tests/kern/t31 fstest fails on newer kernels (6.6.45 OK, 6.9.3 FAIL)

[garlick]

Problem: tests/kern/t31 fails on kernel 6.9.3 (ubuntu 22.04)

Test Summary Report
-------------------
tests/chown/00.t   (Wstat: 0 Tests: 171 Failed: 19)
  Failed tests:  34-37, 68-69, 83-84, 116-118, 122-124, 129-130
                135-137
tests/chown/05.t   (Wstat: 0 Tests: 15 Failed: 3)
  Failed tests:  5-6, 10
tests/open/06.t    (Wstat: 0 Tests: 72 Failed: 3)
  Failed tests:  9-11
Result: FAIL

[garlick]

Noted in #108

I've run these tests on Yocto kernel 6.6.45, which may be why kern/t31 passes

[garlick]

Another data point: this test passes in ubuntu-22.04 CI with the following kernel

Linux fv-az570-511 6.5.0-1025-azure #26~22.04.1-Ubuntu SMP Thu Jul 11 22:33:04 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

[garlick]

Hmm, just noted this is passing now on my home system, still at kernel 6.9.3. I'm not sure what changed.

[snogge]

t31 passes for me on Yocto with kernel 6.12 and diod master dca6145. It may be problems with which kernel configs I had enabled for the kernel previously.

My current status is that

• t43 fails as expected
• t40 is skipped as scrub is not available in Yocto at the moment
• t32 has to be disabled because dbench does not seem to work in the default qemu setup

So this issue can be closed.

[garlick]

OK, thanks for the follow up. I did observe this failure on my home system too as noted above, but then it mysteriously starting working again. I'm OK with closing this for now. We can revisit if we are having more problems.

[garlick]

Oh, I think I have an explanation for this one. If configure doesn't find libcap then it silently disables "DAC bypass".

The failure can be reproduced by commenting out the setting of SRV_FLAGS_DAC_BYPASS in diod.c.

If we need it, libpcap should be a hard requirement. I'm not sure I completely understand why we need it - need to refresh my memory.