Hello, Recently I''ve been trying to setup domain which can use serial port (modem communication). First I had to struggle to setup working serial in domain 0 - besides "console=vga" parameter in grub I had to add fake com port parameters to prevent xen from stealing ttyS0 on default I/O&IRQ. Furthermore, parameter "xencons=off" must be passed to linux kernel, and then serial port in domain 0 works - I can "modprobe 8250", "setserial /dev/ttyS0 uart 16550A", "echo ATA > /dev/ttyS0" without problem. I compiled kernel to use in another domain - I used CONFIG_XEN_PRIVILEGED_GUEST=y and CONFIG_XEN_PHYSDEV_ACCESS=y, switched off PCI/ISA buses and all drivers except serial port. This kernel boots successfully in virtual machine and even serial driver pretends to load but fails to work - "setserial /dev/ttyS0 uart 16550A" triggers kernel message "ttyS0: LSR safety check engaged!". This happens of course when serial is not used (8250 module not loaded) in dom0. Am i missing something? (I am using testing xen-3-devel 2005-07-26) Regards, Michal _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
I don''t think there''s a way to dedicate serial ports to domains. It shouldn''t be technically hard but nobody has wanted to do it before. We''d take a patch to enable it but in the absence of that I''m afraid you''ll have to work around this issue - most simple is probably to control the modem from dom0 and then allow the domU to access the resulting network connection. Cheers, Mark On Wednesday 27 July 2005 12:57, mikee wrote:> Hello, > Recently I''ve been trying to setup domain which can use > serial port (modem communication). First I had to struggle > to setup working serial in domain 0 - besides "console=vga" > parameter in grub I had to add fake com port parameters > to prevent xen from stealing ttyS0 on default I/O&IRQ. > Furthermore, parameter "xencons=off" must be passed to linux > kernel, and then serial port in domain 0 works - I can > "modprobe 8250", "setserial /dev/ttyS0 uart 16550A", > "echo ATA > /dev/ttyS0" without problem. I compiled kernel > to use in another domain - I used CONFIG_XEN_PRIVILEGED_GUEST=y > and CONFIG_XEN_PHYSDEV_ACCESS=y, switched off PCI/ISA buses and > all drivers except serial port. This kernel boots successfully > in virtual machine and even serial driver pretends to load > but fails to work - "setserial /dev/ttyS0 uart 16550A" triggers > kernel message "ttyS0: LSR safety check engaged!". This happens > of course when serial is not used (8250 module not loaded) > in dom0. Am i missing something? > (I am using testing xen-3-devel 2005-07-26) > > Regards, > Michal > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
2005-07-27, sze keltezéssel 13.43-kor Mark Williamson ezt írta:> I don''t think there''s a way to dedicate serial ports to domains. It shouldn''t > be technically hard but nobody has wanted to do it before. We''d take a patch > to enable it but in the absence of that I''m afraid you''ll have to work around > this issue - most simple is probably to control the modem from dom0 and then > allow the domU to access the resulting network connection.What about using an USB serial port? Regards, Slapic _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users