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Subject: Re: [PATCH 1/1] debugfs: use IS_ERR to check for error
To:     Greg KH <gregkh@linuxfoundation.org>,
        Nirmoy Das <nirmoy.das@amd.com>
Cc:     rafael@kernel.org, linux-kernel@vger.kernel.org
References: <20210902102917.2233-1-nirmoy.das@amd.com>
 <YTCpuo00wM7jGSIc@kroah.com>
From:   =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>
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Date:   Thu, 2 Sep 2021 14:03:12 +0200
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Am 02.09.21 um 12:38 schrieb Greg KH:
> On Thu, Sep 02, 2021 at 12:29:17PM +0200, Nirmoy Das wrote:
>> debugfs_create_file() returns encoded error so
>> use IS_ERR for checking return value.
>>
>> References: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitlab.freedesktop.org%2Fdrm%2Famd%2F-%2Fissues%2F1686&amp;data=04%7C01%7CChristian.Koenig%40amd.com%7C82691bea64d3491fe86008d96dfddc60%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637661759378883940%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=Xs4xnihnMzNvl%2BSEEpCcWkdvMaDw1Ofvekn%2Fnvz1mM8%3D&amp;reserved=0
>> Signed-off-by: Nirmoy Das <nirmoy.das@amd.com>
>> ---
>>   fs/debugfs/inode.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
>> index 8129a430d789..2f117c57160d 100644
>> --- a/fs/debugfs/inode.c
>> +++ b/fs/debugfs/inode.c
>> @@ -528,7 +528,7 @@ void debugfs_create_file_size(const char *name, umode_t mode,
>>   {
>>   	struct dentry *de = debugfs_create_file(name, mode, parent, data, fops);
>>   
>> -	if (de)
>> +	if (!IS_ERR(de))
>>   		d_inode(de)->i_size = file_size;
>>   }
>>   EXPORT_SYMBOL_GPL(debugfs_create_file_size);
>> -- 
>> 2.32.0
>>
> Ah, good catch, I'll queue this up after 5.15-rc1 is out, thanks!

Thinking more about this if I'm not completely mistaken 
debugfs_create_file() returns -ENODEV when debugfs is disabled and NULL 
on any other error.

So this needs to be IS_ERR_OR_NULL().

Regards,
Christian.

>
> greg k-h