, it leads to a classic Time-of-Check to Time-of-Use (TOCTOU) bug since IFLA_NET_NS_PID is very dynamic. And because of the lack of checking error pointer of the second call, it also leads to a kernel crash as reported by syzbot. Fix this by getting rid of the second call, which already becomes redudant after Kuniyuki's work. We have to propagate the result of the first rtnl_link_get_net_ifla() down to each ->newlink(). Reported-by: syzbot+21ba4d5adff0b6a7cfc6@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=21ba4d5adff0b6a7cfc6 Fixes: 0eb87b02a705 ("veth: Set VETH_INFO_PEER to veth_link_ops.peer_type.") Fixes: 6b84e558e95d ("vxcan: Set VXCAN_INFO_PEER to vxcan_link_ops.peer_type.") Fixes: fefd5d082172 ("netkit: Set IFLA_NETKIT_PEER_INFO to netkit_link_ops.peer_type.") Cc: Kuniyuki Iwashima Signed-off-by: Cong Wang Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20241129212519.825567-1-xiyou.wangcong@gmail.com Signed-off-by: Paolo Abeni

can: mcp251xfd: mcp251xfd_get_tef_len(): work around erratum DS80000789E 6.

2024-11-26T10:42:32Z

Commit b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround broken TEF FIFO tail index erratum") introduced mcp251xfd_get_tef_len() to get the number of unhandled transmit events from the Transmit Event FIFO (TEF). As the TEF has no head index, the driver uses the TX-FIFO's tail index instead, assuming that send frames are completed. When calculating the number of unhandled TEF events, that commit didn't take mcp2518fd erratum DS80000789E 6. into account. According to that erratum, the FIFOCI bits of a FIFOSTA register, here the TX-FIFO tail index might be corrupted. However here it seems the bit indicating that the TX-FIFO is empty (MCP251XFD_REG_FIFOSTA_TFERFFIF) is not correct while the TX-FIFO tail index is. Assume that the TX-FIFO is indeed empty if: - Chip's head and tail index are equal (len == 0). - The TX-FIFO is less than half full. (The TX-FIFO empty case has already been checked at the beginning of this function.) - No free buffers in the TX ring. If the TX-FIFO is assumed to be empty, assume that the TEF is full and return the number of elements in the TX-FIFO (which equals the number of TEF elements). If these assumptions are false, the driver might read to many objects from the TEF. mcp251xfd_handle_tefif_one() checks the sequence numbers and will refuse to process old events. Reported-by: Renjaya Raga Zenta Closes: https://patch.msgid.link/CAJ7t6HgaeQ3a_OtfszezU=zB-FqiZXqrnATJ3UujNoQJJf7GgA@mail.gmail.com Fixes: b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround broken TEF FIFO tail index erratum") Tested-by: Renjaya Raga Zenta Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20241126-mcp251xfd-fix-length-calculation-v2-1-c2ed516ed6ba@pengutronix.de Signed-off-by: Marc Kleine-Budde

can: f81604: f81604_handle_can_bus_errors(): fix {rx,tx}_errors statistics

2024-11-26T09:51:12Z

The f81604_handle_can_bus_errors() function only incremented the receive error counter and never the transmit error counter, even if the ECC_DIR flag reported that an error had occurred during transmission. Increment the receive/transmit error counter based on the value of the ECC_DIR flag. Fixes: 88da17436973 ("can: usb: f81604: add Fintek F81604 support") Signed-off-by: Dario Binacchi Link: https://patch.msgid.link/20241122221650.633981-13-dario.binacchi@amarulasolutions.com Signed-off-by: Marc Kleine-Budde

can: ems_usb: ems_usb_rx_err(): fix {rx,tx}_errors statistics

2024-11-26T09:51:06Z

The ems_usb_rx_err() function only incremented the receive error counter and never the transmit error counter, even if the ECC_DIR flag reported that an error had occurred during transmission. Increment the receive/transmit error counter based on the value of the ECC_DIR flag. Fixes: 702171adeed3 ("ems_usb: Added support for EMS CPC-USB/ARM7 CAN/USB interface") Signed-off-by: Dario Binacchi Link: https://patch.msgid.link/20241122221650.633981-12-dario.binacchi@amarulasolutions.com Signed-off-by: Marc Kleine-Budde

can: sun4i_can: sun4i_can_err(): fix {rx,tx}_errors statistics

2024-11-26T09:51:00Z

The sun4i_can_err() function only incremented the receive error counter and never the transmit error counter, even if the STA_ERR_DIR flag reported that an error had occurred during transmission. Increment the receive/transmit error counter based on the value of the STA_ERR_DIR flag. Fixes: 0738eff14d81 ("can: Allwinner A10/A20 CAN Controller support - Kernel module") Signed-off-by: Dario Binacchi Link: https://patch.msgid.link/20241122221650.633981-11-dario.binacchi@amarulasolutions.com Signed-off-by: Marc Kleine-Budde

can: sja1000: sja1000_err(): fix {rx,tx}_errors statistics

2024-11-26T09:50:54Z

The sja1000_err() function only incremented the receive error counter and never the transmit error counter, even if the ECC_DIR flag reported that an error had occurred during transmission. Increment the receive/transmit error counter based on the value of the ECC_DIR flag. Fixes: 429da1cc841b ("can: Driver for the SJA1000 CAN controller") Signed-off-by: Dario Binacchi Link: https://patch.msgid.link/20241122221650.633981-10-dario.binacchi@amarulasolutions.com Signed-off-by: Marc Kleine-Budde

can: hi311x: hi3110_can_ist(): fix {rx,tx}_errors statistics

2024-11-26T09:50:48Z

The hi3110_can_ist() function was incorrectly incrementing only the receive error counter, even in cases of bit or acknowledgment errors that occur during transmission. The fix the issue by incrementing the appropriate counter based on the type of error. Fixes: 57e83fb9b746 ("can: hi311x: Add Holt HI-311x CAN driver") Signed-off-by: Dario Binacchi Link: https://patch.msgid.link/20241122221650.633981-9-dario.binacchi@amarulasolutions.com Signed-off-by: Marc Kleine-Budde

can: ifi_canfd: ifi_canfd_handle_lec_err(): fix {rx,tx}_errors statistics

2024-11-26T09:50:40Z

The ifi_canfd_handle_lec_err() function was incorrectly incrementing only the receive error counter, even in cases of bit or acknowledgment errors that occur during transmission. Fix the issue by incrementing the appropriate counter based on the type of error. Fixes: 5bbd655a8bd0 ("can: ifi: Add more detailed error reporting") Signed-off-by: Dario Binacchi Reviewed-by: Marek Vasut Link: https://patch.msgid.link/20241122221650.633981-8-dario.binacchi@amarulasolutions.com Signed-off-by: Marc Kleine-Budde