11-03-2025, 09:25 AM
Hey,
I know this is an old post but I think the problem is common enough and hard enough to figure.
So when you see this scenario - Xen kernel starting and then just "Starting kernel" with regards to Linux, or not even see the Xen kernel starting.
I went through that last week with a Cubietruck.
It almost always means no more than your output is going to a different or misconfigured or non-existent console.
It does almost never mean there was a failure to execute your kernel.
In my case, I had to _remove_ the whole set of definitions like dtuart, console=dtuart, earlycons et ceterea.
EVERYTHING. just no special setting for Xen, load the correct DTB of course, and for Linux kernel, plain and simple console=hvc0.
From that moment on, I had Xen boot output on serial, then Linux kernel boot output on serial, then Linux console on serial.
There was other issues, mostly Xen vs Kernel vs. xl toolstack mismatches
A non-Xen enabled kernel (alpine-lts iirc) and a few more stupid mishaps.
But the main and most common issue was simply that I could not find any indication it was booting when in fact it was booting (and then failed of course), and that the serial console setup didn't work in the "oh lets do it super perfectly addressing the device from dt" way or any other, but worked perfectly in the default which i had never tried since all instructions very specific about giving a device tree address. Just try not doing that and see how it goes.
There's also reports that some DTB's have pins inverted and stuff like that, I tried reversing tx+rx cables, nope.
The failing setup is more complex than that, but there's no reason (unless you do it commercially) to look into that when you can just not specify it and be done with it.
Best,
Flo
I know this is an old post but I think the problem is common enough and hard enough to figure.
So when you see this scenario - Xen kernel starting and then just "Starting kernel" with regards to Linux, or not even see the Xen kernel starting.
I went through that last week with a Cubietruck.
It almost always means no more than your output is going to a different or misconfigured or non-existent console.
It does almost never mean there was a failure to execute your kernel.
In my case, I had to _remove_ the whole set of definitions like dtuart, console=dtuart, earlycons et ceterea.
EVERYTHING. just no special setting for Xen, load the correct DTB of course, and for Linux kernel, plain and simple console=hvc0.
From that moment on, I had Xen boot output on serial, then Linux kernel boot output on serial, then Linux console on serial.
There was other issues, mostly Xen vs Kernel vs. xl toolstack mismatches
A non-Xen enabled kernel (alpine-lts iirc) and a few more stupid mishaps.
But the main and most common issue was simply that I could not find any indication it was booting when in fact it was booting (and then failed of course), and that the serial console setup didn't work in the "oh lets do it super perfectly addressing the device from dt" way or any other, but worked perfectly in the default which i had never tried since all instructions very specific about giving a device tree address. Just try not doing that and see how it goes.
There's also reports that some DTB's have pins inverted and stuff like that, I tried reversing tx+rx cables, nope.
The failing setup is more complex than that, but there's no reason (unless you do it commercially) to look into that when you can just not specify it and be done with it.
Best,
Flo
