Demi Marie Obenour <demiobenour@gmail.com> writes:

> On 7/29/26 10:15, Alyssa Ross wrote:
>> Demi Marie Obenour <demiobenour@gmail.com> writes:
>> 
>>> On 7/27/26 08:20, Alyssa Ross wrote:
>>>> Demi Marie Obenour <demiobenour@gmail.com> writes:
>>>>
>>>>> Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
>>>>> ---
>>>>>  host/rootfs/file-list.mk                         | 1 +
>>>>>  host/rootfs/image/etc/s6-rc/systemd-udevd/finish | 5 +++++
>>>>>  host/rootfs/image/etc/s6-rc/systemd-udevd/run    | 5 +++--
>>>>>  3 files changed, 9 insertions(+), 2 deletions(-)
>>>>>
>>>>> diff --git a/host/rootfs/file-list.mk b/host/rootfs/file-list.mk
>>>>> index e3411d40014342e67071a48f9e1c7bc7b3954bcf..065571ef3a5c61fa79a1d2ed878052a5f391be96 100644
>>>>> --- a/host/rootfs/file-list.mk
>>>>> +++ b/host/rootfs/file-list.mk
>>>>> @@ -106,6 +106,7 @@ S6_RC_FILES = \
>>>>>  	image/etc/s6-rc/systemd-udevd-coldplug/dependencies.d/systemd-udevd \
>>>>>  	image/etc/s6-rc/systemd-udevd-coldplug/type \
>>>>>  	image/etc/s6-rc/systemd-udevd-coldplug/up \
>>>>> +	image/etc/s6-rc/systemd-udevd/finish \
>>>>>  	image/etc/s6-rc/systemd-udevd/notification-fd \
>>>>>  	image/etc/s6-rc/systemd-udevd/run \
>>>>>  	image/etc/s6-rc/systemd-udevd/type \
>>>>> diff --git a/host/rootfs/image/etc/s6-rc/systemd-udevd/finish b/host/rootfs/image/etc/s6-rc/systemd-udevd/finish
>>>>> new file mode 100755
>>>>> index 0000000000000000000000000000000000000000..4d5b454e97c3584d0644c2d738514f13b1c53957
>>>>> --- /dev/null
>>>>> +++ b/host/rootfs/image/etc/s6-rc/systemd-udevd/finish
>>>>> @@ -0,0 +1,5 @@
>>>>> +#!/usr/bin/execlineb -WS3
>>>>> +# SPDX-License-Identifier: EUPL-1.2+
>>>>> +# SPDX-FileCopyrightText: 2026 Demi Marie Obenour <demiobenour@gmail.com>
>>>>> +
>>>>> +cgroup-s6-finish $@
>>>>> diff --git a/host/rootfs/image/etc/s6-rc/systemd-udevd/run b/host/rootfs/image/etc/s6-rc/systemd-udevd/run
>>>>> old mode 100644
>>>>> new mode 100755
>>>>> index aec6444e951503eae988e666b77fda8f2ae33d72..901f3e6667a8de04a6af39945406a1757455f089
>>>>> --- a/host/rootfs/image/etc/s6-rc/systemd-udevd/run
>>>>> +++ b/host/rootfs/image/etc/s6-rc/systemd-udevd/run
>>>>> @@ -1,7 +1,8 @@
>>>>> -#!/bin/execlineb -WP
>>>>> +#!/bin/execlineb -WS1
>>>>>  # SPDX-License-Identifier: EUPL-1.2+
>>>>>  # SPDX-FileCopyrightText: 2025 Demi Marie Obenour <demiobenour@gmail.com>
>>>>> -s6-setlock /run/sd-notify-wrapper/systemd-udevd.lock
>>>>> +
>>>>> +cgroup-setup --delegate --child-name udev -- $1
>>>>>  s6-ipcserver-socketbinder -b0 -m -a 0600 /run/sd-notify-wrapper/systemd-udevd.sock
>>>>>  background -d {
>>>>>     fdmove 1 3
>>>>>
>>>>
>>>> Is there a reason not to always enable delegation?  Is there a reason we
>>>> need to set the name here?
>>>
>>> --delegate only sets the user.delegate=1 xattr used by systemd.
>>> Programs that are systemd-aware and manage their own cgroups check this
>>> xattr to see if a cgroup has been delegated by systemd.  The kernel
>>> and other programs do not care.
>> 
>> Right, but why can't we just always set user.delegate=1?  Would we ever
>> have a program that checked it that we didn't want to manage its own
>> cgroups?
>
> It's slightly wasteful (extra syscall) but harmless.
>
>>> systemd-udevd.service uses the "udev" name, so I decided to also use it
>>> for consistency.
>> 
>> Is this the only reason we even need a --child-name feature?  If so, it
>> doesn't seem well justified to me unless it actually affects something.
>
> I'd prefer to stick with what systemd uses, as that is what is tested.
> Varying from what systemd uses increases the risk of regressions.

I'd be very surprised if the name of the cgroup is a practical
regression risk.  I don't think it justifies extra complexity in
cgroup-setup.