Re: serial console and comconsole in FreeBSD arm64

On Mon, May 30, 2022, 3:31 AM Souradeep Chakrabarti <
schakrabarti@microsoft.com> wrote:

> Hi,
>
>
>
> I am trying to access virtual serial console via Putty and in 13.0 it is
> not working
>
> for both x86 and arm64.
>
>
>
> It is very easy to reproduce:
>
> 1) In Windows Hyper-V set a  FreeBSD 13.0 VM
>
> 2) Use Powershell in Admin privileged mode and run following:
>
>                 Set-VMComPort -VMName <vm_name> -number 1 -path
> \\.\pipe\Testpipe
>
> 2) In another Powershell with Admin privilege run following:
>
>                 Set-VMFirmware -VMName <VM name>  --ConsoleMode COM1
>
> 3) start the VM and open putty to connect the \\.\pipe\Testpipe in serial
> mode.
>
> No output will be seen on putty.
>
Not even from the boot loader? That sure sounds like the automatic fallback
to simple text output isn't happening.

What does:
% sudo efivar --device-path 8be4df61-93ca-11d2-aa0d-00e098032b8c-ConOut
tell you? (Or run as root if you don't like sudo).

The boot loader grew a non-optional graphics mode that's disabled when the
boot code
detects we're talking to a 'serial port' between 12.x and 13.x. If you are
getting no output
from the loader at all, I suspect this is likely to blame.

> But the same works in FreeBSD 12.3 and Putty gets the output from EFI
> loader for both x86 and arm64.
>
> But during kernel booting the console output does not come in Putty, it
> only comes in vmconnect.exe.
>

So on 12.3, kernel output doesn't come out of both? Do you have
boot_multicons=YES in your loader.conf?
If not, only one of the consoles will get output from the kernel.

Warner

> Like below :
>
>
>
> Loading kernel...
>
> /boot/kernel/kernel text=0x931f24 data=0x187450 data=0x0+0x2d095e
> syms=[0x8+0x138120+0x8+0x124824]
>
> Loading configured modules...
>
> can't find '/boot/entropy'
>
> can't find '/etc/hostid'
>
> No valid device tree blob found!
>
> WARNING! Trying to fire up the kernel, but no device tree blob found!
>
> EFI framebuffer information:
>
> addr, size     0xe0000000, 0x800000
>
> dimensions     1024 x 768
>
> stride         1024
>
> masks          0x00ff0000, 0x0000ff00, 0x000000ff, 0xff000000 <<<<
>
>
>
> After this log is not coming in Putty in 12.3 for both x86 and arm64.
>
>
>
>
>
>
>