Re: [PATCH] selftests: pidfd: Fix compiling errors and warning

[Peter Seiderer <ps.report@gmx.net>]

Hello *,

On Wed,  5 Feb 2025 13:39:26 +0800, I Hsin Cheng <richard120310@gmail.com> wrote:

> When compiling selftests files under tools/testing/selftests/pidfd/ ,
> some compiling errors and warnings will pop out as the following.
> 
>   CC       pidfd_fdinfo_test
> pidfd_fdinfo_test.c: In function ‘child_fdinfo_nspid_test’:
> pidfd_fdinfo_test.c:231:13: warning: implicit declaration of function \
> ‘mount’ [-Wimplicit-function-declaration]
>   231 |         r = mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0);
>       |             ^~~~~
> pidfd_fdinfo_test.c:231:36: error: ‘MS_REC’ undeclared \
> (first use in this function)
>   231 |         r = mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0);
>       |                                    ^~~~~~
> pidfd_fdinfo_test.c:231:36: note: each undeclared identifier is \
> reported only once for each function it appears in
> pidfd_fdinfo_test.c:231:45: error: ‘MS_PRIVATE’ undeclared \
> (first use in this function); did you mean ‘MAP_PRIVATE’?
>   231 |         r = mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0);
>       |                                             ^~~~~~~~~~
>       |                                             MAP_PRIVATE
> pidfd_fdinfo_test.c:237:15: warning: implicit declaration of function \
> ‘umount2’; did you mean ‘SYS_umount2’? \
> [-Wimplicit-function-declaration]
>   237 |         (void)umount2("/proc", MNT_DETACH);
>       |               ^~~~~~~
>       |               SYS_umount2
> pidfd_fdinfo_test.c:237:32: error: ‘MNT_DETACH’ undeclared \
> (first use in this function)
>   237 |         (void)umount2("/proc", MNT_DETACH);
>       |                                ^~~~~~~~~~
> make: *** [../lib.mk:222: \
> ~/linux/tools/testing/selftests/pidfd/pidfd_fdinfo_test] Error 1
> 
> Solve these errors and warnings by including header file <sys/mount.h>.
> 
> Signed-off-by: I Hsin Cheng <richard120310@gmail.com>
> ---
>  tools/testing/selftests/pidfd/pidfd_fdinfo_test.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c b/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c
> index f062a986e..f718aac75 100644
> --- a/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c
> +++ b/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c
> @@ -13,6 +13,7 @@
>  #include <syscall.h>
>  #include <sys/wait.h>
>  #include <sys/mman.h>
> +#include <sys/mount.h>
>  
>  #include "pidfd.h"
>  #include "../kselftest.h"

Predated patch already available, see

	https://lore.kernel.org/linux-kselftest/20250115105211.390370-1-ps.report@gmx.net/

Regards,
Peter