Re: [libvirt] [PATCH v2 1/2] conf: add debugcon chardev guest interface

On Mon, 2019-02-11 at 08:14 +0000, Nikolay Shirokovskiy wrote: > On 08.02.2019 17:34, Andrea Bolognani wrote: >> Even with that fixed, while your code prevents a <console> element >> associated to the isa-debugcon to be automatically created, it >> doesn't prevent something like >> >> <console type='pty'/> >> <serial type='file'> >> <source path='...'/> >> <target type='isa-serial'> >> <model name='isa-debugcon'/> >> </target> >> </serial> >> >> to result in the same problematic configuration, while the user >> clearly wanted to have both a regular serial console *and* the >> isa-debugcon. > > Yeah I noticed that too but I though this is like case of usb-serial > for example. We do not add missing console in that case but allow > existing console to be alias of usb-serial. Hm, that looks like a bug. I think we should be consistent about this: either the aliasing between <serial/> and <console/> works both ways, or it should not happen at all IMHO. > Can usb-serial actually be console? No idea :) >>> + <serial type='pipe'> >>> + <source path='/tmp/debugcon'/> >>> + <target type='isa-serial' port='0'> >>> + <model name='isa-debugcon'/> >>> + </target> >>> + <address type='isa' iobase='0x402'/> >>> + </serial> >> >> So IIUC iobase=0x402 is the de-facto standard for isa-debugcon, >> right? >> >> Assuming that's indeed the case, I would expect libvirt to fill in >> that value automatically unless the user has provided an iobase >> explicitly themselves. > > I wonder then why qemu uses a different value - 0xe9? If that's the default value for isa-debugcon.iobase as far as QEMU is concerned, then we should use that value in libvirt too. But I thought you said 0x402 was the default?