[RFC PATCH libvirt v1 2/3] Improve `virsh start --console` behavior

[Marc Hartmayer]

On Mon, Sep 25, 2023 at 04:15 PM +0100, Daniel P. Berrangé <berrange at redhat.com> wrote:
> On Mon, Sep 25, 2023 at 03:39:09PM +0200, Marc Hartmayer wrote:
>> When starting a guest via libvirt (`virsh start --console`), early
>> console output was missed because the guest was started first and then
>> the console was attached. This patch changes this to the following
>> sequence:
>> 
>> 1. create a paused guest
>> 2. attach the console
>> 3. resume the guest
>> 
>> Reviewed-by: Boris Fiuczynski <fiuczy at linux.ibm.com>
>> Signed-off-by: Marc Hartmayer <mhartmay at linux.ibm.com>
>> ---
>>  tools/virsh-domain.c | 11 +++++++++--
>>  1 file changed, 9 insertions(+), 2 deletions(-)
>> 
>> diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
>> index 5c3c6d18aebf..3581161c6f53 100644
>> --- a/tools/virsh-domain.c
>> +++ b/tools/virsh-domain.c
>> @@ -4065,6 +4065,7 @@ cmdStart(vshControl *ctl, const vshCmd *cmd)
>>      g_autoptr(virshDomain) dom = NULL;
>>  #ifndef WIN32
>>      bool console = vshCommandOptBool(cmd, "console");
>> +    bool resume_domain = false;
>>  #endif
>>      unsigned int flags = VIR_DOMAIN_NONE;
>>      int rc;
>> @@ -4083,8 +4084,14 @@ cmdStart(vshControl *ctl, const vshCmd *cmd)
>>      if (virshFetchPassFdsList(ctl, cmd, &nfds, &fds) < 0)
>>          return false;
>>  
>> -    if (vshCommandOptBool(cmd, "paused"))
>> +    if (vshCommandOptBool(cmd, "paused")) {
>>          flags |= VIR_DOMAIN_START_PAUSED;
>> +#ifndef WIN32
>> +    } else if (console) {
>> +        flags |= VIR_DOMAIN_START_PAUSED;
>> +        resume_domain = true;
>> +#endif
>
> Hypervisor drivers are not required to support VIR_DOMAIN_START_PAUSED.
>
> So we need to detect the error code, and retry without that flag
> set as a fallback. Same in next patch.

Yep, makes sense - will change. Thanks for the feedback.

[…snip]

-- 
Kind regards / Beste Grüße
   Marc Hartmayer

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