Re: [PATCH net-next] vringh: fix copy direction of vringh_iov_push_kern()

[Michael S. Tsirkin]

On Thu, Oct 24, 2019 at 11:57:18AM +0800, Jason Wang wrote:
> We want to copy from iov to buf, so the direction was wrong.
> 
> Note: no real user for the helper, but it will be used by future
> features.
> 
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>

I'm still inclined to merge it now, incorrect code tends to
proliferate.

> ---
>  drivers/vhost/vringh.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c
> index 08ad0d1f0476..a0a2d74967ef 100644
> --- a/drivers/vhost/vringh.c
> +++ b/drivers/vhost/vringh.c
> @@ -852,6 +852,12 @@ static inline int xfer_kern(void *src, void *dst, size_t len)
>  	return 0;
>  }
>  
> +static inline int kern_xfer(void *dst, void *src, size_t len)
> +{
> +	memcpy(dst, src, len);
> +	return 0;
> +}
> +
>  /**
>   * vringh_init_kern - initialize a vringh for a kernelspace vring.
>   * @vrh: the vringh to initialize.
> @@ -958,7 +964,7 @@ EXPORT_SYMBOL(vringh_iov_pull_kern);
>  ssize_t vringh_iov_push_kern(struct vringh_kiov *wiov,
>  			     const void *src, size_t len)
>  {
> -	return vringh_iov_xfer(wiov, (void *)src, len, xfer_kern);
> +	return vringh_iov_xfer(wiov, (void *)src, len, kern_xfer);
>  }
>  EXPORT_SYMBOL(vringh_iov_push_kern);
>  
> -- 
> 2.19.1