Re: Regressions can bus with MCP2515 on sama5d3 connected over SPI stop working on kernel > 5.4.271

["Linux regression tracking (Thorsten Leemhuis)" <regressions@leemhuis.info>]

Hi! Thx for your report!

On 11.03.24 22:55, Daniel Smolik wrote:
> I have found problem with kernel > 5.4.271 (long term) on sama5d3. When
> I config can bus with:
> 
> ip link set can0 type can bitrate 125000 triple-sampling on
> 
> and type
> ifconfig can0 up
> 
> prompt never returns and cannot run eg. ip a (never returns) existing
> ssh connection works but can´t do new one.
> 
> 
>   I have my own daughter  board with can bus driver MCP2515 connected
> over SPI bus. There is
> snippet of my DTB:
> 
>  can0: can@0 {
>                                         compatible = "microchip,mcp2515";
>                                         reg = <0>;
>                                         clocks = <&can0_osc_fixed>;
>                                         interrupt-parent = <&pioD>;
>                                         interrupts = <29
> IRQ_TYPE_EDGE_RISING>;
>                                         spi-max-frequency = <10000000>;
>                                     };
> 
> with this all working  perfect  on long term kernels 4.19.  I try switch
> to newer kernel and latest I get working is 5.4.271.   Kernel 5.5.0
> -5.5.6 I can´t  compile and 5.5.14  is affected with bug.

The two important question here are:

* Is mainline (e.g. 6.8) affected as well? That determines if the
regular developers or the stable team has to look into this.

* Could you bisect the problem (e.g. I assume between 5.4.271 and
5.4.272)? I'm working on a guide that explains this:
https://www.leemhuis.info/files/misc/How%20to%20bisect%20a%20Linux%20kernel%20regression%20%e2%80%94%20The%20Linux%20Kernel%20documentation.html

Ciao, Thorsten