Re: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper

Re: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper

[kernel test robot]

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
In-Reply-To: <20241206111629.3521865-2-shaojijie@huawei.com>
References: <20241206111629.3521865-2-shaojijie@huawei.com>
TO: Jijie Shao <shaojijie@huawei.com>
TO: davem@davemloft.net
TO: edumazet@google.com
TO: kuba@kernel.org
TO: pabeni@redhat.com
TO: andrew+netdev@lunn.ch
TO: horms@kernel.org
TO: gregkh@linuxfoundation.org
CC: shenjian15@huawei.com
CC: wangpeiyang1@huawei.com
CC: liuyonglong@huawei.com
CC: chenhao418@huawei.com
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CC: shaojijie@huawei.com
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Hi Jijie,

kernel test robot noticed the following build warnings:

[auto build test WARNING on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Jijie-Shao/debugfs-Add-debugfs_create_devm_dir-helper/20241206-192734
base:   net-next/main
patch link:    https://lore.kernel.org/r/20241206111629.3521865-2-shaojijie%40huawei.com
patch subject: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper
:::::: branch date: 20 hours ago
:::::: commit date: 20 hours ago
config: i386-randconfig-141-20241206 (https://download.01.org/0day-ci/archive/20241207/202412071523.XnSXmPPZ-lkp@intel.com/config)
compiler: clang version 19.1.3 (https://github.com/llvm/llvm-project ab51eccf88f5321e7c60591c5546b254b6afab99)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Closes: https://lore.kernel.org/r/202412071523.XnSXmPPZ-lkp@intel.com/

smatch warnings:
fs/debugfs/inode.c:643 debugfs_create_devm_dir() warn: unchecked 'ERR_PTR'

vim +/ERR_PTR +643 fs/debugfs/inode.c

d44644eefac450 Jijie Shao 2024-12-06  619  
d44644eefac450 Jijie Shao 2024-12-06  620  /**
d44644eefac450 Jijie Shao 2024-12-06  621   * debugfs_create_devm_dir - Managed debugfs_create_dir()
d44644eefac450 Jijie Shao 2024-12-06  622   * @dev: Device that owns the action
d44644eefac450 Jijie Shao 2024-12-06  623   * @name: a pointer to a string containing the name of the directory to
d44644eefac450 Jijie Shao 2024-12-06  624   *        create.
d44644eefac450 Jijie Shao 2024-12-06  625   * @parent: a pointer to the parent dentry for this file.  This should be a
d44644eefac450 Jijie Shao 2024-12-06  626   *          directory dentry if set.  If this parameter is NULL, then the
d44644eefac450 Jijie Shao 2024-12-06  627   *          directory will be created in the root of the debugfs filesystem.
d44644eefac450 Jijie Shao 2024-12-06  628   * Managed debugfs_create_dir(). dentry will automatically be remove on
d44644eefac450 Jijie Shao 2024-12-06  629   * driver detach.
d44644eefac450 Jijie Shao 2024-12-06  630   */
d44644eefac450 Jijie Shao 2024-12-06  631  struct dentry *debugfs_create_devm_dir(struct device *dev, const char *name,
d44644eefac450 Jijie Shao 2024-12-06  632  				       struct dentry *parent)
d44644eefac450 Jijie Shao 2024-12-06  633  {
d44644eefac450 Jijie Shao 2024-12-06  634  	struct dentry *dentry;
d44644eefac450 Jijie Shao 2024-12-06  635  	int ret;
d44644eefac450 Jijie Shao 2024-12-06  636  
d44644eefac450 Jijie Shao 2024-12-06  637  	dentry = debugfs_create_dir(name, parent);
d44644eefac450 Jijie Shao 2024-12-06  638  	if (IS_ERR(dentry))
d44644eefac450 Jijie Shao 2024-12-06  639  		return dentry;
d44644eefac450 Jijie Shao 2024-12-06  640  
d44644eefac450 Jijie Shao 2024-12-06  641  	ret = devm_add_action_or_reset(dev, debugfs_remove_devm, dentry);
d44644eefac450 Jijie Shao 2024-12-06  642  	if (ret)
d44644eefac450 Jijie Shao 2024-12-06 @643  		ERR_PTR(ret);
d44644eefac450 Jijie Shao 2024-12-06  644  
d44644eefac450 Jijie Shao 2024-12-06  645  	return dentry;
d44644eefac450 Jijie Shao 2024-12-06  646  }
d44644eefac450 Jijie Shao 2024-12-06  647  EXPORT_SYMBOL_GPL(debugfs_create_devm_dir);
d44644eefac450 Jijie Shao 2024-12-06  648  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

[PATCH V5 net-next 0/8] Support some features for the HIBMCGE driver

[Jijie Shao]

In this patch series, The HIBMCGE driver implements some functions
such as dump register, unicast MAC address filtering, debugfs and reset.

---
ChangeLog:
v4 -> v5:
  - Add debugfs_create_devm_dir() helper, suggested by Jakub.
  - Simplify reset logic by optimizing release and re-hold rtnl lock, suggested by Jakub.
  v4: https://lore.kernel.org/all/20241203150131.3139399-1-shaojijie@huawei.com/
v3 -> v4:
  - Support auto-neg pause, suggested by Andrew.
  v3: https://lore.kernel.org/all/20241111145558.1965325-1-shaojijie@huawei.com/
v2 -> v3:
  -  Not not dump in ethtool statistics which can be accessed via standard APIs,
     suggested by Jakub. The relevant patche is removed from this patch series,
     and the statistically relevant patches will be sent separately.
  v2: https://lore.kernel.org/all/20241026115740.633503-1-shaojijie@huawei.com/
v1 -> v2:
  - Remove debugfs file 'dev_specs' because the dump register
    does the same thing, suggested by Andrew.
  - Move 'tx timeout cnt' from debugfs to ethtool -S, suggested by Andrew.
  - Ignore the error code of the debugfs initialization failure, suggested by Andrew.
  - Add a new patch for debugfs file 'irq_info', suggested by Andrew.
  - Add somme comments for filtering, suggested by Andrew.
  - Not pass back ASCII text in dump register, suggested by Andrew.
  v1: https://lore.kernel.org/all/20241023134213.3359092-1-shaojijie@huawei.com/
---

Jijie Shao (8):
  debugfs: Add debugfs_create_devm_dir() helper
  net: hibmcge: Add debugfs supported in this module
  net: hibmcge: Add irq_info file to debugfs
  net: hibmcge: Add unicast frame filter supported in this module
  net: hibmcge: Add register dump supported in this module
  net: hibmcge: Add pauseparam supported in this module
  net: hibmcge: Add reset supported in this module
  net: hibmcge: Add nway_reset supported in this module

 .../net/ethernet/hisilicon/hibmcge/Makefile   |   3 +-
 .../ethernet/hisilicon/hibmcge/hbg_common.h   |  30 +++
 .../ethernet/hisilicon/hibmcge/hbg_debugfs.c  | 155 +++++++++++++
 .../ethernet/hisilicon/hibmcge/hbg_debugfs.h  |  12 +
 .../net/ethernet/hisilicon/hibmcge/hbg_err.c  | 137 +++++++++++
 .../net/ethernet/hisilicon/hibmcge/hbg_err.h  |  13 ++
 .../ethernet/hisilicon/hibmcge/hbg_ethtool.c  | 187 +++++++++++++++
 .../net/ethernet/hisilicon/hibmcge/hbg_hw.c   |  48 +++-
 .../net/ethernet/hisilicon/hibmcge/hbg_hw.h   |   6 +-
 .../net/ethernet/hisilicon/hibmcge/hbg_main.c | 212 ++++++++++++++++--
 .../net/ethernet/hisilicon/hibmcge/hbg_mdio.c |  15 ++
 .../net/ethernet/hisilicon/hibmcge/hbg_reg.h  |  39 ++++
 fs/debugfs/inode.c                            |  36 +++
 include/linux/debugfs.h                       |  10 +
 14 files changed, 875 insertions(+), 28 deletions(-)
 create mode 100644 drivers/net/ethernet/hisilicon/hibmcge/hbg_debugfs.c
 create mode 100644 drivers/net/ethernet/hisilicon/hibmcge/hbg_debugfs.h
 create mode 100644 drivers/net/ethernet/hisilicon/hibmcge/hbg_err.c
 create mode 100644 drivers/net/ethernet/hisilicon/hibmcge/hbg_err.h

-- 
2.33.0

[PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper

[Jijie Shao]

Add debugfs_create_devm_dir() helper

Signed-off-by: Jijie Shao <shaojijie@huawei.com>
---
 fs/debugfs/inode.c      | 36 ++++++++++++++++++++++++++++++++++++
 include/linux/debugfs.h | 10 ++++++++++
 2 files changed, 46 insertions(+)

diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 38a9c7eb97e6..f682c4952a27 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -610,6 +610,42 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
 }
 EXPORT_SYMBOL_GPL(debugfs_create_dir);
 
+static void debugfs_remove_devm(void *dentry_rwa)
+{
+	struct dentry *dentry = dentry_rwa;
+
+	debugfs_remove(dentry);
+}
+
+/**
+ * debugfs_create_devm_dir - Managed debugfs_create_dir()
+ * @dev: Device that owns the action
+ * @name: a pointer to a string containing the name of the directory to
+ *        create.
+ * @parent: a pointer to the parent dentry for this file.  This should be a
+ *          directory dentry if set.  If this parameter is NULL, then the
+ *          directory will be created in the root of the debugfs filesystem.
+ * Managed debugfs_create_dir(). dentry will automatically be remove on
+ * driver detach.
+ */
+struct dentry *debugfs_create_devm_dir(struct device *dev, const char *name,
+				       struct dentry *parent)
+{
+	struct dentry *dentry;
+	int ret;
+
+	dentry = debugfs_create_dir(name, parent);
+	if (IS_ERR(dentry))
+		return dentry;
+
+	ret = devm_add_action_or_reset(dev, debugfs_remove_devm, dentry);
+	if (ret)
+		ERR_PTR(ret);
+
+	return dentry;
+}
+EXPORT_SYMBOL_GPL(debugfs_create_devm_dir);
+
 /**
  * debugfs_create_automount - create automount point in the debugfs filesystem
  * @name: a pointer to a string containing the name of the file to create.
diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h
index 59444b495d49..19d8c322debe 100644
--- a/include/linux/debugfs.h
+++ b/include/linux/debugfs.h
@@ -139,6 +139,9 @@ void debugfs_create_file_size(const char *name, umode_t mode,
 
 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
 
+struct dentry *debugfs_create_devm_dir(struct device *dev, const char *name,
+				       struct dentry *parent);
+
 struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
 				      const char *dest);
 
@@ -286,6 +289,13 @@ static inline struct dentry *debugfs_create_dir(const char *name,
 	return ERR_PTR(-ENODEV);
 }
 
+static inline struct dentry *debugfs_create_devm_dir(struct device *dev,
+						     const char *name,
+						     struct dentry *parent)
+{
+	return ERR_PTR(-ENODEV);
+}
+
 static inline struct dentry *debugfs_create_symlink(const char *name,
 						    struct dentry *parent,
 						    const char *dest)
-- 
2.33.0

Re: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper

[Greg KH]

On Fri, Dec 06, 2024 at 07:16:22PM +0800, Jijie Shao wrote:
> Add debugfs_create_devm_dir() helper
> 
> Signed-off-by: Jijie Shao <shaojijie@huawei.com>
> ---
>  fs/debugfs/inode.c      | 36 ++++++++++++++++++++++++++++++++++++
>  include/linux/debugfs.h | 10 ++++++++++
>  2 files changed, 46 insertions(+)
> 
> diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
> index 38a9c7eb97e6..f682c4952a27 100644
> --- a/fs/debugfs/inode.c
> +++ b/fs/debugfs/inode.c
> @@ -610,6 +610,42 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
>  }
>  EXPORT_SYMBOL_GPL(debugfs_create_dir);
>  
> +static void debugfs_remove_devm(void *dentry_rwa)
> +{
> +	struct dentry *dentry = dentry_rwa;
> +
> +	debugfs_remove(dentry);
> +}
> +
> +/**
> + * debugfs_create_devm_dir - Managed debugfs_create_dir()
> + * @dev: Device that owns the action
> + * @name: a pointer to a string containing the name of the directory to
> + *        create.
> + * @parent: a pointer to the parent dentry for this file.  This should be a
> + *          directory dentry if set.  If this parameter is NULL, then the
> + *          directory will be created in the root of the debugfs filesystem.
> + * Managed debugfs_create_dir(). dentry will automatically be remove on
> + * driver detach.
> + */
> +struct dentry *debugfs_create_devm_dir(struct device *dev, const char *name,
> +				       struct dentry *parent)
> +{
> +	struct dentry *dentry;
> +	int ret;
> +
> +	dentry = debugfs_create_dir(name, parent);
> +	if (IS_ERR(dentry))
> +		return dentry;
> +
> +	ret = devm_add_action_or_reset(dev, debugfs_remove_devm, dentry);
> +	if (ret)
> +		ERR_PTR(ret);

You don't clean up the directory you created if this failed?  Why not?

thanks,

greg k-h

Re: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper

[Jijie Shao]

on 2024/12/6 19:40, Greg KH wrote:
> On Fri, Dec 06, 2024 at 07:16:22PM +0800, Jijie Shao wrote:
>> Add debugfs_create_devm_dir() helper
>>
>> Signed-off-by: Jijie Shao <shaojijie@huawei.com>
>> ---
>>   fs/debugfs/inode.c      | 36 ++++++++++++++++++++++++++++++++++++
>>   include/linux/debugfs.h | 10 ++++++++++
>>   2 files changed, 46 insertions(+)
>>
>> diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
>> index 38a9c7eb97e6..f682c4952a27 100644
>> --- a/fs/debugfs/inode.c
>> +++ b/fs/debugfs/inode.c
>> @@ -610,6 +610,42 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
>>   }
>>   EXPORT_SYMBOL_GPL(debugfs_create_dir);
>>   
>> +static void debugfs_remove_devm(void *dentry_rwa)
>> +{
>> +	struct dentry *dentry = dentry_rwa;
>> +
>> +	debugfs_remove(dentry);
>> +}
>> +
>> +/**
>> + * debugfs_create_devm_dir - Managed debugfs_create_dir()
>> + * @dev: Device that owns the action
>> + * @name: a pointer to a string containing the name of the directory to
>> + *        create.
>> + * @parent: a pointer to the parent dentry for this file.  This should be a
>> + *          directory dentry if set.  If this parameter is NULL, then the
>> + *          directory will be created in the root of the debugfs filesystem.
>> + * Managed debugfs_create_dir(). dentry will automatically be remove on
>> + * driver detach.
>> + */
>> +struct dentry *debugfs_create_devm_dir(struct device *dev, const char *name,
>> +				       struct dentry *parent)
>> +{
>> +	struct dentry *dentry;
>> +	int ret;
>> +
>> +	dentry = debugfs_create_dir(name, parent);
>> +	if (IS_ERR(dentry))
>> +		return dentry;
>> +
>> +	ret = devm_add_action_or_reset(dev, debugfs_remove_devm, dentry);
>> +	if (ret)
>> +		ERR_PTR(ret);
> You don't clean up the directory you created if this failed?  Why not?

Don't need to clean up.
in devm_add_action_or_reset(), if failed, will call action: debugfs_remove_devm(),
So, not clean up again.

#define devm_add_action_or_reset(dev, action, data) \
	__devm_add_action_or_reset(dev, action, data, #action)

static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *),
					     void *data, const char *name)
{
	int ret;

	ret = __devm_add_action(dev, action, data, name);
	if (ret)
		action(data);

	return ret;
}

But there's a problem with this, I missed return.
I will add return in v6.

Thanks,
Jijie Shao

Re: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper

[Greg KH]

On Mon, Dec 09, 2024 at 09:02:10AM +0800, Jijie Shao wrote:
> 
> on 2024/12/6 19:40, Greg KH wrote:
> > On Fri, Dec 06, 2024 at 07:16:22PM +0800, Jijie Shao wrote:
> > > Add debugfs_create_devm_dir() helper
> > > 
> > > Signed-off-by: Jijie Shao <shaojijie@huawei.com>
> > > ---
> > >   fs/debugfs/inode.c      | 36 ++++++++++++++++++++++++++++++++++++
> > >   include/linux/debugfs.h | 10 ++++++++++
> > >   2 files changed, 46 insertions(+)
> > > 
> > > diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
> > > index 38a9c7eb97e6..f682c4952a27 100644
> > > --- a/fs/debugfs/inode.c
> > > +++ b/fs/debugfs/inode.c
> > > @@ -610,6 +610,42 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
> > >   }
> > >   EXPORT_SYMBOL_GPL(debugfs_create_dir);
> > > +static void debugfs_remove_devm(void *dentry_rwa)
> > > +{
> > > +	struct dentry *dentry = dentry_rwa;
> > > +
> > > +	debugfs_remove(dentry);
> > > +}
> > > +
> > > +/**
> > > + * debugfs_create_devm_dir - Managed debugfs_create_dir()
> > > + * @dev: Device that owns the action
> > > + * @name: a pointer to a string containing the name of the directory to
> > > + *        create.
> > > + * @parent: a pointer to the parent dentry for this file.  This should be a
> > > + *          directory dentry if set.  If this parameter is NULL, then the
> > > + *          directory will be created in the root of the debugfs filesystem.
> > > + * Managed debugfs_create_dir(). dentry will automatically be remove on
> > > + * driver detach.
> > > + */
> > > +struct dentry *debugfs_create_devm_dir(struct device *dev, const char *name,
> > > +				       struct dentry *parent)
> > > +{
> > > +	struct dentry *dentry;
> > > +	int ret;
> > > +
> > > +	dentry = debugfs_create_dir(name, parent);
> > > +	if (IS_ERR(dentry))
> > > +		return dentry;
> > > +
> > > +	ret = devm_add_action_or_reset(dev, debugfs_remove_devm, dentry);
> > > +	if (ret)
> > > +		ERR_PTR(ret);
> > You don't clean up the directory you created if this failed?  Why not?
> 
> Don't need to clean up.
> in devm_add_action_or_reset(), if failed, will call action: debugfs_remove_devm(),
> So, not clean up again.
> 
> #define devm_add_action_or_reset(dev, action, data) \
> 	__devm_add_action_or_reset(dev, action, data, #action)
> 
> static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *),
> 					     void *data, const char *name)
> {
> 	int ret;
> 
> 	ret = __devm_add_action(dev, action, data, name);
> 	if (ret)
> 		action(data);
> 
> 	return ret;
> }
> 
> But there's a problem with this, I missed return.
> I will add return in v6.

As this did not even compile, how did you test any of this?

I'm now loath to add this at all, please let's just keep this "open
coded" in your driver for now until there are multiple users that need
this and then convert them all to use the function when you add it.

thanks,

greg k-h

Re: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper

[Jijie Shao]

on 2024/12/9 14:31, Greg KH wrote:
> On Mon, Dec 09, 2024 at 09:02:10AM +0800, Jijie Shao wrote:
>> on 2024/12/6 19:40, Greg KH wrote:
>>> On Fri, Dec 06, 2024 at 07:16:22PM +0800, Jijie Shao wrote:
>>>> Add debugfs_create_devm_dir() helper
>>>>
>>>> Signed-off-by: Jijie Shao <shaojijie@huawei.com>
>>>> ---
>>>>    fs/debugfs/inode.c      | 36 ++++++++++++++++++++++++++++++++++++
>>>>    include/linux/debugfs.h | 10 ++++++++++
>>>>    2 files changed, 46 insertions(+)
>>>>
>>>> diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
>>>> index 38a9c7eb97e6..f682c4952a27 100644
>>>> --- a/fs/debugfs/inode.c
>>>> +++ b/fs/debugfs/inode.c
>>>> @@ -610,6 +610,42 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
>>>>    }
>>>>    EXPORT_SYMBOL_GPL(debugfs_create_dir);
>>>> +static void debugfs_remove_devm(void *dentry_rwa)
>>>> +{
>>>> +	struct dentry *dentry = dentry_rwa;
>>>> +
>>>> +	debugfs_remove(dentry);
>>>> +}
>>>> +
>>>> +/**
>>>> + * debugfs_create_devm_dir - Managed debugfs_create_dir()
>>>> + * @dev: Device that owns the action
>>>> + * @name: a pointer to a string containing the name of the directory to
>>>> + *        create.
>>>> + * @parent: a pointer to the parent dentry for this file.  This should be a
>>>> + *          directory dentry if set.  If this parameter is NULL, then the
>>>> + *          directory will be created in the root of the debugfs filesystem.
>>>> + * Managed debugfs_create_dir(). dentry will automatically be remove on
>>>> + * driver detach.
>>>> + */
>>>> +struct dentry *debugfs_create_devm_dir(struct device *dev, const char *name,
>>>> +				       struct dentry *parent)
>>>> +{
>>>> +	struct dentry *dentry;
>>>> +	int ret;
>>>> +
>>>> +	dentry = debugfs_create_dir(name, parent);
>>>> +	if (IS_ERR(dentry))
>>>> +		return dentry;
>>>> +
>>>> +	ret = devm_add_action_or_reset(dev, debugfs_remove_devm, dentry);
>>>> +	if (ret)
>>>> +		ERR_PTR(ret);
>>> You don't clean up the directory you created if this failed?  Why not?
>> Don't need to clean up.
>> in devm_add_action_or_reset(), if failed, will call action: debugfs_remove_devm(),
>> So, not clean up again.
>>
>> #define devm_add_action_or_reset(dev, action, data) \
>> 	__devm_add_action_or_reset(dev, action, data, #action)
>>
>> static inline int __devm_add_action_or_reset(struct device *dev, void (*action)(void *),
>> 					     void *data, const char *name)
>> {
>> 	int ret;
>>
>> 	ret = __devm_add_action(dev, action, data, name);
>> 	if (ret)
>> 		action(data);
>>
>> 	return ret;
>> }
>>
>> But there's a problem with this, I missed return.
>> I will add return in v6.
> As this did not even compile, how did you test any of this?
>
> I'm now loath to add this at all, please let's just keep this "open
> coded" in your driver for now until there are multiple users that need
> this and then convert them all to use the function when you add it.
>
> thanks,
>
> greg k-h

I've tested and it's ok,

But, there is a warning(warn_unused_result)..
My test command does not check warning other than the hibmcge driver.
This was caused by my carelessness. I'm very sorry.

I've looked at other driver codes, and quite a few others have similar codes.
As you suggest, this patchset still uses open code in next version.
In the future, I will try to send a new independent patchset to introduce it.

Thanks,
Jijie Shao

Re: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper

[kernel test robot]

Hi Jijie,

kernel test robot noticed the following build warnings:

[auto build test WARNING on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Jijie-Shao/debugfs-Add-debugfs_create_devm_dir-helper/20241206-192734
base:   net-next/main
patch link:    https://lore.kernel.org/r/20241206111629.3521865-2-shaojijie%40huawei.com
patch subject: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper
config: powerpc-ebony_defconfig (https://download.01.org/0day-ci/archive/20241206/202412062221.GPVtNG5v-lkp@intel.com/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241206/202412062221.GPVtNG5v-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202412062221.GPVtNG5v-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> fs/debugfs/inode.c:643:3: warning: ignoring return value of function declared with 'warn_unused_result' attribute [-Wunused-result]
     643 |                 ERR_PTR(ret);
         |                 ^~~~~~~ ~~~
   1 warning generated.


vim +/warn_unused_result +643 fs/debugfs/inode.c

   619	
   620	/**
   621	 * debugfs_create_devm_dir - Managed debugfs_create_dir()
   622	 * @dev: Device that owns the action
   623	 * @name: a pointer to a string containing the name of the directory to
   624	 *        create.
   625	 * @parent: a pointer to the parent dentry for this file.  This should be a
   626	 *          directory dentry if set.  If this parameter is NULL, then the
   627	 *          directory will be created in the root of the debugfs filesystem.
   628	 * Managed debugfs_create_dir(). dentry will automatically be remove on
   629	 * driver detach.
   630	 */
   631	struct dentry *debugfs_create_devm_dir(struct device *dev, const char *name,
   632					       struct dentry *parent)
   633	{
   634		struct dentry *dentry;
   635		int ret;
   636	
   637		dentry = debugfs_create_dir(name, parent);
   638		if (IS_ERR(dentry))
   639			return dentry;
   640	
   641		ret = devm_add_action_or_reset(dev, debugfs_remove_devm, dentry);
   642		if (ret)
 > 643			ERR_PTR(ret);
   644	
   645		return dentry;
   646	}
   647	EXPORT_SYMBOL_GPL(debugfs_create_devm_dir);
   648	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper

[kernel test robot]

Hi Jijie,

kernel test robot noticed the following build warnings:

[auto build test WARNING on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Jijie-Shao/debugfs-Add-debugfs_create_devm_dir-helper/20241206-192734
base:   net-next/main
patch link:    https://lore.kernel.org/r/20241206111629.3521865-2-shaojijie%40huawei.com
patch subject: [PATCH V5 net-next 1/8] debugfs: Add debugfs_create_devm_dir() helper
config: x86_64-buildonly-randconfig-003-20241206 (https://download.01.org/0day-ci/archive/20241207/202412070055.uUO1oKY8-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241207/202412070055.uUO1oKY8-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202412070055.uUO1oKY8-lkp@intel.com/

All warnings (new ones prefixed by >>):

   fs/debugfs/inode.c: In function 'debugfs_create_devm_dir':
>> fs/debugfs/inode.c:643:17: warning: ignoring return value of 'ERR_PTR' declared with attribute 'warn_unused_result' [-Wunused-result]
     643 |                 ERR_PTR(ret);
         |                 ^~~~~~~~~~~~


vim +643 fs/debugfs/inode.c

   619	
   620	/**
   621	 * debugfs_create_devm_dir - Managed debugfs_create_dir()
   622	 * @dev: Device that owns the action
   623	 * @name: a pointer to a string containing the name of the directory to
   624	 *        create.
   625	 * @parent: a pointer to the parent dentry for this file.  This should be a
   626	 *          directory dentry if set.  If this parameter is NULL, then the
   627	 *          directory will be created in the root of the debugfs filesystem.
   628	 * Managed debugfs_create_dir(). dentry will automatically be remove on
   629	 * driver detach.
   630	 */
   631	struct dentry *debugfs_create_devm_dir(struct device *dev, const char *name,
   632					       struct dentry *parent)
   633	{
   634		struct dentry *dentry;
   635		int ret;
   636	
   637		dentry = debugfs_create_dir(name, parent);
   638		if (IS_ERR(dentry))
   639			return dentry;
   640	
   641		ret = devm_add_action_or_reset(dev, debugfs_remove_devm, dentry);
   642		if (ret)
 > 643			ERR_PTR(ret);
   644	
   645		return dentry;
   646	}
   647	EXPORT_SYMBOL_GPL(debugfs_create_devm_dir);
   648	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki