Re: [PATCH v2] selftests/lkdtm: Use "comm" instead of "diff" for dmesg

[Shuah Khan]

On 9/9/20 3:17 PM, Kees Cook wrote:
> Instead of full GNU diff (which smaller boot environments may not have),
> use "comm" which is more available.
>
> Reported-by: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx>
> Cc: Shuah Khan <shuah@xxxxxxxxxx>
> Cc: linux-kselftest@xxxxxxxxxxxxxxx
> Fixes: f131d9edc29d ("selftests/lkdtm: Don't clear dmesg when running tests")
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> ---
> v2: add --nocheck-order, thanks to Joe Lawrence
> v1: https://lore.kernel.org/lkml/202006261358.3E8AA623A9@keescook/
> ---
>   tools/testing/selftests/lkdtm/run.sh | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/lkdtm/run.sh b/tools/testing/selftests/lkdtm/run.sh
> index 8383eb89d88a..bb7a1775307b 100755
> --- a/tools/testing/selftests/lkdtm/run.sh
> +++ b/tools/testing/selftests/lkdtm/run.sh
> @@ -82,7 +82,7 @@ dmesg > "$DMESG"
>   ($SHELL -c 'cat <(echo '"$test"') >'"$TRIGGER" 2>/dev/null) || true
>   
>   # Record and dump the results
> -dmesg | diff --changed-group-format='%>' --unchanged-group-format='' "$DMESG" - > "$LOG" || true
> +dmesg | comm --nocheck-order -13 "$DMESG" - > "$LOG" || true
>   
>   cat "$LOG"
>   # Check for expected output

Greg,

Would you like me to take this through kselftest tree?

If you want to take it through lkdtm tree, here is my Ack:

Acked-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>

thanks,
-- Shuah