Re: QGA installation issue on Windows

["Michal Prívozník" <mprivozn@redhat.com>]

On 8/4/25 13:01, Daniel P. Berrangé wrote:
> On Mon, Aug 04, 2025 at 01:54:09PM +0300, Kostiantyn Kostiuk wrote:
>> Hi Michal,
>>
>> I want to discuss your patch
>> https://gitlab.com/qemu-project/qemu/-/commit/c6f5dd7ac8ef62dcdec4cdeda1467c658161afff
>>
>> Unfortunately, we found bad behaviour on Windows. On Windows, we run QGA
>> with `-d --retry-path` options by default, so we expect that QGA will start
>> even without the vioserial driver and will wait for communication
>> forever.
>>
>> This worked previously, but after your patch QGA service fails if the
>> vioserial communication channel is missing. This behavior is totally
>> unacceptable for us.
>>
>> You send this patch to fix a Linux problem, but it causes a Windows problem.
>> So, what we need on Windows, if --retry-path specified, we should ignore
>> any channel error and retry the connection. If -d and --retry-path are
>> specified, it should become a daemon first to make Windows Service Manager
>> happy.

The original problem I tried to fix was (and I am bit hazy on all the
details): when somebody built their own kernel but forgot to enable
virtio-serial then qemu-ga would fail to initialize but with a
completely irrelevant error message.

> 
> This looks pretty simple to fix - in the initialize_agent() method, if
> channel_init() fails, then simply ignore the failure if 'retry_path'
> is set, because the later code in run_agent() will already correctly
> retry the connection.

Yeah, do you want me to post such patch?

Michal