Comment 18 for bug 1932165

Confirmed that lttng-modules-dkms 2.12.5-1ubuntu2~21.04.1 in hirsute-proposed can be installed, build and loaded successfully:

$ dkms status
lttng-modules, 2.12.5, 5.11.0-33-generic, x86_64: installed

$ lsmod | grep "^lttng" | awk '{ print $1 }'
lttng_test
lttng_ring_buffer_metadata_mmap_client
lttng_ring_buffer_metadata_client
lttng_ring_buffer_client_overwrite
lttng_ring_buffer_client_mmap_overwrite
lttng_ring_buffer_client_mmap_discard
lttng_ring_buffer_client_discard
lttng_probe_writeback
lttng_probe_workqueue
lttng_probe_vmscan
lttng_probe_v4l2
lttng_probe_udp
lttng_probe_timer
lttng_probe_sunrpc
lttng_probe_statedump
lttng_probe_sock
lttng_probe_skb
lttng_probe_signal
lttng_probe_scsi
lttng_probe_sched
lttng_probe_regulator
lttng_probe_rcu
lttng_probe_random
lttng_probe_printk
lttng_probe_power
lttng_probe_net
lttng_probe_napi
lttng_probe_module
lttng_probe_kvm
lttng_probe_kmem
lttng_probe_jbd2
lttng_probe_irq
lttng_probe_gpio
lttng_probe_compaction
lttng_probe_block
lttng_probe_asoc
lttng_probe_9p
lttng_tracer
lttng_statedump
lttng_wrapper
lttng_uprobes
lttng_lib_ring_buffer
lttng_kretprobes
lttng_kprobes
lttng_clock_plugin_test
lttng_clock

autopkgtest also completed successfully:

amd64 - https://autopkgtest.ubuntu.com/results/autopkgtest-hirsute/hirsute/amd64/l/lttng-modules/20210827_092600_f29e1@/log.gz
arm64 - https://autopkgtest.ubuntu.com/results/autopkgtest-hirsute/hirsute/arm64/l/lttng-modules/20210827_093210_e3a3a@/log.gz
admhf - not supported
ppc64el - https://autopkgtest.ubuntu.com/results/autopkgtest-hirsute/hirsute/ppc64el/l/lttng-modules/20210827_092927_f29e1@/log.gz
s390x - https://autopkgtest.ubuntu.com/results/autopkgtest-hirsute/hirsute/s390x/l/lttng-modules/20210827_091858_e3a3a@/log.gz

Thanks!