[PATCH v4] drm/connector: hdmi: Fix writing Dynamic Range Mastering infoframes

[PATCH v4] drm/connector: hdmi: Fix writing Dynamic Range Mastering infoframes

[Derek Foreman]

The largest infoframe we create is the DRM (Dynamic Range Mastering)
infoframe which is 26 bytes + a 4 byte header, for a total of 30
bytes.

With HDMI_MAX_INFOFRAME_SIZE set to 29 bytes, as it is now, we
allocate too little space to pack a DRM infoframe in
write_device_infoframe(), leading to an ENOSPC return from
hdmi_infoframe_pack(), and never calling the connector's
write_infoframe() vfunc.

Instead of having HDMI_MAX_INFOFRAME_SIZE defined in two places,
replace HDMI_MAX_INFOFRAME_SIZE with HDMI_INFOFRAME_SIZE(MAX) and make
MAX 27 bytes - which is defined by the HDMI specification to be the
largest infoframe payload.

Fixes: f378b77227bc ("drm/connector: hdmi: Add Infoframes generation")
Fixes: c602e4959a0c ("drm/connector: hdmi: Create Infoframe DebugFS entries")

Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
---
 drivers/gpu/drm/display/drm_hdmi_state_helper.c | 4 +---
 drivers/gpu/drm/drm_debugfs.c                   | 4 +---
 include/linux/hdmi.h                            | 9 +++++++++
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
index 7854820089ec..feb7a3a75981 100644
--- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c
+++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
@@ -521,8 +521,6 @@ int drm_atomic_helper_connector_hdmi_check(struct drm_connector *connector,
 }
 EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_check);
 
-#define HDMI_MAX_INFOFRAME_SIZE		29
-
 static int clear_device_infoframe(struct drm_connector *connector,
 				  enum hdmi_infoframe_type type)
 {
@@ -563,7 +561,7 @@ static int write_device_infoframe(struct drm_connector *connector,
 {
 	const struct drm_connector_hdmi_funcs *funcs = connector->hdmi.funcs;
 	struct drm_device *dev = connector->dev;
-	u8 buffer[HDMI_MAX_INFOFRAME_SIZE];
+	u8 buffer[HDMI_INFOFRAME_SIZE(MAX)];
 	int ret;
 	int len;
 
diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
index 6b239a24f1df..9d3e6dd68810 100644
--- a/drivers/gpu/drm/drm_debugfs.c
+++ b/drivers/gpu/drm/drm_debugfs.c
@@ -520,8 +520,6 @@ static const struct file_operations drm_connector_fops = {
 	.write = connector_write
 };
 
-#define HDMI_MAX_INFOFRAME_SIZE		29
-
 static ssize_t
 audio_infoframe_read(struct file *filp, char __user *ubuf, size_t count, loff_t *ppos)
 {
@@ -579,7 +577,7 @@ static ssize_t _f##_read_infoframe(struct file *filp, \
 	struct drm_connector *connector; \
 	union hdmi_infoframe *frame; \
 	struct drm_device *dev; \
-	u8 buf[HDMI_MAX_INFOFRAME_SIZE]; \
+	u8 buf[HDMI_INFOFRAME_SIZE(MAX)]; \
 	ssize_t len = 0; \
 	\
 	connector = filp->private_data; \
diff --git a/include/linux/hdmi.h b/include/linux/hdmi.h
index 3bb87bf6bc65..455f855bc084 100644
--- a/include/linux/hdmi.h
+++ b/include/linux/hdmi.h
@@ -59,6 +59,15 @@ enum hdmi_infoframe_type {
 #define HDMI_DRM_INFOFRAME_SIZE    26
 #define HDMI_VENDOR_INFOFRAME_SIZE  4
 
+/*
+ * HDMI 1.3a table 5-14 states that the largest InfoFrame_length is 27,
+ * not including the packet header or checksum byte. We include the
+ * checksum byte in HDMI_INFOFRAME_HEADER_SIZE, so this should allow
+ * HDMI_INFOFRAME_SIZE(MAX) to be the largest buffer we could ever need
+ * for any HDMI infoframe.
+ */
+#define HDMI_MAX_INFOFRAME_SIZE    27
+
 #define HDMI_INFOFRAME_SIZE(type)	\
 	(HDMI_INFOFRAME_HEADER_SIZE + HDMI_ ## type ## _INFOFRAME_SIZE)
 
-- 
2.45.2

Re: [PATCH v4] drm/connector: hdmi: Fix writing Dynamic Range Mastering infoframes

[Maxime Ripard]

On Tue, 27 Aug 2024 11:39:04 -0500, Derek Foreman wrote:
> The largest infoframe we create is the DRM (Dynamic Range Mastering)
> infoframe which is 26 bytes + a 4 byte header, for a total of 30
> bytes.
> 
> With HDMI_MAX_INFOFRAME_SIZE set to 29 bytes, as it is now, we
> 
> [ ... ]

Acked-by: Maxime Ripard <mripard@kernel.org>

Thanks!
Maxime

Re: [PATCH v4] drm/connector: hdmi: Fix writing Dynamic Range Mastering infoframes

[Jani Nikula]

On Tue, 27 Aug 2024, Derek Foreman <derek.foreman@collabora.com> wrote:
> The largest infoframe we create is the DRM (Dynamic Range Mastering)
> infoframe which is 26 bytes + a 4 byte header, for a total of 30
> bytes.
>
> With HDMI_MAX_INFOFRAME_SIZE set to 29 bytes, as it is now, we
> allocate too little space to pack a DRM infoframe in
> write_device_infoframe(), leading to an ENOSPC return from
> hdmi_infoframe_pack(), and never calling the connector's
> write_infoframe() vfunc.
>
> Instead of having HDMI_MAX_INFOFRAME_SIZE defined in two places,
> replace HDMI_MAX_INFOFRAME_SIZE with HDMI_INFOFRAME_SIZE(MAX) and make
> MAX 27 bytes - which is defined by the HDMI specification to be the
> largest infoframe payload.
>
> Fixes: f378b77227bc ("drm/connector: hdmi: Add Infoframes generation")
> Fixes: c602e4959a0c ("drm/connector: hdmi: Create Infoframe DebugFS entries")
>

Superfluous blank line. Can be fixed while applying.

Reviewed-by: Jani Nikula <jani.nikula@intel.com>


> Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
> ---
>  drivers/gpu/drm/display/drm_hdmi_state_helper.c | 4 +---
>  drivers/gpu/drm/drm_debugfs.c                   | 4 +---
>  include/linux/hdmi.h                            | 9 +++++++++
>  3 files changed, 11 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> index 7854820089ec..feb7a3a75981 100644
> --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> @@ -521,8 +521,6 @@ int drm_atomic_helper_connector_hdmi_check(struct drm_connector *connector,
>  }
>  EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_check);
>  
> -#define HDMI_MAX_INFOFRAME_SIZE		29
> -
>  static int clear_device_infoframe(struct drm_connector *connector,
>  				  enum hdmi_infoframe_type type)
>  {
> @@ -563,7 +561,7 @@ static int write_device_infoframe(struct drm_connector *connector,
>  {
>  	const struct drm_connector_hdmi_funcs *funcs = connector->hdmi.funcs;
>  	struct drm_device *dev = connector->dev;
> -	u8 buffer[HDMI_MAX_INFOFRAME_SIZE];
> +	u8 buffer[HDMI_INFOFRAME_SIZE(MAX)];
>  	int ret;
>  	int len;
>  
> diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
> index 6b239a24f1df..9d3e6dd68810 100644
> --- a/drivers/gpu/drm/drm_debugfs.c
> +++ b/drivers/gpu/drm/drm_debugfs.c
> @@ -520,8 +520,6 @@ static const struct file_operations drm_connector_fops = {
>  	.write = connector_write
>  };
>  
> -#define HDMI_MAX_INFOFRAME_SIZE		29
> -
>  static ssize_t
>  audio_infoframe_read(struct file *filp, char __user *ubuf, size_t count, loff_t *ppos)
>  {
> @@ -579,7 +577,7 @@ static ssize_t _f##_read_infoframe(struct file *filp, \
>  	struct drm_connector *connector; \
>  	union hdmi_infoframe *frame; \
>  	struct drm_device *dev; \
> -	u8 buf[HDMI_MAX_INFOFRAME_SIZE]; \
> +	u8 buf[HDMI_INFOFRAME_SIZE(MAX)]; \
>  	ssize_t len = 0; \
>  	\
>  	connector = filp->private_data; \
> diff --git a/include/linux/hdmi.h b/include/linux/hdmi.h
> index 3bb87bf6bc65..455f855bc084 100644
> --- a/include/linux/hdmi.h
> +++ b/include/linux/hdmi.h
> @@ -59,6 +59,15 @@ enum hdmi_infoframe_type {
>  #define HDMI_DRM_INFOFRAME_SIZE    26
>  #define HDMI_VENDOR_INFOFRAME_SIZE  4
>  
> +/*
> + * HDMI 1.3a table 5-14 states that the largest InfoFrame_length is 27,
> + * not including the packet header or checksum byte. We include the
> + * checksum byte in HDMI_INFOFRAME_HEADER_SIZE, so this should allow
> + * HDMI_INFOFRAME_SIZE(MAX) to be the largest buffer we could ever need
> + * for any HDMI infoframe.
> + */
> +#define HDMI_MAX_INFOFRAME_SIZE    27
> +
>  #define HDMI_INFOFRAME_SIZE(type)	\
>  	(HDMI_INFOFRAME_HEADER_SIZE + HDMI_ ## type ## _INFOFRAME_SIZE)

-- 
Jani Nikula, Intel

Re: [PATCH v4] drm/connector: hdmi: Fix writing Dynamic Range Mastering infoframes

[Derek Foreman]

Gentle ping - is there anything more I need to do before this can land?

Thanks,
Derek

On 2024-08-28 03:31, Jani Nikula wrote:
> On Tue, 27 Aug 2024, Derek Foreman <derek.foreman@collabora.com> wrote:
>> The largest infoframe we create is the DRM (Dynamic Range Mastering)
>> infoframe which is 26 bytes + a 4 byte header, for a total of 30
>> bytes.
>>
>> With HDMI_MAX_INFOFRAME_SIZE set to 29 bytes, as it is now, we
>> allocate too little space to pack a DRM infoframe in
>> write_device_infoframe(), leading to an ENOSPC return from
>> hdmi_infoframe_pack(), and never calling the connector's
>> write_infoframe() vfunc.
>>
>> Instead of having HDMI_MAX_INFOFRAME_SIZE defined in two places,
>> replace HDMI_MAX_INFOFRAME_SIZE with HDMI_INFOFRAME_SIZE(MAX) and make
>> MAX 27 bytes - which is defined by the HDMI specification to be the
>> largest infoframe payload.
>>
>> Fixes: f378b77227bc ("drm/connector: hdmi: Add Infoframes generation")
>> Fixes: c602e4959a0c ("drm/connector: hdmi: Create Infoframe DebugFS entries")
>>
> Superfluous blank line. Can be fixed while applying.
>
> Reviewed-by: Jani Nikula <jani.nikula@intel.com>
>
>
>> Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
>> ---
>>   drivers/gpu/drm/display/drm_hdmi_state_helper.c | 4 +---
>>   drivers/gpu/drm/drm_debugfs.c                   | 4 +---
>>   include/linux/hdmi.h                            | 9 +++++++++
>>   3 files changed, 11 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
>> index 7854820089ec..feb7a3a75981 100644
>> --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c
>> +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
>> @@ -521,8 +521,6 @@ int drm_atomic_helper_connector_hdmi_check(struct drm_connector *connector,
>>   }
>>   EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_check);
>>   
>> -#define HDMI_MAX_INFOFRAME_SIZE		29
>> -
>>   static int clear_device_infoframe(struct drm_connector *connector,
>>   				  enum hdmi_infoframe_type type)
>>   {
>> @@ -563,7 +561,7 @@ static int write_device_infoframe(struct drm_connector *connector,
>>   {
>>   	const struct drm_connector_hdmi_funcs *funcs = connector->hdmi.funcs;
>>   	struct drm_device *dev = connector->dev;
>> -	u8 buffer[HDMI_MAX_INFOFRAME_SIZE];
>> +	u8 buffer[HDMI_INFOFRAME_SIZE(MAX)];
>>   	int ret;
>>   	int len;
>>   
>> diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
>> index 6b239a24f1df..9d3e6dd68810 100644
>> --- a/drivers/gpu/drm/drm_debugfs.c
>> +++ b/drivers/gpu/drm/drm_debugfs.c
>> @@ -520,8 +520,6 @@ static const struct file_operations drm_connector_fops = {
>>   	.write = connector_write
>>   };
>>   
>> -#define HDMI_MAX_INFOFRAME_SIZE		29
>> -
>>   static ssize_t
>>   audio_infoframe_read(struct file *filp, char __user *ubuf, size_t count, loff_t *ppos)
>>   {
>> @@ -579,7 +577,7 @@ static ssize_t _f##_read_infoframe(struct file *filp, \
>>   	struct drm_connector *connector; \
>>   	union hdmi_infoframe *frame; \
>>   	struct drm_device *dev; \
>> -	u8 buf[HDMI_MAX_INFOFRAME_SIZE]; \
>> +	u8 buf[HDMI_INFOFRAME_SIZE(MAX)]; \
>>   	ssize_t len = 0; \
>>   	\
>>   	connector = filp->private_data; \
>> diff --git a/include/linux/hdmi.h b/include/linux/hdmi.h
>> index 3bb87bf6bc65..455f855bc084 100644
>> --- a/include/linux/hdmi.h
>> +++ b/include/linux/hdmi.h
>> @@ -59,6 +59,15 @@ enum hdmi_infoframe_type {
>>   #define HDMI_DRM_INFOFRAME_SIZE    26
>>   #define HDMI_VENDOR_INFOFRAME_SIZE  4
>>   
>> +/*
>> + * HDMI 1.3a table 5-14 states that the largest InfoFrame_length is 27,
>> + * not including the packet header or checksum byte. We include the
>> + * checksum byte in HDMI_INFOFRAME_HEADER_SIZE, so this should allow
>> + * HDMI_INFOFRAME_SIZE(MAX) to be the largest buffer we could ever need
>> + * for any HDMI infoframe.
>> + */
>> +#define HDMI_MAX_INFOFRAME_SIZE    27
>> +
>>   #define HDMI_INFOFRAME_SIZE(type)	\
>>   	(HDMI_INFOFRAME_HEADER_SIZE + HDMI_ ## type ## _INFOFRAME_SIZE)

Re: [PATCH v4] drm/connector: hdmi: Fix writing Dynamic Range Mastering infoframes

[Jani Nikula]

On Mon, 16 Sep 2024, Derek Foreman <derek.foreman@collabora.com> wrote:
> Gentle ping - is there anything more I need to do before this can land?

I don't think so. FWIW, I bounced this to intel-gfx and got passing CI
results too.

Cc: drm-misc maintainers. Just wondering where to merge this. It's a fix
to commits in v6.11. Are you still planning on a drm-misc-next-fixes
pull request for v6.12-rc1? That would be the quickest way to get this
upstream.

BR,
Jani.


>
> Thanks,
> Derek
>
> On 2024-08-28 03:31, Jani Nikula wrote:
>> On Tue, 27 Aug 2024, Derek Foreman <derek.foreman@collabora.com> wrote:
>>> The largest infoframe we create is the DRM (Dynamic Range Mastering)
>>> infoframe which is 26 bytes + a 4 byte header, for a total of 30
>>> bytes.
>>>
>>> With HDMI_MAX_INFOFRAME_SIZE set to 29 bytes, as it is now, we
>>> allocate too little space to pack a DRM infoframe in
>>> write_device_infoframe(), leading to an ENOSPC return from
>>> hdmi_infoframe_pack(), and never calling the connector's
>>> write_infoframe() vfunc.
>>>
>>> Instead of having HDMI_MAX_INFOFRAME_SIZE defined in two places,
>>> replace HDMI_MAX_INFOFRAME_SIZE with HDMI_INFOFRAME_SIZE(MAX) and make
>>> MAX 27 bytes - which is defined by the HDMI specification to be the
>>> largest infoframe payload.
>>>
>>> Fixes: f378b77227bc ("drm/connector: hdmi: Add Infoframes generation")
>>> Fixes: c602e4959a0c ("drm/connector: hdmi: Create Infoframe DebugFS entries")
>>>
>> Superfluous blank line. Can be fixed while applying.
>>
>> Reviewed-by: Jani Nikula <jani.nikula@intel.com>
>>
>>
>>> Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
>>> ---
>>>   drivers/gpu/drm/display/drm_hdmi_state_helper.c | 4 +---
>>>   drivers/gpu/drm/drm_debugfs.c                   | 4 +---
>>>   include/linux/hdmi.h                            | 9 +++++++++
>>>   3 files changed, 11 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
>>> index 7854820089ec..feb7a3a75981 100644
>>> --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c
>>> +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
>>> @@ -521,8 +521,6 @@ int drm_atomic_helper_connector_hdmi_check(struct drm_connector *connector,
>>>   }
>>>   EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_check);
>>>   
>>> -#define HDMI_MAX_INFOFRAME_SIZE		29
>>> -
>>>   static int clear_device_infoframe(struct drm_connector *connector,
>>>   				  enum hdmi_infoframe_type type)
>>>   {
>>> @@ -563,7 +561,7 @@ static int write_device_infoframe(struct drm_connector *connector,
>>>   {
>>>   	const struct drm_connector_hdmi_funcs *funcs = connector->hdmi.funcs;
>>>   	struct drm_device *dev = connector->dev;
>>> -	u8 buffer[HDMI_MAX_INFOFRAME_SIZE];
>>> +	u8 buffer[HDMI_INFOFRAME_SIZE(MAX)];
>>>   	int ret;
>>>   	int len;
>>>   
>>> diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
>>> index 6b239a24f1df..9d3e6dd68810 100644
>>> --- a/drivers/gpu/drm/drm_debugfs.c
>>> +++ b/drivers/gpu/drm/drm_debugfs.c
>>> @@ -520,8 +520,6 @@ static const struct file_operations drm_connector_fops = {
>>>   	.write = connector_write
>>>   };
>>>   
>>> -#define HDMI_MAX_INFOFRAME_SIZE		29
>>> -
>>>   static ssize_t
>>>   audio_infoframe_read(struct file *filp, char __user *ubuf, size_t count, loff_t *ppos)
>>>   {
>>> @@ -579,7 +577,7 @@ static ssize_t _f##_read_infoframe(struct file *filp, \
>>>   	struct drm_connector *connector; \
>>>   	union hdmi_infoframe *frame; \
>>>   	struct drm_device *dev; \
>>> -	u8 buf[HDMI_MAX_INFOFRAME_SIZE]; \
>>> +	u8 buf[HDMI_INFOFRAME_SIZE(MAX)]; \
>>>   	ssize_t len = 0; \
>>>   	\
>>>   	connector = filp->private_data; \
>>> diff --git a/include/linux/hdmi.h b/include/linux/hdmi.h
>>> index 3bb87bf6bc65..455f855bc084 100644
>>> --- a/include/linux/hdmi.h
>>> +++ b/include/linux/hdmi.h
>>> @@ -59,6 +59,15 @@ enum hdmi_infoframe_type {
>>>   #define HDMI_DRM_INFOFRAME_SIZE    26
>>>   #define HDMI_VENDOR_INFOFRAME_SIZE  4
>>>   
>>> +/*
>>> + * HDMI 1.3a table 5-14 states that the largest InfoFrame_length is 27,
>>> + * not including the packet header or checksum byte. We include the
>>> + * checksum byte in HDMI_INFOFRAME_HEADER_SIZE, so this should allow
>>> + * HDMI_INFOFRAME_SIZE(MAX) to be the largest buffer we could ever need
>>> + * for any HDMI infoframe.
>>> + */
>>> +#define HDMI_MAX_INFOFRAME_SIZE    27
>>> +
>>>   #define HDMI_INFOFRAME_SIZE(type)	\
>>>   	(HDMI_INFOFRAME_HEADER_SIZE + HDMI_ ## type ## _INFOFRAME_SIZE)

-- 
Jani Nikula, Intel

Re: [PATCH v4] drm/connector: hdmi: Fix writing Dynamic Range Mastering infoframes

[Maxime Ripard]

On Tue, 27 Aug 2024 11:39:04 -0500, Derek Foreman wrote:
> The largest infoframe we create is the DRM (Dynamic Range Mastering)
> infoframe which is 26 bytes + a 4 byte header, for a total of 30
> bytes.
> 
> With HDMI_MAX_INFOFRAME_SIZE set to 29 bytes, as it is now, we
> allocate too little space to pack a DRM infoframe in
> write_device_infoframe(), leading to an ENOSPC return from
> hdmi_infoframe_pack(), and never calling the connector's
> write_infoframe() vfunc.
> 
> [...]

Applied to misc/kernel.git (drm-misc-fixes).

Thanks!
Maxime

Re: [PATCH v4] drm/connector: hdmi: Fix writing Dynamic Range Mastering infoframes

[Dmitry Baryshkov]

On Tue, Sep 24, 2024 at 04:13:08PM GMT, Maxime Ripard wrote:
> On Tue, 27 Aug 2024 11:39:04 -0500, Derek Foreman wrote:
> > The largest infoframe we create is the DRM (Dynamic Range Mastering)
> > infoframe which is 26 bytes + a 4 byte header, for a total of 30
> > bytes.
> > 
> > With HDMI_MAX_INFOFRAME_SIZE set to 29 bytes, as it is now, we
> > allocate too little space to pack a DRM infoframe in
> > write_device_infoframe(), leading to an ENOSPC return from
> > hdmi_infoframe_pack(), and never calling the connector's
> > write_infoframe() vfunc.
> > 
> > [...]
> 
> Applied to misc/kernel.git (drm-misc-fixes).

With an empty line between Fixes and the rest of the tags :-(

> 
> Thanks!
> Maxime
> 

-- 
With best wishes
Dmitry