ftrace in ubuntu_kernel_selftests failed with "check if duplicate events are caught" on P9

[Thibf]

Issue found on:
- Jammy 5.15.0-36.37 with Power9 baltar
- Kinetic 5.19.0-47.49 with Power9 baltar
- Lunar 6.2.0-25.25 with Power9 baltar

Test failed with:
# [15] Generic dynamic event - check if duplicate events are caught [FAIL]

Test Log:
 make: Entering directory '/home/ubuntu/autotest/client/tmp/ubuntu_kernel_selftests/src/linux/tools/testing/selftests/ftrace'
 TAP version 13
 1..1
 # selftests: ftrace: ftracetest
 # === Ftrace unit tests ===
 # [1] Basic trace file check [PASS]
 # [2] Basic test for tracers [PASS]
 # [3] Basic trace clock test [PASS]
 # [4] Basic event tracing check [PASS]
 # [5] Change the ringbuffer size [PASS]
 # [6] Snapshot and tracing setting [PASS]
 # [7] trace_pipe and trace_marker [PASS]
 # [8] Test ftrace direct functions against tracers [UNRESOLVED]
 # [9] Test ftrace direct functions against kprobes [UNRESOLVED]
 # [10] Generic dynamic event - add/remove eprobe events [PASS]
 # [11] Generic dynamic event - add/remove kprobe events [PASS]
 # [12] Generic dynamic event - add/remove synthetic events [PASS]
 # [13] Generic dynamic event - selective clear (compatibility) [PASS]
 # [14] Generic dynamic event - generic clear event [PASS]
 # [15] Generic dynamic event - check if duplicate events are caught [FAIL]
 # [16] event tracing - enable/disable with event level files [PASS]
 # [17] event tracing - restricts events based on pid notrace filtering [PASS]
 # [18] event tracing - restricts events based on pid [PASS]
 # [19] event tracing - enable/disable with subsystem level files [PASS]
 # [20] event tracing - enable/disable with top level files [PASS]
 # [21] Test trace_printk from module [PASS]
 # [22] ftrace - function graph filters with stack tracer [PASS]
 # [23] ftrace - function graph filters [PASS]
 # [24] ftrace - function pid notrace filters [PASS]
 # [25] ftrace - function pid filters [PASS]
 # [26] ftrace - stacktrace filter command [PASS]
 # [27] ftrace - function trace with cpumask [PASS]
 # [28] ftrace - test for function event triggers [PASS]
 # [29] ftrace - function trace on module [PASS]
 # [30] ftrace - function profiling [PASS]
 # [31] ftrace - function profiler with function tracing [PASS]
 # [32] ftrace - test reading of set_ftrace_filter [PASS]
 # [33] ftrace - test for function traceon/off triggers [PASS]
 # [34] ftrace - test tracing error log support [PASS]
 # [35] Test creation and deletion of trace instances while setting an event [PASS]
 # [36] Test creation and deletion of trace instances [PASS]
 # [37] Kprobe dynamic event - adding and removing [PASS]
 # [38] Kprobe dynamic event - busy event check [PASS]
 # [39] Kprobe dynamic event with arguments [PASS]
 # [40] Kprobe event with comm arguments [PASS]
 # [41] Kprobe event string type argument [PASS]
 # [42] Kprobe event symbol argument [PASS]
 # [43] Kprobe event argument syntax [PASS]
 # [44] Kprobes event arguments with types [PASS]
 # [45] Kprobe event user-memory access [UNSUPPORTED]
 # [46] Kprobe event auto/manual naming [PASS]
 # [47] Kprobe dynamic event with function tracer [PASS]
 # [48] Create/delete multiprobe on kprobe event [PASS]
 # [49] Kprobe event parser error log check [PASS]
 # [50] Kretprobe dynamic event with arguments [PASS]
 # [51] Kretprobe dynamic event with maxactive [PASS]
 # [52] Kretprobe %return suffix test [PASS]
 # [53] Register/unregister many kprobe events [PASS]
 # [54] Kprobe profile [PASS]
 # [55] Uprobe event parser error log check [PASS]
 # [56] test for the preemptirqsoff tracer [UNSUPPORTED]
 # [57] Meta-selftest: Checkbashisms [PASS]
 # [58] Test wakeup tracer [PASS]
 # [59] Test wakeup RT tracer [PASS]
 # [60] event trigger - test inter-event histogram trigger expected fail actions [XFAIL]
 # [61] event trigger - test field variable support [PASS]
 # [62] event trigger - test multiple actions on hist trigger [PASS]
 # [63] event trigger - test inter-event histogram trigger onchange action [PASS]
 # [64] event trigger - test inter-event histogram trigger onmatch action [PASS]
 # [65] event trigger - test inter-event histogram trigger onmatch-onmax action [PASS]
 # [66] event trigger - test inter-event histogram trigger onmax action [PASS]
 # [67] event trigger - test inter-event histogram trigger snapshot action [PASS]
 # [68] event trigger - test inter-event histogram trigger eprobe on synthetic event [PASS]
 # [69] event trigger - test inter-event histogram trigger trace action with dynamic string param [PASS]
 # [70] event trigger - test synthetic_events syntax parser [PASS]
 # [71] event trigger - test synthetic_events syntax parser errors [PASS]
 # [72] event trigger - test inter-event histogram trigger trace action [PASS]
 # [73] event trigger - test event enable/disable trigger [PASS]
 # [74] event trigger - test trigger filter [PASS]
 # [75] event trigger - test histogram modifiers [PASS]
 # [76] event trigger - test histogram parser errors [PASS]
 # [77] event trigger - test multiple histogram triggers [PASS]
 # [78] event trigger - test snapshot-trigger [PASS]
 # [79] event trigger - test stacktrace-trigger [PASS]
 # [80] trace_marker trigger - test snapshot trigger [PASS]
 # [81] trace_marker trigger - test histogram with synthetic event against kernel event [PASS]
 # [82] trace_marker trigger - test histogram with synthetic event [PASS]
 # [83] event trigger - test traceon/off trigger [PASS]
 # [84] (instance) Basic test for tracers [PASS]
 # [85] (instance) Basic trace clock test [PASS]
 # [86] (instance) Change the ringbuffer size [PASS]
 # [87] (instance) Snapshot and tracing setting [PASS]
 # [88] (instance) trace_pipe and trace_marker [PASS]
 # [89] (instance) event tracing - enable/disable with event level files [PASS]
 # [90] (instance) event tracing - restricts events based on pid notrace filtering [PASS]
 # [91] (instance) event tracing - restricts events based on pid [PASS]
 # [92] (instance) event tracing - enable/disable with subsystem level files [PASS]
 # [93] (instance) ftrace - function pid notrace filters [PASS]
 # [94] (instance) ftrace - function pid filters [PASS]
 # [95] (instance) ftrace - stacktrace filter command [PASS]
 # [96] (instance) ftrace - test for function event triggers [PASS]
 # [97] (instance) ftrace - test for function traceon/off triggers [PASS]
 # [98] (instance) event trigger - test event enable/disable trigger [PASS]
 # [99] (instance) event trigger - test trigger filter [PASS]
 # [100] (instance) event trigger - test histogram modifiers [PASS]
 # [101] (instance) event trigger - test multiple histogram triggers [PASS]
 # [102] (instance) trace_marker trigger - test snapshot trigger [PASS]
 #
 #
 # # of passed: 96
 # # of failed: 1
 # # of unresolved: 2
 # # of untested: 0
 # # of unsupported: 2
 # # of xfailed: 1
 # # of undefined(test bug): 0
 not ok 1 selftests: ftrace: ftracetest # exit=1

[Po-Hsu Lin (cypressyew)]

I can see this issue on P8 node "dryden" with F-hwe-5.15 (5.15.0-78.85~20.04.1)

# [15] Generic dynamic event - check if duplicate events are caught [FAIL]

[Po-Hsu Lin (cypressyew)]

By running the test directly with -vvv flag:

    ./ftracetest -vvv test.d/ftrace/func_event_triggers.tc

We can see this test is failing with:
+ . /home/ubuntu/autotest/client/tmp/ubuntu_kselftests_ftrace/src/linux/tools/testing/selftests/ftrace/test.d/dynevent/test_duplicates.tc
+ echo 0
+ HAVE_KPROBES=0
+ [ -f kprobe_events ]
+ HAVE_KPROBES=1
+ clear_dynamic_events
+ again=1
+ stop=1
+ [ 1 -eq 1 ]
+ stop=2
+ [ 2 -gt 10 ]
+ again=2
+ grep -v ^# dynamic_events
+ read line
+ [ 2 -eq 1 ]
+ echo e:egroup/eevent syscalls/sys_enter_openat file=+0($filename):ustring
+ echo e:egroup/eevent syscalls/sys_enter_openat file=+0($filename):ustring
./ftracetest: 21: echo: echo: I/O error
+ echo e:syscalls/sys_enter_open syscalls/sys_enter_openat file=+0($filename):ustring
./ftracetest: 22: echo: echo: I/O error
+ [ 1 -eq 1 ]
+ echo p:kgroup/kevent vfs_open file=+0($arg2)
./ftracetest: 25: echo: echo: I/O error

Please find attachment for the complete test output.

[Utkarsh Gupta (utkarsh)]

Ubuntu 22.10 (Kinetic Kudu) has reached end of life, so this bug will not be fixed for that specific release.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 2026592

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Brian Murray (brian-murray)]

Ubuntu 23.04 (Lunar Lobster) has reached end of life, so this bug will not be fixed for that specific release.