Subject: Re: [PATCH] vhost: add vsock compat ioctl

From: "Michael S. Tsirkin" <[email-masked]>
Date: Wed, 14 Mar 2018 21:05:31 +0200

On Wed, Mar 14, 2018 at 10:26:05AM -0700, Sonny Rao wrote:
> This will allow usage of vsock from 32-bit binaries on a 64-bit
> kernel.
> 
> Signed-off-by: Sonny Rao <[email-masked]>

I think you need to convert the pointer argument though.
Something along the lines of:

#ifdef CONFIG_COMPAT
static long vhost_vsock_dev_compat_ioctl(struct file *f, unsigned int ioctl,
					 unsigned long arg)
{
        return vhost_vsock_dev_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
} 
#endif  

> ---
>  drivers/vhost/vsock.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
> index 0d14e2ff19f16..d0e65e92110e5 100644
> --- a/drivers/vhost/vsock.c
> +++ b/drivers/vhost/vsock.c
> @@ -705,6 +705,7 @@ static const struct file_operations vhost_vsock_fops = {
>  	.release        = vhost_vsock_dev_release,
>  	.llseek		= noop_llseek,
>  	.unlocked_ioctl = vhost_vsock_dev_ioctl,
> +	.compat_ioctl   = vhost_vsock_dev_ioctl,
>  };
>  
>  static struct miscdevice vhost_vsock_misc = {
> -- 
> 2.13.5