Re: [PATCH V2 08/14] Drivers: hv: balloon: Fix info request to show max page count

[Dan Carpenter <dan.carpenter@oracle.com>]

On Tue, Nov 01, 2016 at 01:07:28PM -0700, kys@exchange.microsoft.com wrote:
> From: Alex Ng <alexng@messages.microsoft.com>
> 
> Balloon driver was only printing the size of the info blob and not the
> actual content. This fixes it so that the info blob (max page count as
> configured in Hyper-V) is printed out.
> 
> Signed-off-by: Alex Ng <alexng@microsoft.com>
> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
> ---
>  drivers/hv/hv_balloon.c |    9 +++++++--
>  1 files changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
> index 8cac29a..14c3dc4 100644
> --- a/drivers/hv/hv_balloon.c
> +++ b/drivers/hv/hv_balloon.c
> @@ -1034,8 +1034,13 @@ static void process_info(struct hv_dynmem_device *dm, struct dm_info_msg *msg)
>  
>  	switch (info_hdr->type) {
>  	case INFO_TYPE_MAX_PAGE_CNT:
> -		pr_info("Received INFO_TYPE_MAX_PAGE_CNT\n");
> -		pr_info("Data Size is %d\n", info_hdr->data_size);
> +		if (info_hdr->data_size == sizeof(__u64)) {
> +			__u64 *max_page_count = (__u64 *)&info_hdr[1];

Why __u64 instead of u64?  Is this code shared with user space?

regards,
dan carpenter