Comment 0 for bug 1959424

d2021.10.26/jammy/linux-realtime/5.15.0-1004.4, only on node appleton-kernel.arm64, hangs on ubuntu_kernel_selftests / ftrace:ftracetest test:
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01:28:34 DEBUG| [stdout] # === Ftrace unit tests ===
01:28:34 DEBUG| [stdout] # [1] Basic trace file check [PASS]
01:28:38 DEBUG| [stdout] # [2] Basic test for tracers [PASS]
01:28:38 DEBUG| [stdout] # [3] Basic trace clock test [PASS]
01:28:38 DEBUG| [stdout] # [4] Basic event tracing check [PASS]
01:28:39 DEBUG| [stdout] # [5] Change the ringbuffer size [PASS]
01:28:39 DEBUG| [stdout] # [6] Snapshot and tracing setting [PASS]
01:28:40 DEBUG| [stdout] # [7] trace_pipe and trace_marker [PASS]
01:28:40 DEBUG| [stdout] # [8] Test ftrace direct functions against tracers [UNRESOLVED]
01:28:40 DEBUG| [stdout] # [9] Test ftrace direct functions against kprobes [UNRESOLVED]
01:28:40 DEBUG| [stdout] # [10] Generic dynamic event - add/remove eprobe events [PASS]
01:28:41 DEBUG| [stdout] # [11] Generic dynamic event - add/remove kprobe events [PASS]
01:28:41 DEBUG| [stdout] # [12] Generic dynamic event - add/remove synthetic events [PASS]
01:28:41 DEBUG| [stdout] # [13] Generic dynamic event - selective clear (compatibility) [PASS]
01:28:41 DEBUG| [stdout] # [14] Generic dynamic event - generic clear event [PASS]
01:28:42 DEBUG| [stdout] # [15] Generic dynamic event - check if duplicate events are caught [PASS]
01:58:36 INFO | Timer expired (1800 sec.), nuking pid 161336
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The issue was not reproduced on mcdivitt36 (HP ProLiant m400 server cartridge with AppliedMicro X-Gene 64-bit ARM).