[PATCH 0/1] arm64: Add stack unwinder unit tests

["Ivan T. Ivanov" <iivanov@suse.de>]

Hi,

Here is my initial arm64 unwinder test support. Code is based on s390
unwinder tests, while errors introduced are mine. I am hopping that it
will be useful for testing and validating upcoming arm64
arch_stack_walk_reliable() support.

This patch is was tested on top of latest Madhavan work [1].

As expected unwinding trough IRQ fails. Here is the output of current
statue of affair:

# modprobe test_unwind
[   14.905945]     # Subtest: test_unwind
[   14.905948]     1..1
[   14.905949]         # Subtest: test_unwind_flags
[   14.906243]         ok 1 - UWM_DEFAULT
[   14.906375]         ok 2 - UWM_REGS
[   14.906902]         ok 3 - UWM_CALLER
[   14.907010]         ok 4 - UWM_CALLER | UWM_REGS
[   14.907220]         ok 5 - UWM_THREAD
[   14.907445]         ok 6 - UWM_THREAD | UWM_CALLER
[   14.912600]     # test_unwind_flags:  test_unwind+0x70/0x280 [test_unwind]
[   14.912602]     # test_unwind_flags:  unwindme_func4+0x64/0x260 [test_unwind]
[   14.912604]     # test_unwind_flags:  unwindme_func3+0x58/0x80 [test_unwind]
[   14.912605]     # test_unwind_flags:  unwindme_func2+0x18/0x28 [test_unwind]
[   14.912606]     # test_unwind_flags:  unwindme_func1+0x18/0x28 [test_unwind]
[   14.912607]     # test_unwind_flags:  unwindme_timer_fn+0x38/0x54 [test_unwind]
[   14.912608]     # test_unwind_flags:  call_timer_fn+0x38/0x1e0
[   14.912609]     # test_unwind_flags:  run_timer_softirq+0x500/0x550
[   14.912610]     # test_unwind_flags:  __do_softirq+0x124/0x3bc
[   14.912611]     # test_unwind_flags:  irq_exit_rcu+0xf0/0x110
[   14.912611]     # test_unwind_flags:  el1_interrupt+0x3c/0x70
[   14.912612]     # test_unwind_flags:  el1h_64_irq_handler+0x18/0x28
[   14.912612]     # test_unwind_flags:  el1h_64_irq+0x64/0x68
[   14.912613]     # test_unwind_flags:  arch_cpu_idle+0x18/0x28
[   14.912614]     # test_unwind_flags:  default_idle_call+0x6c/0x1d0
[   14.912614]     # test_unwind_flags:  do_idle+0x1f0/0x290
[   14.912615]     # test_unwind_flags:  cpu_startup_entry+0x30/0x38
[   14.912615]     # test_unwind_flags:  kernel_init+0x0/0x140
[   14.912616]     # test_unwind_flags:  arch_post_acpi_subsys_init+0x0/0x28
[   14.912617]     # test_unwind_flags:  start_kernel+0x6dc/0x718
[   14.912618]     # test_unwind_flags:  __primary_switched+0xc0/0xc8
[   14.912618]     # test_unwind_flags:
[   14.912644]     # test_unwind_flags: EXPECTATION FAILED at arch/arm64/kernel/test_unwind.c:501
[   14.912644]     Expected 0 == test_unwind_irq(&u), but
[   14.912644]         test_unwind_irq(&u) == -22
[   14.912656]         not ok 7 - UWM_IRQ
[   14.924625]     # test_unwind_flags:  unwindme_func4+0xa0/0x260 [test_unwind]
[   14.924630]     # test_unwind_flags:  unwindme_func3+0x58/0x80 [test_unwind]
[   14.924632]     # test_unwind_flags:  unwindme_func2+0x18/0x28 [test_unwind]
[   14.924634]     # test_unwind_flags:  unwindme_func1+0x18/0x28 [test_unwind]
[   14.924636]     # test_unwind_flags:  unwindme_timer_fn+0x38/0x54 [test_unwind]
[   14.924638]     # test_unwind_flags:  call_timer_fn+0x38/0x1e0
[   14.924639]     # test_unwind_flags:  run_timer_softirq+0x500/0x550
[   14.924641]     # test_unwind_flags:  __do_softirq+0x124/0x3bc
[   14.924643]     # test_unwind_flags:  irq_exit_rcu+0xf0/0x110
[   14.924645]     # test_unwind_flags:  el1_interrupt+0x3c/0x70
[   14.924646]     # test_unwind_flags:  el1h_64_irq_handler+0x18/0x28
[   14.924647]     # test_unwind_flags:  el1h_64_irq+0x64/0x68
[   14.924648]     # test_unwind_flags:  arch_cpu_idle+0x18/0x28
[   14.924649]     # test_unwind_flags:  default_idle_call+0x6c/0x1d0
[   14.924650]     # test_unwind_flags:  do_idle+0x1f0/0x290
[   14.924651]     # test_unwind_flags:  cpu_startup_entry+0x30/0x38
[   14.924653]     # test_unwind_flags:  kernel_init+0x0/0x140
[   14.924654]     # test_unwind_flags:  arch_post_acpi_subsys_init+0x0/0x28
[   14.924655]     # test_unwind_flags:  start_kernel+0x6dc/0x718
[   14.924656]     # test_unwind_flags:  __primary_switched+0xc0/0xc8
[   14.924657]     # test_unwind_flags:
[   14.924677]     # test_unwind_flags: EXPECTATION FAILED at arch/arm64/kernel/test_unwind.c:501
[   14.924677]     Expected 0 == test_unwind_irq(&u), but
[   14.924677]         test_unwind_irq(&u) == -22
[   14.924724]         not ok 8 - UWM_IRQ | UWM_REGS
[   14.936710]     # test_unwind_flags:  test_unwind+0x70/0x280 [test_unwind]
[   14.936717]     # test_unwind_flags:  unwindme_func4+0x64/0x260 [test_unwind]
[   14.936720]     # test_unwind_flags:  unwindme_func3+0x58/0x80 [test_unwind]
[   14.936722]     # test_unwind_flags:  unwindme_func2+0x18/0x28 [test_unwind]
[   14.936725]     # test_unwind_flags:  unwindme_func1+0x18/0x28 [test_unwind]
[   14.936727]     # test_unwind_flags:  unwindme_timer_fn+0x38/0x54 [test_unwind]
[   14.936729]     # test_unwind_flags:  call_timer_fn+0x38/0x1e0
[   14.936732]     # test_unwind_flags:  run_timer_softirq+0x500/0x550
[   14.936734]     # test_unwind_flags:  __do_softirq+0x124/0x3bc
[   14.936736]     # test_unwind_flags:  irq_exit_rcu+0xf0/0x110
[   14.936738]     # test_unwind_flags:  el1_interrupt+0x3c/0x70
[   14.936739]     # test_unwind_flags:  el1h_64_irq_handler+0x18/0x28
[   14.936741]     # test_unwind_flags:  el1h_64_irq+0x64/0x68
[   14.936743]     # test_unwind_flags:  arch_cpu_idle+0x18/0x28
[   14.936744]     # test_unwind_flags:  default_idle_call+0x6c/0x1d0
[   14.936746]     # test_unwind_flags:  do_idle+0x1f0/0x290
[   14.936748]     # test_unwind_flags:  cpu_startup_entry+0x30/0x38
[   14.936749]     # test_unwind_flags:  secondary_start_kernel+0x198/0x1c8
[   14.936751]     # test_unwind_flags:  __secondary_switched+0xa0/0xa4
[   14.936753]     # test_unwind_flags:
[   14.936839]     # test_unwind_flags: EXPECTATION FAILED at arch/arm64/kernel/test_unwind.c:501
[   14.936839]     Expected 0 == test_unwind_irq(&u), but
[   14.936839]         test_unwind_irq(&u) == -22
[   14.936874]         not ok 9 - UWM_IRQ | UWM_CALLER
[   14.944623]     # test_unwind_flags:  unwindme_func3+0x3c/0x80 [test_unwind]
[   14.944628]     # test_unwind_flags:  unwindme_func2+0x18/0x28 [test_unwind]
[   14.944631]     # test_unwind_flags:  unwindme_func1+0x18/0x28 [test_unwind]
[   14.944633]     # test_unwind_flags:  unwindme_timer_fn+0x38/0x54 [test_unwind]
[   14.944636]     # test_unwind_flags:  call_timer_fn+0x38/0x1e0
[   14.944638]     # test_unwind_flags:  run_timer_softirq+0x500/0x550
[   14.944641]     # test_unwind_flags:  __do_softirq+0x124/0x3bc
[   14.944643]     # test_unwind_flags:  irq_exit_rcu+0xf0/0x110
[   14.944646]     # test_unwind_flags:  el1_interrupt+0x3c/0x70
[   14.944649]     # test_unwind_flags:  el1h_64_irq_handler+0x18/0x28
[   14.944650]     # test_unwind_flags:  el1h_64_irq+0x64/0x68
[   14.944652]     # test_unwind_flags:  arch_cpu_idle+0x18/0x28
[   14.944654]     # test_unwind_flags:  default_idle_call+0x6c/0x1d0
[   14.944656]     # test_unwind_flags:  do_idle+0x1f0/0x290
[   14.944657]     # test_unwind_flags:  cpu_startup_entry+0x2c/0x38
[   14.944659]     # test_unwind_flags:  secondary_start_kernel+0x198/0x1c8
[   14.944661]     # test_unwind_flags:  __secondary_switched+0xa0/0xa4
[   14.944662]     # test_unwind_flags:
[   14.944687]     # test_unwind_flags: EXPECTATION FAILED at arch/arm64/kernel/test_unwind.c:501
[   14.944687]     Expected 0 == test_unwind_irq(&u), but
[   14.944687]         test_unwind_irq(&u) == -22
[   14.944737]         not ok 10 - UWM_IRQ | UWM_CALLER | UWM_REGS
[   14.945009]         ok 11 - UWM_REGS
[   14.945174]         ok 12 - UWM_KPROBE_ON_FTRACE
[   14.945299]         ok 13 - UWM_KPROBE_ON_FTRACE | UWM_REGS
[   14.946894]     # test_unwind_flags:  test_unwind+0x70/0x280 [test_unwind]
[   14.946902]     # test_unwind_flags:  test_unwind_ftrace_handler+0x28/0x40 [test_unwind]
[   14.946904]     # test_unwind_flags:  arch_ftrace_ops_list_func+0xd8/0x1b0
[   14.946906]     # test_unwind_flags:  ftrace_call+0x4/0x2c
[   14.946908]     # test_unwind_flags:  test_unwind_ftraced_func+0x8/0x28 [test_unwind]
[   14.946910]     # test_unwind_flags:  unwindme_func4+0x1b4/0x260 [test_unwind]
[   14.946912]     # test_unwind_flags:  unwindme_func3+0x58/0x80 [test_unwind]
[   14.946915]     # test_unwind_flags:  unwindme_func2+0x18/0x28 [test_unwind]
[   14.946917]     # test_unwind_flags:  unwindme_func1+0x18/0x28 [test_unwind]
[   14.946918]     # test_unwind_flags:  test_unwind_flags+0x5c/0x288 [test_unwind]
[   14.946920]     # test_unwind_flags:  kunit_try_run_case+0x58/0xc0 [kunit]
[   14.946921]     # test_unwind_flags:  kunit_generic_run_threadfn_adapter+0x28/0x38 [kunit]
[   14.946923]     # test_unwind_flags:  kthread+0x118/0x128
[   14.946924]     # test_unwind_flags:  ret_from_fork+0x10/0x20
[   14.946925]     # test_unwind_flags:
[   15.104639]     # test_unwind_flags: EXPECTATION FAILED at arch/arm64/kernel/test_unwind.c:503
[   15.104639]     Expected 0 == unwindme_func1(&u), but
[   15.104639]         unwindme_func1(&u) == -22
[   15.104691]         not ok 14 - UWM_FTRACE
[   15.240652]         ok 15 - UWM_FTRACE | UWM_REGS
[   15.264620]         ok 16 - UWM_KRETPROBE
[   15.292603]         ok 17 - UWM_KRETPROBE | UWM_REGS
[   15.293173]     # test_unwind_flags:  test_unwind+0x70/0x280 [test_unwind]
[   15.293175]     # test_unwind_flags:  kretprobe_ret_handler+0x38/0x50 [test_unwind]
[   15.293177]     # test_unwind_flags:  __kretprobe_trampoline_handler+0xec/0x188
[   15.293178]     # test_unwind_flags:  trampoline_probe_handler+0x30/0x50
[   15.293180]     # test_unwind_flags:  __kretprobe_trampoline+0x74/0xc8
[   15.293181]     # test_unwind_flags:  test_unwind_kretprobed_func_caller+0x18/0x28 [test_unwind]
[   15.293183]     # test_unwind_flags:  test_unwind_kretprobe+0xac/0x148 [test_unwind]
[   15.293185]     # test_unwind_flags:  unwindme_func4+0xf0/0x260 [test_unwind]
[   15.293186]     # test_unwind_flags:  unwindme_func3+0x58/0x80 [test_unwind]
[   15.293187]     # test_unwind_flags:  unwindme_func2+0x18/0x28 [test_unwind]
[   15.293188]     # test_unwind_flags:  unwindme_func1+0x18/0x28 [test_unwind]
[   15.293189]     # test_unwind_flags:  test_unwind_flags+0x5c/0x288 [test_unwind]
[   15.293190]     # test_unwind_flags:  kunit_try_run_case+0x58/0xc0 [kunit]
[   15.293191]     # test_unwind_flags:  kunit_generic_run_threadfn_adapter+0x28/0x38 [kunit]
[   15.293192]     # test_unwind_flags:  kthread+0x118/0x128
[   15.293192]     # test_unwind_flags:  ret_from_fork+0x10/0x20
[   15.293193]     # test_unwind_flags:
[   15.308570]     # test_unwind_flags: EXPECTATION FAILED at arch/arm64/kernel/test_unwind.c:503
[   15.308570]     Expected 0 == unwindme_func1(&u), but
[   15.308570]         unwindme_func1(&u) == -22
[   15.308611]         not ok 18 - UWM_KRETPROBE_HANDLER
[   15.324616]         ok 19 - UWM_KRETPROBE_HANDLER | UWM_REGS
[   15.324620]     # test_unwind_flags: pass:11 fail:6 skip:2 total:19
[   15.324623]     not ok 1 - test_unwind_flags
[   15.324626] # Totals: pass:11 fail:6 skip:2 total:19
[   15.324628] not ok 1 - test_unwind

Regards,
Ivan

[1] 20220617210717.27126-1-madvenka@linux.microsoft.com

Ivan T. Ivanov (1):
  arm64: Add initial set of stack unwinder self tests

 arch/arm64/Kconfig.debug        |  12 +
 arch/arm64/kernel/Makefile      |   1 +
 arch/arm64/kernel/stacktrace.c  |  23 ++
 arch/arm64/kernel/test_unwind.c | 518 ++++++++++++++++++++++++++++++++
 include/linux/stacktrace.h      |   1 +
 5 files changed, 555 insertions(+)
 create mode 100644 arch/arm64/kernel/test_unwind.c

-- 
2.35.3