On 30/08/2018 - 16:33:48, Marc-André Lureau wrote:
> Remove -sandbox option if the host is not capable of TSYNC, since the
> sandbox will fail at setup time otherwise. This will help libvirt, for
> ex, to figure out if -sandbox will work.
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  qemu-seccomp.c | 19 ++++++++++++++++++-
>  vl.c           |  4 ++--
>  2 files changed, 20 insertions(+), 3 deletions(-)
> 
> diff --git a/qemu-seccomp.c b/qemu-seccomp.c
> index 4729eb107f..1baa5c69ed 100644
> --- a/qemu-seccomp.c
> +++ b/qemu-seccomp.c
> @@ -282,7 +282,24 @@ static QemuOptsList qemu_sandbox_opts = {
>  
>  static void seccomp_register(void)
>  {
> -    qemu_add_opts(&qemu_sandbox_opts);
> +    bool add = false;
> +
> +    /* FIXME: use seccomp_api_get() >= 2 check when released */
> +
> +#if defined(SECCOMP_FILTER_FLAG_TSYNC)
> +    int check;
> +
> +    /* check host TSYNC capability, it returns errno == ENOSYS if unavailable */
> +    check = qemu_seccomp(SECCOMP_SET_MODE_FILTER,
> +                         SECCOMP_FILTER_FLAG_TSYNC, NULL);
> +    if (check < 0 && errno == EFAULT) {
> +        add = true;
> +    }
> +#endif
> +
> +    if (add) {
> +        qemu_add_opts(&qemu_sandbox_opts);
> +    }
>  }
>  opts_init(seccomp_register);
>  #endif
> diff --git a/vl.c b/vl.c
> index 408bff9c1e..70c2449b86 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -4007,8 +4007,8 @@ int main(int argc, char **argv, char **envp)
>      }
>  
>  #ifdef CONFIG_SECCOMP
> -    if (qemu_opts_foreach(qemu_find_opts("sandbox"),
> -                          parse_sandbox, NULL, NULL)) {
> +    olist = qemu_find_opts_err("sandbox", NULL);
> +    if (olist && qemu_opts_foreach(olist, parse_sandbox, NULL, NULL)) {
>          exit(1);
>      }
>  #endif
> -- 
> 2.19.0.rc0.48.gb9dfa238d5
> 
Acked-by: Eduardo Otubo <otubo@redhat.com>