Serial ports in Qubes appvms

[dono...@unseen.is]

I'd like to use serial console (via a serial port on the mobo and appropriate cable) into a piece of equipment using an appVM. I tried using dmesg, but dom0 term says "operation not permitted".

DM

[awokd]

dono...@unseen.is:

> I'd like to use serial console (via a serial port on the mobo and appropriate cable) into a piece of equipment using an appVM. I tried using dmesg, but dom0 term says "operation not permitted".
>
> DM
>

Don't believe Xen/Qubes supports serial (or parallel) port redirection.
Options would be to use some basic package in dom0 directly on the
serial port, get a PCI card with serial ports on it and redirect the
card to the AppVM, or a USB to serial adapter and redirect that.

Not sure how you're trying to use dmesg, but you probably have to sudo
to use a /dev/tty serial device directly in dom0.

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[dono...@unseen.is]

> --
It might not support redirection and for now I can live with that. However, I keep forgetting about having to use sudo, and using "sudo dmesg | grep ttyS" got me a listing of some serial ports. And agetty is in dom0, and that will suffice for now I think. I'm not talking to the device yet, but I'm further along in terms of knowledge.

Thank you.

DM

[Sven Semmler]

On Fri, Mar 06, 2020 at 10:12:07PM +0000, dono...@unseen.is wrote:
> I'd like to use serial console (via a serial port on the mobo and appropriate cable) into a piece of equipment using an appVM. I tried using dmesg, but dom0 term says "operation not permitted".

I'm doing this all the time using USB-to-serial-cables and minicom
instances in a Standalone HVM.

It would probably work just by assigning that USB device to a regular AppVM,
but since I also have other devices connected (ICE, I2C/SPI logger,
logic analyzer) I just assign the entire USB controller to the HVM.

If your serial port controller shows up with qvm-pci you could also try
to assign that one the the VM.

/Sven

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