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Wed, 9 Sep 2026 07:54:19 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Tianyi Chen In-Reply-To: References: Date: Wed, 9 Sep 2026 07:54:19 -0700 X-Gm-Features: AcwNN1UNxzL5WjMgcuf3-e2gvm86CJeujKJF0gUL8RZhHjcliTNAwngLs5rsPew Message-ID: Subject: [PATCH v3 RESEND 1/2] selftests/mm: Reject invalid test selections before running tests To: Andrew Morton , David Hildenbrand Cc: Shuah Khan , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Joel Savitz , Tianyi Chen Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Tianyi Chen Date: Tue, 08 Sep 2026 11:21:21 +0800 getopts reports unknown options and missing arguments, but run_vmtests.sh ignores its error result and continues with test setup. An empty -t argument also falls back to the default selection, while unknown category names can silently select no tests and still reach setup code. Exit on getopts errors and validate category names against the existing list in usage() before any test setup. Reject empty and whitespace-only selections, and normalize category separators so validation and execution agree. Initialize the default selection before parsing options so only -t changes the selection. Fixes: 85463321e726 ("selftests/vm: enable running select groups of tests") Assisted-by: LLM Signed-off-by: Tianyi Chen --- tools/testing/selftests/mm/run_vmtests.sh | 26 +++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/mm/run_vmtests.sh b/tools/testing/selftests/mm/run_vmtests.sh index d09f9f6a384e..9e62ab4c6775 100755 --- a/tools/testing/selftests/mm/run_vmtests.sh +++ b/tools/testing/selftests/mm/run_vmtests.sh @@ -96,26 +96,44 @@ separated by spaces: example: ./run_vmtests.sh -t "hmm mmap ksm" EOF - exit 0 } RUN_ALL=3Dfalse RUN_DESTRUCTIVE=3Dfalse TAP_PREFIX=3D"# " +VM_SELFTEST_ITEMS=3D"default" + while getopts "aht:nd" OPT; do case ${OPT} in "a") RUN_ALL=3Dtrue ;; - "h") usage ;; + "h") usage; exit 0 ;; "t") VM_SELFTEST_ITEMS=3D${OPTARG} ;; "n") TAP_PREFIX=3D ;; "d") RUN_DESTRUCTIVE=3Dtrue ;; + "?") exit 1 ;; esac done shift $((OPTIND -1)) -# default behavior: run all tests -VM_SELFTEST_ITEMS=3D${VM_SELFTEST_ITEMS:-default} +# Normalize whitespace so validation and test_selected() use the same name= s. +read -r -a selected_categories <<< "${VM_SELFTEST_ITEMS//$'\n'/ }" +VM_SELFTEST_ITEMS=3D"${selected_categories[*]}" +if [ -z "$VM_SELFTEST_ITEMS" ]; 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Wed, 09 Sep 2026 07:54:23 -0700 (PDT) Received: from 77377267392 named unknown by gmailapi.google.com with HTTPREST; Wed, 9 Sep 2026 10:54:23 -0400 Received: from 77377267392 named unknown by gmailapi.google.com with HTTPREST; Wed, 9 Sep 2026 10:54:23 -0400 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Tianyi Chen In-Reply-To: References: Date: Wed, 9 Sep 2026 10:54:23 -0400 X-Gm-Features: AcwNN1WLFkJxZiXjMeZLR_cyAMBfiX7lh_2ngWCAdTCfWBnsc8DM_11bZhuFLIg Message-ID: Subject: [PATCH v3 RESEND 2/2] selftests/mm: Only prepare ptrace_scope when memfd_secret is selected To: Andrew Morton , David Hildenbrand Cc: Shuah Khan , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Joel Savitz , Tianyi Chen Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Tianyi Chen Date: Tue, 08 Sep 2026 11:21:50 +0800 The memfd_secret setup clears ptrace_scope whenever its test binary is executable, even when a different category was selected. run_test() filters the test invocation, but it does not protect the preceding setup. Check the category selection before entering the memfd_secret block so running unrelated categories does not change ptrace_scope. Keep the existing executable check and the behavior when memfd_secret is selected. Acked-by: David Hildenbrand (Arm) Assisted-by: LLM Signed-off-by: Tianyi Chen --- tools/testing/selftests/mm/run_vmtests.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/run_vmtests.sh b/tools/testing/selftests/mm/run_vmtests.sh index 9e62ab4c6775..9bbef9410ccc 100755 --- a/tools/testing/selftests/mm/run_vmtests.sh +++ b/tools/testing/selftests/mm/run_vmtests.sh @@ -370,7 +370,7 @@ CATEGORY=3D"process_madv" run_test ./process_madv CATEGORY=3D"vma_merge" run_test ./merge -if [ -x ./memfd_secret ] +if test_selected "memfd_secret" && [ -x ./memfd_secret ] then if [ -f /proc/sys/kernel/yama/ptrace_scope ]; then (echo 0 > /proc/sys/kernel/yama/ptrace_scope 2>&1) | tap_prefix