Re: [main-line][PowerPC]selftests/powerpc/signal: sigfuz fails

[Venkat Rao Bagalkote <venkat88@linux.ibm.com>]

Thanks Michael and Maddy for the feedback.

On 18/03/25 4:20 pm, Madhavan Srinivasan wrote:
> On 3/17/25 4:43 PM, Michael Ellerman wrote:
>> Venkat Rao Bagalkote<venkat88@linux.ibm.com> writes:
>>> Greetings!!
>>>
>>> I am observing selftests/powerpc/signal:sigfuz test fails on linux
>>> mainline repo on IBM Power10 systems.
>>>
>>> The test passes on the kernel with commit head:
>>> 619f0b6fad524f08d493a98d55bac9ab8895e3a6 and fails on the kernel with
>>> commit head: ce69b4019001407f9cd738dd2ba217b3a8ab831b on the main line.
>>>
>>>
>>> Repo:https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
>>>
>>> I tried to do git bisect and the bisect tool pointed first bad commit
>>> to: 16ebb6f5b6295c9688749862a39a4889c56227f8.
>>>
>>> But upon reverting the first bad commit issue is still seen. So please
>>> ignore, if the bisection dosent help.
>>>
>>>
>>> Error:
>>>
>>> # selftests: powerpc/signal: sigfuz
>>> # test: signal_fuzzer
>>> # tags: git_version:v6.14-rc7-1-g49c747976afa
>>> # !! killing signal_fuzzer
>>> # !! child died by signal 15
>>> # failure: signal_fuzzer
>>> not ok 3 selftests: powerpc/signal: sigfuz # exit=1
>> That error means the test is timing out and being killed by the test
>> harness.
>>
> I tired multiple times with the config shared by Venkat in my P10 LPAR
> and it always passes for me with default timeout as 0.
>
>
> ok 2 selftests: powerpc/signal: signal_tm
> # timeout set to 0
> # selftests: powerpc/signal: sigfuz
> # test: signal_fuzzer
> # tags: git_version:v6.14-rc2-61-g861efb8a48ee
> # success: signal_fuzzer
> ok 3 selftests: powerpc/signal: sigfuz
> # timeout set to 0
> # selftests: powerpc/signal: sigreturn_vdso
> # test: sigreturn_vdso
> # tags: git_version:v6.14-rc2-61-g861efb8a48ee
> # VDSO is at 0x7fff9aac0000-0x7fff9aacffff (65536 bytes)
> # Signal delivered OK with VDSO mapped
> # VDSO moved to 0x7fff9aa50000-0x7fff9aa5ffff (65536 bytes)
> # Signal delivered OK with VDSO moved
> # Unmapped VDSO
> # Remapped the stack executable
> # Signal delivered OK with VDSO unmapped
> # success: sigreturn_vdso
>
>
> Setup: P10 LPAR with 16CPUs, LPAR running only the selftest
> Kernel: powerpc/next (861efb8a48ee), config shared by venkat
>
> Maddy
>
>
> One key difference which I could figure out so far in the set up is, mine is Power10 system running on P11 FW.
>
> I quickly gave a try with P10 system with P10 FW, and issue is not seen.
>
> Logs from P10 system running on P10 FW:
>
> make -j 33 -C powerpc/signal/ run_tests make: Entering directory 
> '/root/venkat/linux/tools/testing/selftests/powerpc/signal' TAP 
> version 13 1..7 # timeout set to 0 # selftests: powerpc/signal: signal 
> # test: signal # tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # 
> success: signal ok 1 selftests: powerpc/signal: signal # timeout set 
> to 0 # selftests: powerpc/signal: signal_tm # test: signal_tm # tags: 
> git_version:v6.14-rc7-69-g81e4f8d68c66 # [SKIP] Test skipped on line 
> 58 # skip: signal_tm ok 2 selftests: powerpc/signal: signal_tm # 
> timeout set to 0 # selftests: powerpc/signal: sigfuz # test: 
> signal_fuzzer # tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # 
> success: signal_fuzzer ok 3 selftests: powerpc/signal: sigfuz # 
> timeout set to 0 # selftests: powerpc/signal: sigreturn_vdso # test: 
> sigreturn_vdso # tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # VDSO 
> is at 0x7fffae2e0000-0x7fffae2effff (65536 bytes) # Signal delivered 
> OK with VDSO mapped # VDSO moved to 0x7fffae270000-0x7fffae27ffff 
> (65536 bytes) # Signal delivered OK with VDSO moved # Unmapped VDSO # 
> Remapped the stack executable # Signal delivered OK with VDSO unmapped 
> # success: sigreturn_vdso ok 4 selftests: powerpc/signal: 
> sigreturn_vdso # timeout set to 0 # selftests: powerpc/signal: 
> sig_sc_double_restart # test: sig sys restart # tags: 
> git_version:v6.14-rc7-69-g81e4f8d68c66 # success: sig sys restart ok 5 
> selftests: powerpc/signal: sig_sc_double_restart # timeout set to 0 # 
> selftests: powerpc/signal: sigreturn_kernel # test: sigreturn_kernel # 
> tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # All children killed as 
> expected # success: sigreturn_kernel ok 6 selftests: powerpc/signal: 
> sigreturn_kernel # timeout set to 0 # selftests: powerpc/signal: 
> sigreturn_unaligned # test: sigreturn_unaligned # tags: 
> git_version:v6.14-rc7-69-g81e4f8d68c66 # success: sigreturn_unaligned 
> ok 7 selftests: powerpc/signal: sigreturn_unaligned make: Leaving 
> directory '/root/venkat/linux/tools/testing/selftests/powerpc/signal'
>> That could be due to a bug, but it could just be that your system is
>> overloaded or something. You can increase the timeout in the code by
>> adding a call to test_harness_timeout().
>>
>> The test also includes lots of randomisation, so if you actually need to
>> bisect it you'd want to change the code to use a consistent random seed
>> in the calls to srand().
>>
>> cheers
> I increased the timeout from 0 to 120, I still see the issue.
>
> Below are the logs with and with out time out.
>
> make -j 33 -C powerpc/signal/ run_tests all clean clean_mods_dir 
> emit_tests gen_mods_dir install run_tests [root@ltcden8-lp3 
> selftests]# make -j 33 -C powerpc/signal/ run_tests make: Entering 
> directory '/root/linux/tools/testing/selftests/powerpc/signal' CC 
> signal CC signal_tm CC sigfuz CC sigreturn_vdso CC 
> sig_sc_double_restart CC sigreturn_kernel CC sigreturn_unaligned TAP 
> version 13 1..7 # timeout set to 0 # selftests: powerpc/signal: signal 
> # test: signal # tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # 
> success: signal ok 1 selftests: powerpc/signal: signal # timeout set 
> to 0 # selftests: powerpc/signal: signal_tm # test: signal_tm # tags: 
> git_version:v6.14-rc7-69-g81e4f8d68c66 # [SKIP] Test skipped on line 
> 58 # skip: signal_tm ok 2 selftests: powerpc/signal: signal_tm # 
> timeout set to 0 # selftests: powerpc/signal: sigfuz # test: 
> signal_fuzzer # tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # !! 
> killing signal_fuzzer # !! child died by signal 15 # failure: 
> signal_fuzzer not ok 3 selftests: powerpc/signal: sigfuz # exit=1 # 
> timeout set to 0 # selftests: powerpc/signal: sigreturn_vdso # test: 
> sigreturn_vdso # tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # VDSO 
> is at 0x7fffb1860000-0x7fffb186ffff (65536 bytes) # Signal delivered 
> OK with VDSO mapped # VDSO moved to 0x7fffb17f0000-0x7fffb17fffff 
> (65536 bytes) # Signal delivered OK with VDSO moved # Unmapped VDSO # 
> Remapped the stack executable # Signal delivered OK with VDSO unmapped 
> # success: sigreturn_vdso ok 4 selftests: powerpc/signal: 
> sigreturn_vdso # timeout set to 0 # selftests: powerpc/signal: 
> sig_sc_double_restart # test: sig sys restart # tags: 
> git_version:v6.14-rc7-69-g81e4f8d68c66 # success: sig sys restart ok 5 
> selftests: powerpc/signal: sig_sc_double_restart # timeout set to 0 # 
> selftests: powerpc/signal: sigreturn_kernel # test: sigreturn_kernel # 
> tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # All children killed as 
> expected # success: sigreturn_kernel ok 6 selftests: powerpc/signal: 
> sigreturn_kernel # timeout set to 0 # selftests: powerpc/signal: 
> sigreturn_unaligned # test: sigreturn_unaligned # tags: 
> git_version:v6.14-rc7-69-g81e4f8d68c66 # success: sigreturn_unaligned 
> ok 7 selftests: powerpc/signal: sigreturn_unaligned make: Leaving 
> directory '/root/linux/tools/testing/selftests/powerpc/signal'
> # vi powerpc/signal/settings make -j 33 -C powerpc/signal/ run_tests 
> make: Entering directory 
> '/root/linux/tools/testing/selftests/powerpc/signal' TAP version 13 
> 1..7 # timeout set to 120 # selftests: powerpc/signal: signal # test: 
> signal # tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # success: 
> signal ok 1 selftests: powerpc/signal: signal # timeout set to 120 # 
> selftests: powerpc/signal: signal_tm # test: signal_tm # tags: 
> git_version:v6.14-rc7-69-g81e4f8d68c66 # [SKIP] Test skipped on line 
> 58 # skip: signal_tm ok 2 selftests: powerpc/signal: signal_tm # 
> timeout set to 120 # selftests: powerpc/signal: sigfuz # test: 
> signal_fuzzer # tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # not ok 
> 3 selftests: powerpc/signal: sigfuz # TIMEOUT 120 seconds # timeout 
> set to 120 # selftests: powerpc/signal: sigreturn_vdso # test: 
> sigreturn_vdso # tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # VDSO 
> is at 0x7fff8b170000-0x7fff8b17ffff (65536 bytes) # Signal delivered 
> OK with VDSO mapped # VDSO moved to 0x7fff8b100000-0x7fff8b10ffff 
> (65536 bytes) # Signal delivered OK with VDSO moved # Unmapped VDSO # 
> Remapped the stack executable # Signal delivered OK with VDSO unmapped 
> # success: sigreturn_vdso ok 4 selftests: powerpc/signal: 
> sigreturn_vdso # timeout set to 120 # selftests: powerpc/signal: 
> sig_sc_double_restart # test: sig sys restart # tags: 
> git_version:v6.14-rc7-69-g81e4f8d68c66 # success: sig sys restart ok 5 
> selftests: powerpc/signal: sig_sc_double_restart # timeout set to 120 
> # selftests: powerpc/signal: sigreturn_kernel # test: sigreturn_kernel 
> # tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # All children killed 
> as expected # success: sigreturn_kernel ok 6 selftests: 
> powerpc/signal: sigreturn_kernel # timeout set to 120 # selftests: 
> powerpc/signal: sigreturn_unaligned # test: sigreturn_unaligned # 
> tags: git_version:v6.14-rc7-69-g81e4f8d68c66 # success: 
> sigreturn_unaligned ok 7 selftests: powerpc/signal: 
> sigreturn_unaligned make: Leaving directory 
> '/root/linux/tools/testing/selftests/powerpc/signal' [root@ltcden8-lp3 
> selftests]# [root@ltcden8-lp3 selftests]# [root@ltcden8-lp3 
> selftests]# uname -r 6.14.0-rc7-00069-g81e4f8d68c66 [root@ltcden8-lp3 
> selftests]#


Regards,

Venkat.