mcp251x Error during multiple ip link ups/downs

[matihuf]

Describe the bug

Hello,

I work with the CAN bus (simple write and reads works fine) I wanted to prepare automatic detection of the baud rate. The problem occurs when we changing interface settings in a loop. After a few tries, "RTNETLINK Replies: Connection Timeout" appears and the Raspberry Pi hangs.

I founded similar problem at fork but for mcp25xxfd driver msperl#12

Steps to reproduce the behaviour

Connect to a CAN bus device that sends data and run script at Raspberry Pi. I added sleeps to check if this could help

#!/bin/bash
array=(10000 20000 50000 100000 125000 250000 500000 800000 1000000)
can=$1
while true
do
    for i in "${array[@]}"
    do
        echo $i
        sleep 1
        sudo ip link set $can down
        sleep 1
        sudo ip link set $can up type can bitrate $i
        sleep 1
        candump $can -T 100
    done
done

Device (s)

Raspberry Pi CM4 Lite

System

Raspberry Pi reference 2023-10-10
Generated using pi-gen, https://github.com/RPi-Distro/pi-gen, 962bf483c8f326405794827cce8c0313fd5880a8, stage2

Aug 10 2023 15:33:38
Copyright (c) 2012 Broadcom
version 03dc77429335caee083e22ddc8eec09c07f12a7a (clean) (release) (start)

Linux raspberrypi 6.1.0-rpi4-rpi-v8 #1 SMP PREEMPT Debian 1:6.1.54-1+rpt2 (2023-10-05) aarch64 GNU/Linux

Logs

Feb 21 14:40:10 raspberrypi kernel: mcp251x spi0.0: MCP251x didn't enter in config mode
Feb 21 14:40:10 raspberrypi kernel: A link change request failed with some changes committed already. Interface can1 may have been left with an inconsistent configuration, please check.

Additional context

No response

[Mike-M0]

I am facing exactly the same issue, with a Pi spi mcp2515. But only, when it previously was configured on 125k bitrate and any CAN communication is still active.
The first "ip link set up..." ends with a RTNETLINK error, a second "set up" command freezes the Pi.
When disabling the CAN companion after the first failed "set up", the second works and the Pi continues running.