[LTP] [PATCH v2] statmount09.c: Enable mnt_ns_id for STATMOUNT_MNT_NS_ID

[Andrea Cervesato]

Hi Cyril

On 9/26/25 9:32 AM, Andrea Cervesato wrote:
> Hi!
>
> On 9/26/25 6:07 AM, Jack Morgan wrote:
>> +#ifdef LTP_HAVE_STRUCT_STATMOUNT_MNT_NS_ID
>>       TST_EXP_EQ_LI(st_mount->mnt_ns_id, mnt_ns_id);
>> +#else
>> +    tst_res(TCONF, "statmount.mnt_ns_id not available in current 
>> headers, skipping check");
>> +#endif
>
> The statmount09 is testing STATMOUNT_MNT_NS_ID feature, which is 
> carrying the mnt_ns_id as well, so we don't need to run this test if 
> HAVE_STRUCT_STATMOUNT_MNT_NS_ID is not defined.
> We can do something like:
>
> diff --git a/configure.ac b/configure.ac
> index d4dd13033..189d8771e 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -264,6 +264,7 @@ AC_CHECK_TYPES([struct cachestat],,,[#include 
> <sys/mman.h>])
>  # Defined in <linux/mount.h>, but include/lapi/mount.h includes 
> <sys/mount.h> */
>  AC_CHECK_TYPES([struct mnt_id_req],,,[#include <sys/mount.h>])
>  AC_CHECK_TYPES([struct statmount],,,[#include <sys/mount.h>])
> +AC_CHECK_MEMBERS([struct statmount.mnt_ns_id],,,[#include 
> <linux/mount.h>])
>
>  AC_CHECK_TYPES([struct pidfd_info],,,[#include <sys/pidfd.h>])
>  AC_CHECK_TYPES([struct file_attr],,,[#include <linux/fs.h>])
> diff --git a/testcases/kernel/syscalls/statmount/statmount09.c 
> b/testcases/kernel/syscalls/statmount/statmount09.c
> index 20c76ba24..b78cec6b4 100644
> --- a/testcases/kernel/syscalls/statmount/statmount09.c
> +++ b/testcases/kernel/syscalls/statmount/statmount09.c
> @@ -15,6 +15,11 @@
>   *   namespace
>   */
>
> +#include "config.h"
> +#include "tst_test.h"
> +
> +#ifdef HAVE_STRUCT_STATMOUNT_MNT_NS_ID
> +
>  #define _GNU_SOURCE
>
>  #include "statmount.h"
> @@ -72,3 +77,8 @@ static struct tst_test test = {
>         }
>  };
>
> +#else
> +
> +TST_TEST_TCONF("STATMOUNT_MNT_NS_ID support is required");
> +
> +#endif
>
> This could be done by checking if STATMOUNT_MNT_NS_ID exists, but 
> since mnt_ns_id attribute and STATMOUNT_MNT_NS_ID are defined in the 
> same commit (09b31295f833031c88419550172703d45c5401e3 - fs: export the 
> mount ns id via statmount), we can safely use configure.ac.
>
> - Andrea
>
FYI this patch might be needed for the release, since it's breaking the 
build on old kernels before 09b31295f833031c88419550172703d45c5401e3 
commit. What do you think?

---
Andrea Cervesato

andrea.cervesato@suse.com