Re: [PATCH] fix dma-buf/udmabuf selftest

[Geert Uytterhoeven]

Hi Tom,

On Tue, Nov 27, 2018 at 7:53 PM Tom Murphy <murphyt7@xxxxxx> wrote:
> This patch fixes the udmabuf selftest. Currently the selftest is broken.
> I fixed the selftest by setting the F_SEAL_SHRINK seal on the memfd
> file descriptor which is required by udmabuf and added the test to
> the selftest Makefile.
>
> Signed-off-by: Tom Murphy <murphyt7@xxxxxx>

This is now commit 6edf2e3710f4ef25 ("fix dma-buf/udmabuf selftest").

> --- a/tools/testing/selftests/drivers/dma-buf/udmabuf.c
> +++ b/tools/testing/selftests/drivers/dma-buf/udmabuf.c
> @@ -4,7 +4,7 @@
>  #include <unistd.h>
>  #include <string.h>
>  #include <errno.h>
> -#include <fcntl.h>
> +#include <linux/fcntl.h>

Not including <fcntl.h> means we get

udmabuf.c:30:10: warning: implicit declaration of function âopenâ; did
you mean âpopenâ? [-Wimplicit-function-declaration]
  devfd = open("/dev/udmabuf", O_RDWR);
udmabuf.c:42:8: warning: implicit declaration of function âfcntlâ; did
you mean âfcvtâ? [-Wimplicit-function-declaration]
   ret = fcntl(memfd, F_ADD_SEALS, F_SEAL_SHRINK);

However, we need <linux/fcntl.h> for F_ADD_SEALS, F_SEAL_SHRINK.

Including both leads to lots of redefinition warnings.

Can we fix that?

>  #include <malloc.h>
>
>  #include <sys/ioctl.h>
> @@ -33,12 +33,19 @@ int main(int argc, char *argv[])
>                 exit(77);
>         }
>
> -       memfd = memfd_create("udmabuf-test", MFD_CLOEXEC);
> +       memfd = memfd_create("udmabuf-test", MFD_ALLOW_SEALING);
>         if (memfd < 0) {
>                 printf("%s: [skip,no-memfd]\n", TEST_PREFIX);
>                 exit(77);
>         }
>
> +       ret = fcntl(memfd, F_ADD_SEALS, F_SEAL_SHRINK);
> +       if (ret < 0) {
> +               printf("%s: [skip,fcntl-add-seals]\n", TEST_PREFIX);
> +               exit(77);
> +       }
> +
> +
>         size = getpagesize() * NUM_PAGES;
>         ret = ftruncate(memfd, size);
>         if (ret == -1) {

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds