Re: [PATCH 09/10] selftests/damon/sysfs_memcg_path_leak: fail only for real DAMON leak

[SJ Park <sj@kernel.org>]

On Thu, 17 Sep 2026 14:31:54 +0000 sashiko-bot@kernel.org wrote:

> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> - [Medium] selftests/damon: test falsely passes on minimal grep due to --quiet flag
> --
> 
> commit 3a025795f6efb7b8edc7858f005049159a83efbe
> Author: SJ Park <sj@kernel.org>
> 
> selftests/damon/sysfs_memcg_path_leak: fail only for real DAMON leak
> 
> This commit updates the DAMON sysfs_memcg_path_leak selftest to explicitly
> check the kmemleak report for "memcg_path_store". It exits with success if the
> leak doesn't appear to be related to DAMON, reducing false positive failures.
> 
> > diff --git a/tools/testing/selftests/damon/sysfs_memcg_path_leak.sh b/tools/testing/selftests/damon/sysfs_memcg_path_leak.sh
> > --- a/tools/testing/selftests/damon/sysfs_memcg_path_leak.sh
> > +++ b/tools/testing/selftests/damon/sysfs_memcg_path_leak.sh
> > @@ -41,5 +41,12 @@ if [ "$kmemleak_report" = "" ]
> >  then
> >  	exit 0
> >  fi
> > +if ! echo "$kmemleak_report" | grep "memcg_path_store" --quiet
> 
> [Severity: Medium]
> Will this script falsely pass in environments with a minimal grep
> implementation?
> 
> If this selftest is executed in an environment (like some BusyBox builds or
> Alpine Linux) where grep does not support the GNU --quiet extension, grep
> will exit with an error code. 
> 
> The ! operator will negate this non-zero exit code, causing the condition
> to evaluate to true. The script will then enter the then block and exit
> successfully (exit 0), potentially masking real kernel memory leaks.
> 
> Could this use -q instead of --quiet to be more portable?

I believe modern test infrastructures support --quiet.  So no blocker.  We can
revisit this if there is any report.

> 
> > +then
> > +	echo "[WARN] memleak found; apparently not from DAMON, though"
> > +	echo "$kmemleak_report"
> > +	exit 0
> > +fi
> > +
> >  echo "$kmemleak_report"
> >  exit 1
> 
> -- 
> Sashiko AI review · https://sashiko.dev/#/patchset/20260917142210.90829-1-sj@kernel.org?part=9


Thanks,
SJ