* Fix DevicesSets being removed when cpusets are reloaded with cgroup v2
This meant that if any allocation was created or removed, all
active DevicesSets were removed from all cgroups of all tasks.
This was most noticeable with "exec" and "raw_exec", as it meant
they no longer had access to /dev files.
* e2e: add test for verifying cgroups do not interfere with access to devices
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Co-authored-by: Seth Hoenig <shoenig@duck.com>
