Problems with serial passthrough

[wrt54gl]

I have A windows 7 guest running on proxmox 1.9. The guest runs some software to link to some industrial control via rs485. Normally we run this with a serial port and a rs232 to rs485 adapter and it works fine on windows 7. After building a win7 guest and putting: "serial: /dev/ttyS3" in the conf file the serial port seems to work to poll devices and read values most of the time but does not seem to be able to write values to the devices. I have done a lot of googleing on this and cannot seem to find any solutions or any way to go about trouble shooting this.

Any help is appreciated.

 

[dietmar]

Does that work with earlier versions (V1.8)?

 

[wrt54gl]

No it didn't work with 1.8 either.

 

[ajit]

it has to do with kernel versions, i have 3 machines and i keep one of them with the older kernel version and it works fine, not near the machines else i would post the versions. when the initial fork happened for only kvm is when this started.

 

[wrt54gl]

Have you been able to find out which kernel versions this will work with. Alternately I could try pci pass through again although I did try it a bit with 1.8 and had a couple of occasions where the guest became unresponsive to the point that I had to reboot the proxmox host. Maybe 1.9 will have fixed some of these issues?