[linus:master] [selftests] 465b05bae5: kernel-selftests.landlock.audit_test.audit.tsync_override_log_subdomains_off.fail

[Thomas Weißschuh]

On Mon, May 18, 2026 at 11:30:42AM +0200, Mickaël Salaün wrote:
> On Mon, May 18, 2026 at 10:48:27AM +0200, Thomas Weißschuh wrote:
> > On Wed, May 13, 2026 at 12:52:35PM +0200, Mickaël Salaün wrote:
> > (...)
> > 
> > > > > config: x86_64-rhel-9.4-kselftests
> > > > > compiler: gcc-14
> > > > > test machine: 16 threads Intel(R) Core(TM) i7-13620H (Raptor Lake) with 32G memory
> > > > > 
> > > > > (please refer to attached dmesg/kmsg for entire log/backtrace)
> > > > > 
> > > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > > > > the same patch/commit), kindly add following tags
> > > > > | Reported-by: kernel test robot <oliver.sang at intel.com>
> > > > > | Closes: https://lore.kernel.org/oe-lkp/202605111649.a8b30a62-lkp@intel.com
> > > > 
> > > > I was unable to run the landlock selftests myself, on my machines they are
> > > > failing at runtime with all kinds of colorful errors. Are the requirements
> > > > explained somewhere?
> > > 
> > > I'm curious about the errors you get.  They are standard kselftests that
> > > should work following this workflow:
> > > 
> > >   make TARGETS=landlock O=build kselftest-gen_tar
> > > 
> > > and then running ./build/kselftests/kselftest_install/run_kselftest.sh
> > > as root in a VM.  The required kernel configuration is listed in
> > > tools/testing/selftests/landlock/config
> > 
> > So there are two root issues I ran into:
> > 
> > 1) The tests can not be executed from virtiofs (as set up by virtme-ng):
> 
> Most filesystem tests initially set up tmpfs and then use it.
> 
> I'm using virtme-ng too, see the
> https://github.com/landlock-lsm/landlock-test-tools
> 
>  ARCH=x86_64 .../check-linux.sh build_light kselftest
> 
> > 
> >  #  RUN           audit.layers ...
> > # audit_test.c:52:layers:Expected 0 (0) <= self->audit_fd (-13)
> > # audit_test.c:61:layers:Failed to initialize audit: Permission denied
> > # layers: Test failed
> > #          FAIL  audit.layers
> > not ok 1 audit.layers
> > 
> > (The same for all other testcases)
> 
> It looks like the tests are not run with enough privileges.  Do you run
> them as root?  Does the kernel has the required config set?

Yes. The exact same setup works when executed from a tmpfs.

> > 2) $PWD needs to be the test binary directory for "./wait-pipe-sandbox" to work.
> 
> Yes.  run_kselftest.sh should handle that.

Fair enough. The selftests I used so far worked just fine when executed directly.
Maybe only I am using them this way. Some better diagnostics would have saved
me some time. Consider it a suggestion.

> > > To make it easier, we wrote a wrapper to test everything with UML:
> > > https://github.com/landlock-lsm/landlock-test-tools (see check-linux.sh)
> > > 
> > > > 
> > > > > # #  RUN           audit.tsync_override_log_subdomains_off ...
> > > > > # # audit_test.c:591:tsync_override_log_subdomains_off:Expected 0 (0) == matches_log_signal(_metadata, self->audit_fd, child_data.parent_pid, NULL) (-11)
> > > > 
> > > > This error number means "EAGAIN 11 Resource temporarily unavailable",
> > > > so it could be a temporary error.
> > > 
> > > Yes, the test is flaky under pressure.
> > > 
> > > > 
> > > > Can you reproduce this issue? Is it really dependent on my patch as
> > > > blamed above? If so, does the selftest rely on the previous, incorrect order?
> > > 
> > > I don't think it directly depends on your patch but it might be a side
> > > effect.  Anyway, I've been working on fixing this kind of issue and just
> > > sent a fix:
> > > https://lore.kernel.org/r/20260513105112.140137-2-mic@digikod.net
> > 
> > Thanks, unfortunately I can't validate that it will fix the issue at hand.
> 
> I pushed it to -next, we'll see but I'm pretty sure this is the issue.

Nice. I justed wanted to make clear that I won't be able to provide a Tested-by.


Thanks again,
Thomas