Re: [PATCH] selftests/cgroup: Fix build on older distros

[Sachin Sant]

> On 04-Nov-2020, at 3:35 PM, Michael Ellerman <mpe@xxxxxxxxxxxxxx> wrote:
> 
> On older distros struct clone_args does not have a cgroup member,
> leading to build errors:
> 
>  cgroup_util.c: In function 'clone_into_cgroup':
>  cgroup_util.c:343:4: error: 'struct clone_args' has no member named 'cgroup'
> 
> But the selftests already have a locally defined version of the
> structure which is up to date, called __clone_args.
> 
> So use __clone_args which fixes the error.
> 

Argument passed to sys_clone3() will also require a similar change.

-	pid = sys_clone3(&args, sizeof(struct clone_args));
+	pid = sys_clone3(&args, sizeof(struct __clone_args));

Without this compilation still fails(at least for me) due to following error

cgroup_util.c: In function 'clone_into_cgroup':
cgroup_util.c:346:33: error: invalid application of 'sizeof' to incomplete type 'struct clone_args'
  pid = sys_clone3(&args, sizeof(struct clone_args));

> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> ---
> tools/testing/selftests/cgroup/cgroup_util.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/cgroup/cgroup_util.c b/tools/testing/selftests/cgroup/cgroup_util.c
> index 05853b0b8831..58e30f65df5e 100644
> --- a/tools/testing/selftests/cgroup/cgroup_util.c
> +++ b/tools/testing/selftests/cgroup/cgroup_util.c
> @@ -337,7 +337,7 @@ pid_t clone_into_cgroup(int cgroup_fd)
> #ifdef CLONE_ARGS_SIZE_VER2
> 	pid_t pid;
> 
> -	struct clone_args args = {
> +	struct __clone_args args = {
> 		.flags = CLONE_INTO_CGROUP,
> 		.exit_signal = SIGCHLD,
> 		.cgroup = cgroup_fd,
> 
> base-commit: cf7cd542d1b538f6e9e83490bc090dd773f4266d
> -- 
> 2.25.1
>