[PATCH 1/2] usb: typec: tcpm: free log buf memory when remove debug file

[PATCH 1/2] usb: typec: tcpm: free log buf memory when remove debug file

[jun.li]

From: Li Jun <jun.li@nxp.com>

The logbuffer memory should be freed when remove debug file.

Cc: stable@vger.kernel.org # v4.15+
Fixes: 4b4e02c83167 ("typec: tcpm: Move out of staging")
Signed-off-by: Li Jun <jun.li@nxp.com>
---
 drivers/usb/typec/tcpm/tcpm.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index fba32d8..1249d8e 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -586,6 +586,15 @@ static void tcpm_debugfs_init(struct tcpm_port *port)
 
 static void tcpm_debugfs_exit(struct tcpm_port *port)
 {
+	int i;
+
+	mutex_lock(&port->logbuffer_lock);
+	for (i = 0; i < LOG_BUFFER_ENTRIES; i++) {
+		kfree(port->logbuffer[i]);
+		port->logbuffer[i] = NULL;
+	}
+	mutex_unlock(&port->logbuffer_lock);
+
 	debugfs_remove(port->dentry);
 }
 
-- 
2.7.4

[PATCH 2/2] usb: typec: tcpm: remove tcpm dir if no children

[jun.li]

From: Li Jun <jun.li@nxp.com>

If config tcpm as module, module unload will not remove tcpm dir,
then the next module load will have problem: the rootdir is NULL
but tcpm dir is still there, so tcpm_debugfs_init() will create
tcpm dir again with failure, fix it by remove the tcpm dir if no
children.

Cc: stable@vger.kernel.org # v4.15+
Fixes: 4b4e02c83167 ("typec: tcpm: Move out of staging")
Signed-off-by: Li Jun <jun.li@nxp.com>
---
 drivers/usb/typec/tcpm/tcpm.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 1249d8e..86e4552 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -596,6 +596,10 @@ static void tcpm_debugfs_exit(struct tcpm_port *port)
 	mutex_unlock(&port->logbuffer_lock);
 
 	debugfs_remove(port->dentry);
+	if (list_empty(&rootdir->d_subdirs)) {
+		debugfs_remove(rootdir);
+		rootdir = NULL;
+	}
 }
 
 #else
-- 
2.7.4

Re: [PATCH 1/2] usb: typec: tcpm: free log buf memory when remove debug file

[Guenter Roeck]

On 7/17/19 1:06 AM, jun.li@nxp.com wrote:
> From: Li Jun <jun.li@nxp.com>
> 
> The logbuffer memory should be freed when remove debug file.
> 
> Cc: stable@vger.kernel.org # v4.15+
> Fixes: 4b4e02c83167 ("typec: tcpm: Move out of staging")
> Signed-off-by: Li Jun <jun.li@nxp.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>   drivers/usb/typec/tcpm/tcpm.c | 9 +++++++++
>   1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index fba32d8..1249d8e 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -586,6 +586,15 @@ static void tcpm_debugfs_init(struct tcpm_port *port)
>   
>   static void tcpm_debugfs_exit(struct tcpm_port *port)
>   {
> +	int i;
> +
> +	mutex_lock(&port->logbuffer_lock);
> +	for (i = 0; i < LOG_BUFFER_ENTRIES; i++) {
> +		kfree(port->logbuffer[i]);
> +		port->logbuffer[i] = NULL;
> +	}
> +	mutex_unlock(&port->logbuffer_lock);
> +
>   	debugfs_remove(port->dentry);
>   }
>   
> 

Re: [PATCH 2/2] usb: typec: tcpm: remove tcpm dir if no children

[Guenter Roeck]

On 7/17/19 1:06 AM, jun.li@nxp.com wrote:
> From: Li Jun <jun.li@nxp.com>
> 
> If config tcpm as module, module unload will not remove tcpm dir,
> then the next module load will have problem: the rootdir is NULL
> but tcpm dir is still there, so tcpm_debugfs_init() will create
> tcpm dir again with failure, fix it by remove the tcpm dir if no
> children.
> 
> Cc: stable@vger.kernel.org # v4.15+
> Fixes: 4b4e02c83167 ("typec: tcpm: Move out of staging")
> Signed-off-by: Li Jun <jun.li@nxp.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>   drivers/usb/typec/tcpm/tcpm.c | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 1249d8e..86e4552 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -596,6 +596,10 @@ static void tcpm_debugfs_exit(struct tcpm_port *port)
>   	mutex_unlock(&port->logbuffer_lock);
>   
>   	debugfs_remove(port->dentry);
> +	if (list_empty(&rootdir->d_subdirs)) {
> +		debugfs_remove(rootdir);
> +		rootdir = NULL;
> +	}
>   }
>   
>   #else
>