[LTP] [PATCH] userfaultfd05: allow TCONF when UFFD-WP is unsupported

[Petr Vorel]

Hi Li,

> On system without enable CONFIG_HAVE_ARCH_USERFAULTFD_WP kernel option,
> test will fail like below:

>   userfaultfd05.c:95: TBROK: ioctl(3,((((2U|1U) << (((0+8)+8)+14)) |
>     (((0xAA)) << (0+8)) | ((((0x3F))) << 0) |
>     ((((sizeof(struct uffdio_api)))) << ((0+8)+8)))),...)
>    	 failed: EINVAL (22)

> The original test uses SAFE_IOCTL macro, which prematurely triggers
> TBROK and prevents the test from verifying UFFD_FEATURE_PAGEFAULT_FLAG_WP.

Good catch. I don't have any kernel without UFFD_FEATURE_PAGEFAULT_FLAG_WP,
therefore I didn't notice.

Fixes: efd8e51008 ("userfaultfd: Add test using UFFDIO_WRITEPROTECT")

> Signed-off-by: Li Wang <liwang@redhat.com>
> Cc: Christian Amann <camann@suse.com>
> Cc: Ricardo Branco <rbranco@suse.com>
> ---
>  testcases/kernel/syscalls/userfaultfd/userfaultfd05.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)

> diff --git a/testcases/kernel/syscalls/userfaultfd/userfaultfd05.c b/testcases/kernel/syscalls/userfaultfd/userfaultfd05.c
> index c4edc2529..9cb0bb08f 100644
> --- a/testcases/kernel/syscalls/userfaultfd/userfaultfd05.c
> +++ b/testcases/kernel/syscalls/userfaultfd/userfaultfd05.c
> @@ -92,11 +92,11 @@ static void run(void)

>  	uffdio_api.api = UFFD_API;
>  	uffdio_api.features = UFFD_FEATURE_PAGEFAULT_FLAG_WP;
> -	SAFE_IOCTL(uffd, UFFDIO_API, &uffdio_api);
> +	if (ioctl(uffd, UFFDIO_API, &uffdio_api) < 0) {
> +		if (!(uffdio_api.features & UFFD_FEATURE_PAGEFAULT_FLAG_WP))
> +			tst_brk(TCONF, "UFFD write-protect unsupported");

> -	if (!(uffdio_api.features & UFFD_FEATURE_PAGEFAULT_FLAG_WP)) {
> -		tst_brk(TCONF, "UFFD write-protect unsupported");
> -		return;
> +		tst_brk(TBROK | TERRNO, "ioctl_userfaultfd failed");
very nit: I would write "ioctl() on userfaultfd failed"?  I was thinking what
ioctl_userfaultfd is, but ok, there is man ioctl_userfaultfd(2).

Kind regards,
Petr
>  	}

>  	uffdio_register.range.start = (unsigned long) page;