[PATCH v3 1/3] selftests: kselftest: avoid cd - in runner

[Lorenzo Stoakes (ARM)]

On Sat, Sep 26, 2026 at 10:08:17AM +0900, Hajime Tazaki wrote:
> The kselftest runner currently uses `cd -` to restore its working
> directory after running a test.
>
> This is not supported by the minimal BusyBox hush shell used by some
> NOMMU targets. Store the original directory explicitly and restore it
> with a quoted path instead.
>
> This also avoids printing the directory change performed by `cd -` and
> handles paths containing whitespace correctly.
>
> Cc: Shuah Khan <shuah at kernel.org>
> Cc: Kees Cook <kees at kernel.org>
> Cc: Andy Lutomirski <luto at amacapital.net>
> Cc: Will Drewry <wad at chromium.org>
> Cc: Mark Brown <broonie at kernel.org>
> Cc: Brendan Jackman <brendan.jackman at linux.dev>
> Cc: Hangbin Liu <liuhangbin at gmail.com>
> Cc: "Ricardo B. Marliere" <rbm at suse.com>
> Cc: linux-kselftest at vger.kernel.org
> Cc: linux-um at lists.infradead.org
> Cc: linux-mm at kvack.org
> Signed-off-by: Hajime Tazaki <thehajime at gmail.com>

Looks fine to me so:

Reviewed-by: Lorenzo Stoakes (ARM) <ljs at kernel.org>

> ---
>  tools/testing/selftests/kselftest/runner.sh | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/kselftest/runner.sh b/tools/testing/selftests/kselftest/runner.sh
> index 311811dc55a0..8fc1018d6fec 100644
> --- a/tools/testing/selftests/kselftest/runner.sh
> +++ b/tools/testing/selftests/kselftest/runner.sh
> @@ -130,6 +130,7 @@ run_one()
>  				return $KSFT_FAIL
>  			fi
>  		fi
> +		OLDDIR=$(pwd)
>  		cd `dirname $TEST` > /dev/null
>  		(((( tap_timeout "$cmd" 2>&1; echo $? >&3) |
>  			tap_prefix >&4) 3>&1) |
> @@ -147,7 +148,7 @@ run_one()
>  		*)
>  			ktap_test_fail "$TEST_HDR_MSG # exit=$rc";;
>  		esac
> -		cd - >/dev/null
> +		cd "$OLDDIR" >/dev/null
>  	fi
>
>  	return $rc
> --
> 2.43.0
>

--
Cheers, Lorenzo