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Message-ID: <0dbe701a-99c1-4606-915e-1f1c67802f64@linuxfoundation.org>
Date: Tue, 26 Mar 2024 13:28:41 -0600
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Subject: Re: [PATCH] selftests/harness: Prevent infinite loop due to Assert in
 FIXTURE_TEARDOWN
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To: Shengyu Li <shengyu.li.evgeny@gmail.com>, shuah@kernel.org
Cc: luto@amacapital.net, linux-kselftest@vger.kernel.org,
 linux-kernel@vger.kernel.org, wad@chromium.org,
 Shuah Khan <skhan@linuxfoundation.org>
References: <20240314224323.23201-1-shengyu.li.evgeny@gmail.com>
From: Shuah Khan <skhan@linuxfoundation.org>
In-Reply-To: <20240314224323.23201-1-shengyu.li.evgeny@gmail.com>
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On 3/14/24 16:43, Shengyu Li wrote:
> This patch addresses an issue in the selftests/harness where an assertion within FIXTURE_TEARDOWN could trigger an infinite loop. The problem arises because the teardown procedure is meant to execute once, but the presence of failing assertions (ASSERT_EQ(0, 1)) leads to repeated attempts to execute teardown due to the long jump mechanism used by the harness for handling assertions.
> 
> To resolve this, the patch ensures that the teardown process runs only once, regardless of assertion outcomes, preventing the infinite loop and allowing tests to fail.
> 

Please make sure change log is formatted with 70-75 character
long lines.

Please include information on how you found this problem.

Send v2 with that change.

> Signed-off-by: Shengyu Li <shengyu.li.evgeny@gmail.com>
> ---
>   tools/testing/selftests/kselftest_harness.h | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
> index 4fd735e48ee7..230d62884885 100644
> --- a/tools/testing/selftests/kselftest_harness.h
> +++ b/tools/testing/selftests/kselftest_harness.h
> @@ -383,6 +383,7 @@
>   		FIXTURE_DATA(fixture_name) self; \
>   		pid_t child = 1; \
>   		int status = 0; \
> +		bool jmp = false; \
>   		memset(&self, 0, sizeof(FIXTURE_DATA(fixture_name))); \
>   		if (setjmp(_metadata->env) == 0) { \
>   			/* Use the same _metadata. */ \
> @@ -399,8 +400,10 @@
>   				_metadata->exit_code = KSFT_FAIL; \
>   			} \
>   		} \
> +		else \
> +			jmp = true; \
>   		if (child == 0) { \
> -			if (_metadata->setup_completed && !_metadata->teardown_parent) \
> +			if (_metadata->setup_completed && !_metadata->teardown_parent && !jmp) \
>   				fixture_name##_teardown(_metadata, &self, variant->data); \
>   			_exit(0); \
>   		} \

thanks,
-- Shuah