Re: [PATCH v2 1/2] selftests: mm: ksm: Fix incorrect evaluation of parameter

From: Stefan Roesch
Date: Tue Aug 08 2023 - 17:53:20 EST



Ayush Jain <ayush.jain3@xxxxxxx> writes:

> A missing break in kms_tests leads to kselftest hang when the
> parameter -s is used.
> In current code flow because of missing break in -s, -t parses
> args spilled from -s and as -t accepts only valid values as 0,1
> so any arg in -s >1 or <0, gets in ksm_test failure
>
> This went undetected since, before the addition of option -t,
> the next case -M would immediately break out of the switch
> statement but that is no longer the case
>
> Add the missing break statement.
>
> ----Before----
> ./ksm_tests -H -s 100
> Invalid merge type
>
> ----After----
> ./ksm_tests -H -s 100
> Number of normal pages: 0
> Number of huge pages: 50
> Total size: 100 MiB
> Total time: 0.401732682 s
> Average speed: 248.922 MiB/s
>
> Fixes: 07115fcc15b4 ("selftests/mm: add new selftests for KSM")
>
> Signed-off-by: Ayush Jain <ayush.jain3@xxxxxxx>
> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
> ---
> v1 -> v2
> collect Reviewed-by from David
> Updated Fixes tag from commit 9e7cb94ca218 to 07115fcc15b4
>
> tools/testing/selftests/mm/ksm_tests.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/tools/testing/selftests/mm/ksm_tests.c b/tools/testing/selftests/mm/ksm_tests.c
> index 435acebdc325..380b691d3eb9 100644
> --- a/tools/testing/selftests/mm/ksm_tests.c
> +++ b/tools/testing/selftests/mm/ksm_tests.c
> @@ -831,6 +831,7 @@ int main(int argc, char *argv[])
> printf("Size must be greater than 0\n");
> return KSFT_FAIL;
> }
> + break;
> case 't':
> {
> int tmp = atoi(optarg);

Acked-by: Stefan Roesch <shr@xxxxxxxxxxxx>