Re: [Xen-devel] [PATCH for-xen-4.5] tools/hotplug: fix systemd service files for dom0

[Anthony PERARD <anthony.perard@xxxxxxxxxx>]

On Wed, Oct 15, 2014 at 11:11:58AM +0200, Olaf Hering wrote:
> ConditionVirtualization= checks if systemd runs in some sort of guest.
> It is not supposed to detect host capabilities. The current
> implementation happens to work because systemd-detect-virt from v208
> returns also 'xen' in a dom0. In v210 and later 'none' is returned and
> all service files are not started.
> 
> Adjust the checks to detect a dom0 vs. native boot. Mounting xenfs
> depends on /proc/xen, but should only be done for pvops because xenfs
> exists only there. All other service files should not be started in
> domU. The file /proc/xen/capabilities exists in both dom0 and domU in a
> pvops kernel, but only in dom0 it contains 'control_d'. The existing
> ExecStartPre= check will prevent starting in a domU.
> 
> ConditionVirtualization=!xen is true in a dom0. But this check is broken
> in systemd v208, so its not used.
> 
> Signed-off-by: Olaf Hering <olaf@xxxxxxxxx>
> Cc: Ian Campbell <ian.campbell@xxxxxxxxxx>
> Cc: Ian Jackson <ian.jackson@xxxxxxxxxxxxx>
> Cc: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
> Cc: Wei Liu <wei.liu2@xxxxxxxxxx>
> ---
> 
> I'm having a hard time to get a pvops dom0, so this is only tested with SUSE 
> dom0.

I've tested this patch in both dom0 and bare metal (with Linux 3.17.1
and systemd v216) and it mostly works, only one unit does not work,
var-lib-xenstored.mount.

(for some reason, ConditionVirtualization=xen, is still true on dom0
with systemd v216, even so systemd-detect-virt is returning 'none' ...)

>  tools/hotplug/Linux/systemd/proc-xen.mount.in                     | 3 ++-
>  tools/hotplug/Linux/systemd/var-lib-xenstored.mount.in            | 2 +-
>  tools/hotplug/Linux/systemd/xen-qemu-dom0-disk-backend.service.in | 2 +-
>  tools/hotplug/Linux/systemd/xen-watchdog.service.in               | 2 +-
>  tools/hotplug/Linux/systemd/xenconsoled.service.in                | 2 +-
>  tools/hotplug/Linux/systemd/xendomains.service.in                 | 2 +-
>  tools/hotplug/Linux/systemd/xenstored.service.in                  | 2 +-
>  tools/hotplug/Linux/systemd/xenstored.socket.in                   | 2 +-
>  tools/hotplug/Linux/systemd/xenstored_ro.socket.in                | 2 +-
>  9 files changed, 10 insertions(+), 9 deletions(-)
> 
> diff --git a/tools/hotplug/Linux/systemd/proc-xen.mount.in 
> b/tools/hotplug/Linux/systemd/proc-xen.mount.in
> index f0c4f3a..64ebe7f 100644
> --- a/tools/hotplug/Linux/systemd/proc-xen.mount.in
> +++ b/tools/hotplug/Linux/systemd/proc-xen.mount.in
> @@ -1,6 +1,7 @@
>  [Unit]
>  Description=Mount /proc/xen files
> -ConditionVirtualization=xen
> +ConditionPathExists=/proc/xen
> +ConditionPathExists=!/proc/xen/capabilities
>  RefuseManualStop=true
>  
>  [Mount]
> diff --git a/tools/hotplug/Linux/systemd/var-lib-xenstored.mount.in 
> b/tools/hotplug/Linux/systemd/var-lib-xenstored.mount.in
> index 1e930ed..64b560f 100644
> --- a/tools/hotplug/Linux/systemd/var-lib-xenstored.mount.in
> +++ b/tools/hotplug/Linux/systemd/var-lib-xenstored.mount.in
> @@ -1,6 +1,6 @@
>  [Unit]
>  Description=mount xenstore file system
> -ConditionVirtualization=xen
> +ConditionPathExists=/proc/xen/capabilities

On my systemd, var/lib/xenstored is not mounted because
ConditionPathExists=/proc/xen/capabilities was not met
even so proc-xen.mount is mounted.

So there is probably a dependency missing on proc-xen.mount.

>  RefuseManualStop=true
>  
>  [Mount]

-- 
Anthony PERARD

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel