RPCS3's AppImage could not start: its own runtime unpacks the image with
a dwarfsextract it runs from a memfd, which Android refuses (EACCES), and
it has no other way to run it. Emulator AppImages for arm64 now start
through the shipped uruntime, which falls back to a file in /tmp.
RPCS3 then stopped with "Null object" in utils::shm (errno 13): it reads
/proc/sys/vm/overcommit_memory to pick memfd for guest memory, and apps
cannot read it. The guest now gets the kernel's default policy (0) there
when the real file is unreadable, like file-max.
