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.
-- 
Sincerely,
Demi Marie Obenour (she/her/hers)