Re: [PATCH] block: sysfs fix mismatched queue_var_{store,show} in 64bit kernel

[Johannes Weiner <hannes@cmpxchg.org>]

On Tue, Jul 14, 2009 at 07:56:58PM +0800, Xiaotian Feng wrote:
> In blk-sysfs.c, queue_var_store uses unsigned long to store data,
> but queue_var_show uses unsigned int to show data. This causes,
> 
> 	# echo 70000000000 > /sys/block/<dev>/queue/read_ahead_kb
> 	# cat /sys/block/<dev>/queue/read_ahead_kb => get wrong value
> 
> Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
> ---
>  block/blk-sysfs.c |   13 +++++++------
>  1 files changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
> index b1cd040..e177eb3 100644
> --- a/block/blk-sysfs.c
> +++ b/block/blk-sysfs.c
> @@ -16,9 +16,9 @@ struct queue_sysfs_entry {
>  };
>  
>  static ssize_t
> -queue_var_show(unsigned int var, char *page)
> +queue_var_show(unsigned long var, char *page)
>  {
> -	return sprintf(page, "%d\n", var);
> +	return sprintf(page, "lu\n", var);

%lu, I guess?