[PATCH] thermal: cut the spaces when user sets policy

[PATCH] thermal: cut the spaces when user sets policy

[Andy Shevchenko]

Setting policy results in invalid value error.
	% echo "step_wise" > policy
	% echo: write error: Invalid argument

Need clean up of the buffer which "echo" may add based on the arguments, before
comparing aganist list of governor names.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reported-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/thermal/thermal_core.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index d755440..a637be5 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -33,6 +33,7 @@
 #include <linux/idr.h>
 #include <linux/thermal.h>
 #include <linux/reboot.h>
+#include <linux/string.h>
 #include <net/netlink.h>
 #include <net/genetlink.h>
 
@@ -716,7 +717,7 @@ policy_store(struct device *dev, struct device_attribute *attr,
 
 	mutex_lock(&thermal_governor_lock);
 
-	gov = __find_governor(buf);
+	gov = __find_governor(strim(buf));
 	if (!gov)
 		goto exit;
 
-- 
1.8.2.rc0.22.gb3600c3

Re: [PATCH] thermal: cut the spaces when user sets policy

[Eduardo Valentin]

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Andy,

On 03-05-2013 09:52, Andy Shevchenko wrote:
> Setting policy results in invalid value error.
> 	% echo "step_wise" > policy
> 	% echo: write error: Invalid argument
> 
> Need clean up of the buffer which "echo" may add based on the arguments, before
> comparing aganist list of governor names.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Reported-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
> ---
>  drivers/thermal/thermal_core.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index d755440..a637be5 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -33,6 +33,7 @@
>  #include <linux/idr.h>
>  #include <linux/thermal.h>
>  #include <linux/reboot.h>
> +#include <linux/string.h>
>  #include <net/netlink.h>
>  #include <net/genetlink.h>
>  
> @@ -716,7 +717,7 @@ policy_store(struct device *dev, struct device_attribute *attr,
>  
>  	mutex_lock(&thermal_governor_lock);
>  
> -	gov = __find_governor(buf);
> +	gov = __find_governor(strim(buf));

I am much happier with this approach, much cleaner and does the job. On
the other hand, this patch introduces a compilation warning that we want
to avoid:
drivers/thermal/thermal_sys.c: In function 'policy_store':
drivers/thermal/thermal_sys.c:708: warning: passing argument 1 of
'strim' discards qualifiers from pointer target type
include/linux/string.h:63: note: expected 'char *' but argument is of
type 'const char *'



>  	if (!gov)
>  		goto exit;
>  
> 



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Re: [PATCH] thermal: cut the spaces when user sets policy

[Andy Shevchenko]

On Fri, 2013-05-03 at 11:33 -0400, Eduardo Valentin wrote: 
> On 03-05-2013 09:52, Andy Shevchenko wrote:
> > Setting policy results in invalid value error.
> > 	% echo "step_wise" > policy
> > 	% echo: write error: Invalid argument
> > 
> > Need clean up of the buffer which "echo" may add based on the arguments, before
> > comparing aganist list of governor names.

> > @@ -716,7 +717,7 @@ policy_store(struct device *dev, struct device_attribute *attr,
> >  
> >  	mutex_lock(&thermal_governor_lock);
> >  
> > -	gov = __find_governor(buf);
> > +	gov = __find_governor(strim(buf));
> 
> I am much happier with this approach, much cleaner and does the job. On
> the other hand, this patch introduces a compilation warning that we want
> to avoid:
> drivers/thermal/thermal_sys.c: In function 'policy_store':
> drivers/thermal/thermal_sys.c:708: warning: passing argument 1 of
> 'strim' discards qualifiers from pointer target type
> include/linux/string.h:63: note: expected 'char *' but argument is of
> type 'const char *'
> 

Oops.
What about introduce temporary variable and pass it as a parameter?
It seems explicit casting looks not good, though it makes the job.


-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy