[PATCH] tools/hotplug: xendomains.service conflicts with libvirt

[PATCH] tools/hotplug: xendomains.service conflicts with libvirt

[Olaf Hering]

xendomains will manage guests behind libvirts back:
- libvirt starts a guest
- that guest can be "managed" by libvirt and xl at the same time
- when xendomains runs on shutdown it will save the guest using xl
  libvirt does not know about this
- when xendomains runs on boot it will restore the saved guest using xl
  libvirt does not know about this, it will just fail to manage the
  restored guest

To prevent xendomains from interfering with libvirt add a Conflicts= to
xendomains.service. It will cause libvirt to be stopped if xendomains is
started manually with 'systemctl start'

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
---

This never went out via git send-email, sorry about this.


 tools/hotplug/Linux/systemd/xendomains.service.in | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/hotplug/Linux/systemd/xendomains.service.in b/tools/hotplug/Linux/systemd/xendomains.service.in
index 66e2065..3875de1 100644
--- a/tools/hotplug/Linux/systemd/xendomains.service.in
+++ b/tools/hotplug/Linux/systemd/xendomains.service.in
@@ -4,6 +4,7 @@ Requires=proc-xen.mount xenstored.service
 After=proc-xen.mount xenstored.service xenconsoled.service xen-init-dom0.service
 After=network-online.target
 After=remote-fs.target
+Conflicts=libvirt.service
 ConditionPathExists=/proc/xen/capabilities
 
 [Service]

Re: [PATCH] tools/hotplug: xendomains.service conflicts with libvirt

[Wei Liu]

On Thu, Oct 29, 2015 at 10:22:45AM +0000, Olaf Hering wrote:
> xendomains will manage guests behind libvirts back:
> - libvirt starts a guest
> - that guest can be "managed" by libvirt and xl at the same time
> - when xendomains runs on shutdown it will save the guest using xl
>   libvirt does not know about this
> - when xendomains runs on boot it will restore the saved guest using xl
>   libvirt does not know about this, it will just fail to manage the
>   restored guest
> 
> To prevent xendomains from interfering with libvirt add a Conflicts= to
> xendomains.service. It will cause libvirt to be stopped if xendomains is
> started manually with 'systemctl start'
> 
> Signed-off-by: Olaf Hering <olaf@aepfle.de>
> Cc: Ian Jackson <ian.jackson@eu.citrix.com>
> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> Cc: Ian Campbell <ian.campbell@citrix.com>
> Cc: Wei Liu <wei.liu2@citrix.com>
> ---
> 
> This never went out via git send-email, sorry about this.
> 
> 
>  tools/hotplug/Linux/systemd/xendomains.service.in | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/tools/hotplug/Linux/systemd/xendomains.service.in b/tools/hotplug/Linux/systemd/xendomains.service.in
> index 66e2065..3875de1 100644
> --- a/tools/hotplug/Linux/systemd/xendomains.service.in
> +++ b/tools/hotplug/Linux/systemd/xendomains.service.in
> @@ -4,6 +4,7 @@ Requires=proc-xen.mount xenstored.service
>  After=proc-xen.mount xenstored.service xenconsoled.service xen-init-dom0.service
>  After=network-online.target
>  After=remote-fs.target
> +Conflicts=libvirt.service

Is there a canonical source for the name of service? We should reference
that in commit message.

My quick search on the Internet presents libvirtd.service as well. I
fear the name of the service is up to distros, which means we shouldn't
put one in xendomains.service.

Wei.

>  ConditionPathExists=/proc/xen/capabilities
>  
>  [Service]

Re: [PATCH] tools/hotplug: xendomains.service conflicts with libvirt

[Olaf Hering]

On Thu, Oct 29, Wei Liu wrote:

> On Thu, Oct 29, 2015 at 10:22:45AM +0000, Olaf Hering wrote:
> > +Conflicts=libvirt.service
> Is there a canonical source for the name of service? We should reference
> that in commit message.

No, its a typo. Thanks for spotting it.

The change which went into the xen package a few months ago uses
libvirtd.service, which is also the name in libvirt.git. Just the
variant of the change in my local copy of xen.git has the typo.

I just sent v2 of the change.

Olaf

Re: [PATCH] tools/hotplug: xendomains.service conflicts with libvirt

[Andrew Cooper]

On 29/10/15 10:29, Wei Liu wrote:
> On Thu, Oct 29, 2015 at 10:22:45AM +0000, Olaf Hering wrote:
>> xendomains will manage guests behind libvirts back:
>> - libvirt starts a guest
>> - that guest can be "managed" by libvirt and xl at the same time
>> - when xendomains runs on shutdown it will save the guest using xl
>>   libvirt does not know about this
>> - when xendomains runs on boot it will restore the saved guest using xl
>>   libvirt does not know about this, it will just fail to manage the
>>   restored guest
>>
>> To prevent xendomains from interfering with libvirt add a Conflicts= to
>> xendomains.service. It will cause libvirt to be stopped if xendomains is
>> started manually with 'systemctl start'
>>
>> Signed-off-by: Olaf Hering <olaf@aepfle.de>
>> Cc: Ian Jackson <ian.jackson@eu.citrix.com>
>> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
>> Cc: Ian Campbell <ian.campbell@citrix.com>
>> Cc: Wei Liu <wei.liu2@citrix.com>
>> ---
>>
>> This never went out via git send-email, sorry about this.
>>
>>
>>  tools/hotplug/Linux/systemd/xendomains.service.in | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/tools/hotplug/Linux/systemd/xendomains.service.in b/tools/hotplug/Linux/systemd/xendomains.service.in
>> index 66e2065..3875de1 100644
>> --- a/tools/hotplug/Linux/systemd/xendomains.service.in
>> +++ b/tools/hotplug/Linux/systemd/xendomains.service.in
>> @@ -4,6 +4,7 @@ Requires=proc-xen.mount xenstored.service
>>  After=proc-xen.mount xenstored.service xenconsoled.service xen-init-dom0.service
>>  After=network-online.target
>>  After=remote-fs.target
>> +Conflicts=libvirt.service
> Is there a canonical source for the name of service? We should reference
> that in commit message.
>
> My quick search on the Internet presents libvirtd.service as well. I
> fear the name of the service is up to distros, which means we shouldn't
> put one in xendomains.service.

If it is a service file provided by libvirt upstream, we can probably
get away with naming it explicitly.

If each distro write their own service files for libvirt, we probably can't.

~Andrew

Re: [PATCH] tools/hotplug: xendomains.service conflicts with libvirt

[Wei Liu]

On Thu, Oct 29, 2015 at 11:07:22AM +0000, Andrew Cooper wrote:
> On 29/10/15 10:29, Wei Liu wrote:
> > On Thu, Oct 29, 2015 at 10:22:45AM +0000, Olaf Hering wrote:
> >> xendomains will manage guests behind libvirts back:
> >> - libvirt starts a guest
> >> - that guest can be "managed" by libvirt and xl at the same time
> >> - when xendomains runs on shutdown it will save the guest using xl
> >>   libvirt does not know about this
> >> - when xendomains runs on boot it will restore the saved guest using xl
> >>   libvirt does not know about this, it will just fail to manage the
> >>   restored guest
> >>
> >> To prevent xendomains from interfering with libvirt add a Conflicts= to
> >> xendomains.service. It will cause libvirt to be stopped if xendomains is
> >> started manually with 'systemctl start'
> >>
> >> Signed-off-by: Olaf Hering <olaf@aepfle.de>
> >> Cc: Ian Jackson <ian.jackson@eu.citrix.com>
> >> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> >> Cc: Ian Campbell <ian.campbell@citrix.com>
> >> Cc: Wei Liu <wei.liu2@citrix.com>
> >> ---
> >>
> >> This never went out via git send-email, sorry about this.
> >>
> >>
> >>  tools/hotplug/Linux/systemd/xendomains.service.in | 1 +
> >>  1 file changed, 1 insertion(+)
> >>
> >> diff --git a/tools/hotplug/Linux/systemd/xendomains.service.in b/tools/hotplug/Linux/systemd/xendomains.service.in
> >> index 66e2065..3875de1 100644
> >> --- a/tools/hotplug/Linux/systemd/xendomains.service.in
> >> +++ b/tools/hotplug/Linux/systemd/xendomains.service.in
> >> @@ -4,6 +4,7 @@ Requires=proc-xen.mount xenstored.service
> >>  After=proc-xen.mount xenstored.service xenconsoled.service xen-init-dom0.service
> >>  After=network-online.target
> >>  After=remote-fs.target
> >> +Conflicts=libvirt.service
> > Is there a canonical source for the name of service? We should reference
> > that in commit message.
> >
> > My quick search on the Internet presents libvirtd.service as well. I
> > fear the name of the service is up to distros, which means we shouldn't
> > put one in xendomains.service.
> 
> If it is a service file provided by libvirt upstream, we can probably
> get away with naming it explicitly.
> 

Yes, that's also considered a "canonical source". :-)

> If each distro write their own service files for libvirt, we probably can't.
> 
> ~Andrew