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# zygote-start is what officially starts netd (see //system/core/rootdir/init.rc)
# However, on some hardware it's started from post-fs-data as well, which is just
# a tad earlier. There's no benefit to that though, since on 4.9+ P+ devices netd
# will just block until bpfloader finishes and sets the bpf.progs_loaded property.
#
# It is important that we start bpfloader after:
# - /sys/fs/bpf is already mounted,
# - apex (incl. rollback) is initialized (so that in the future we can load bpf
# programs shipped as part of apex mainline modules)
# - logd is ready for us to log stuff
#
# At the same time we want to be as early as possible to reduce races and thus
# failures (before memory is fragmented, and cpu is busy running tons of other
# stuff) and we absolutely want to be before netd and the system boot slot is
# considered to have booted successfully.
#
on load_bpf_programs
# Enable the eBPF JIT -- but do note that on 64-bit kernels it is likely
# already force enabled by the kernel config option BPF_JIT_ALWAYS_ON
write /proc/sys/net/core/bpf_jit_enable 1
# Enable JIT kallsyms export for privileged users only
write /proc/sys/net/core/bpf_jit_kallsyms 1
exec_start bpfloader
service bpfloader /system/bin/bpfloader
capabilities CHOWN SYS_ADMIN NET_ADMIN
#
# Set RLIMIT_MEMLOCK to 1GiB for bpfloader
#
# Actually only 8MiB would be needed if bpfloader ran as its own uid.
#
# However, while the rlimit is per-thread, the accounting is system wide.
# So, for example, if the graphics stack has already allocated 10MiB of
# memlock data before bpfloader even gets a chance to run, it would fail
# if its memlock rlimit is only 8MiB - since there would be none left for it.
#
# bpfloader succeeding is critical to system health, since a failure will
# cause netd crashloop and thus system server crashloop... and the only
# recovery is a full kernel reboot.
#
# We've had issues where devices would sometimes (rarely) boot into
# a crashloop because bpfloader would occasionally lose a boot time
# race against the graphics stack's boot time locked memory allocation.
#
# Thus bpfloader's memlock has to be 8MB higher then the locked memory
# consumption of the root uid anywhere else in the system...
# But we don't know what that is for all possible devices...
#
# Ideally, we'd simply grant bpfloader the IPC_LOCK capability and it
# would simply ignore it's memlock rlimit... but it turns that this
# capability is not even checked by the kernel's bpf system call.
#
# As such we simply use 1GiB as a reasonable approximation of infinity.
#
rlimit memlock 1073741824 1073741824
oneshot
reboot_on_failure reboot,bpfloader-failed
# we're not really updatable, but want to be able to load bpf programs shipped in apexes
updatable
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