[PATCH RESEND v2] coresight: etm4x: Fix mis-usage of nr_resource in sysfs interface

[Jonathan Zhou]

On 16/09/2020 00:42, Mathieu Poirier wrote:
> On Tue, Sep 15, 2020 at 10:53:57AM +0800, Jonathan Zhou wrote:
>> The member @nr_resource represents how many resource selector pairs,
>> and the pair 0 is always implemented and reserved.
>> So let's multiply by 2 when resetting the seletor configuration.
>> And also update the validation of the input @idx.
>>
>> Cc: Mathieu Poirier <mathieu.poirier at linaro.org>
>> Cc: Suzuki K Poulose <suzuki.poulose at arm.com>
>> Cc: Mike Leach <mike.leach at linaro.org>
>> Cc: Shaokun Zhang <zhangshaokun at hisilicon.com>
>> Cc: lizixian at hisilicon.com
>> Signed-off-by: Jonathan Zhou <jonathan.zhouwen at huawei.com>
>> ---
>> ChangeLog in v2:
>>     * Address Mathieu's comments.
>>
>>  drivers/hwtracing/coresight/coresight-etm4x-sysfs.c | 9 ++++++---
>>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> You send me two identical patches on the same day - the only difference was the
> RESEND had an capital 'f' in "Fix".  That's the one I applied.
> 
Very sorry for sending this patch twice. I saw your revise for my
previous patch, so I am trying to keep the latter patches in line with
the norms.

Regards.
Jonathan

> Thanks,
> Mathieu
> 
> 
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
>> index b673e738bc9a..e4f1f659000d 100644
>> --- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
>> +++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
>> @@ -236,7 +236,7 @@ static ssize_t reset_store(struct device *dev,
>>  	}
>>  
>>  	config->res_idx = 0x0;
>> -	for (i = 0; i < drvdata->nr_resource; i++)
>> +	for (i = 2; i < 2 * drvdata->nr_resource; i++)
>>  		config->res_ctrl[i] = 0x0;
>>  
>>  	config->ss_idx = 0x0;
>> @@ -1663,8 +1663,11 @@ static ssize_t res_idx_store(struct device *dev,
>>  
>>  	if (kstrtoul(buf, 16, &val))
>>  		return -EINVAL;
>> -	/* Resource selector pair 0 is always implemented and reserved */
>> -	if ((val == 0) || (val >= drvdata->nr_resource))
>> +	/*
>> +	 * Resource selector pair 0 is always implemented and reserved,
>> +	 * namely an idx with 0 and 1 is illegal.
>> +	 */
>> +	if ((val < 2) || (val >= 2 * drvdata->nr_resource))
>>  		return -EINVAL;
>>  
>>  	/*
>> -- 
>> 1.9.1
>>
> .
>