[PATCH] ALSA: pcm_drm_eld: rate-limit ELD parsing errors

[PATCH] ALSA: pcm_drm_eld: rate-limit ELD parsing errors

[Sav]

From: Sav <62543096+dongioia@users.noreply.github.com>

snd_parse_eld() is the generic helper used by ASoC hdmi-codec, equivalent
to the hdac_hdmi parse path Mark Brown rate-limited in
lkml.kernel.org/lkml/2025/6/13/1380. The same spam shows up here for the
same reason.

When a HDMI sink is not connected (for example a board with two HDMI
outputs and a cable in only one of them), userspace audio servers like
PipeWire keep opening the empty card. snd_parse_eld() then logs

    HDMI: Unknown ELD version 0

on every retry. On rk3588 that easily produces 30+ messages per burst.
A malformed ELD (MNL out of range) hits the same code path. Neither is
worth a separate dev_info() per occurrence; switch both to
dev_info_ratelimited().

Signed-off-by: Sav <62543096+dongioia@users.noreply.github.com>
---
 sound/core/pcm_drm_eld.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/core/pcm_drm_eld.c b/sound/core/pcm_drm_eld.c
index cb2eebaac85f..1941ee520063 100644
--- a/sound/core/pcm_drm_eld.c
+++ b/sound/core/pcm_drm_eld.c
@@ -334,7 +334,7 @@ int snd_parse_eld(struct device *dev, struct snd_parsed_hdmi_eld *e,
 	e->eld_ver = GRAB_BITS(buf, 0, 3, 5);
 	if (e->eld_ver != ELD_VER_CEA_861D &&
 	    e->eld_ver != ELD_VER_PARTIAL) {
-		dev_info(dev, "HDMI: Unknown ELD version %d\n", e->eld_ver);
+		dev_info_ratelimited(dev, "HDMI: Unknown ELD version %d\n", e->eld_ver);
 		goto out_fail;
 	}
 
@@ -357,7 +357,7 @@ int snd_parse_eld(struct device *dev, struct snd_parsed_hdmi_eld *e,
 	e->product_id	  = get_unaligned_le16(buf + 18);
 
 	if (mnl > ELD_MAX_MNL) {
-		dev_info(dev, "HDMI: MNL is reserved value %d\n", mnl);
+		dev_info_ratelimited(dev, "HDMI: MNL is reserved value %d\n", mnl);
 		goto out_fail;
 	} else if (ELD_FIXED_BYTES + mnl > size) {
 		dev_info(dev, "HDMI: out of range MNL %d\n", mnl);
-- 
2.54.0

Re: [PATCH] ALSA: pcm_drm_eld: rate-limit ELD parsing errors

[Takashi Iwai]

On Fri, 15 May 2026 17:58:36 +0200,
Sav wrote:
> 
> From: Sav <62543096+dongioia@users.noreply.github.com>
> 
> snd_parse_eld() is the generic helper used by ASoC hdmi-codec, equivalent
> to the hdac_hdmi parse path Mark Brown rate-limited in
> lkml.kernel.org/lkml/2025/6/13/1380. The same spam shows up here for the
> same reason.
> 
> When a HDMI sink is not connected (for example a board with two HDMI
> outputs and a cable in only one of them), userspace audio servers like
> PipeWire keep opening the empty card. snd_parse_eld() then logs
> 
>     HDMI: Unknown ELD version 0
> 
> on every retry. On rk3588 that easily produces 30+ messages per burst.
> A malformed ELD (MNL out of range) hits the same code path. Neither is
> worth a separate dev_info() per occurrence; switch both to
> dev_info_ratelimited().
> 
> Signed-off-by: Sav <62543096+dongioia@users.noreply.github.com>

Could you use the proper name (a real name or a known identity) and
the mail address for Signed-off-by and From, and resubmit?  It's a
legal requirement for the upstreaming.


thanks,

Takashi

> ---
>  sound/core/pcm_drm_eld.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/sound/core/pcm_drm_eld.c b/sound/core/pcm_drm_eld.c
> index cb2eebaac85f..1941ee520063 100644
> --- a/sound/core/pcm_drm_eld.c
> +++ b/sound/core/pcm_drm_eld.c
> @@ -334,7 +334,7 @@ int snd_parse_eld(struct device *dev, struct snd_parsed_hdmi_eld *e,
>  	e->eld_ver = GRAB_BITS(buf, 0, 3, 5);
>  	if (e->eld_ver != ELD_VER_CEA_861D &&
>  	    e->eld_ver != ELD_VER_PARTIAL) {
> -		dev_info(dev, "HDMI: Unknown ELD version %d\n", e->eld_ver);
> +		dev_info_ratelimited(dev, "HDMI: Unknown ELD version %d\n", e->eld_ver);
>  		goto out_fail;
>  	}
>  
> @@ -357,7 +357,7 @@ int snd_parse_eld(struct device *dev, struct snd_parsed_hdmi_eld *e,
>  	e->product_id	  = get_unaligned_le16(buf + 18);
>  
>  	if (mnl > ELD_MAX_MNL) {
> -		dev_info(dev, "HDMI: MNL is reserved value %d\n", mnl);
> +		dev_info_ratelimited(dev, "HDMI: MNL is reserved value %d\n", mnl);
>  		goto out_fail;
>  	} else if (ELD_FIXED_BYTES + mnl > size) {
>  		dev_info(dev, "HDMI: out of range MNL %d\n", mnl);
> -- 
> 2.54.0
> 

[PATCH RESEND] ALSA: pcm_drm_eld: rate-limit ELD parsing errors

[Francesco Saverio Pavone]

Mirror of Mark Brown's ASoC: hdac_hdmi rate-limit patch (commit
[lkml.kernel.org/lkml/2025/6/13/1380]) for the generic snd_parse_eld()
helper used by ASoC hdmi-codec.

When a HDMI sink is disconnected (e.g. a board with two HDMI outputs and
only one cable), userspace audio servers like PipeWire keep probing the
disconnected card and trigger:

    HDMI: Unknown ELD version 0

at every probe — easily 30+ messages per burst on rk3588. The same
applies to malformed ELD (MNL out of range). Both conditions are
expected when no sink is attached; rate-limit the dev_info() so the
kernel ring buffer does not fill up.

Signed-off-by: Francesco Saverio Pavone <pavone.lawyer@gmail.com>
---
 sound/core/pcm_drm_eld.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/core/pcm_drm_eld.c b/sound/core/pcm_drm_eld.c
index cb2eebaac85f..1941ee520063 100644
--- a/sound/core/pcm_drm_eld.c
+++ b/sound/core/pcm_drm_eld.c
@@ -334,7 +334,7 @@ int snd_parse_eld(struct device *dev, struct snd_parsed_hdmi_eld *e,
 	e->eld_ver = GRAB_BITS(buf, 0, 3, 5);
 	if (e->eld_ver != ELD_VER_CEA_861D &&
 	    e->eld_ver != ELD_VER_PARTIAL) {
-		dev_info(dev, "HDMI: Unknown ELD version %d\n", e->eld_ver);
+		dev_info_ratelimited(dev, "HDMI: Unknown ELD version %d\n", e->eld_ver);
 		goto out_fail;
 	}
 
@@ -357,7 +357,7 @@ int snd_parse_eld(struct device *dev, struct snd_parsed_hdmi_eld *e,
 	e->product_id	  = get_unaligned_le16(buf + 18);
 
 	if (mnl > ELD_MAX_MNL) {
-		dev_info(dev, "HDMI: MNL is reserved value %d\n", mnl);
+		dev_info_ratelimited(dev, "HDMI: MNL is reserved value %d\n", mnl);
 		goto out_fail;
 	} else if (ELD_FIXED_BYTES + mnl > size) {
 		dev_info(dev, "HDMI: out of range MNL %d\n", mnl);
-- 
2.54.0

Re: [PATCH RESEND] ALSA: pcm_drm_eld: rate-limit ELD parsing errors

[Takashi Iwai]

On Sat, 16 May 2026 16:12:44 +0200,
Francesco Saverio Pavone wrote:
> 
> 
> Mirror of Mark Brown's ASoC: hdac_hdmi rate-limit patch (commit
> [lkml.kernel.org/lkml/2025/6/13/1380]) for the generic snd_parse_eld()
> helper used by ASoC hdmi-codec.
> 
> When a HDMI sink is disconnected (e.g. a board with two HDMI outputs and
> only one cable), userspace audio servers like PipeWire keep probing the
> disconnected card and trigger:
> 
>     HDMI: Unknown ELD version 0
> 
> at every probe ― easily 30+ messages per burst on rk3588. The same
> applies to malformed ELD (MNL out of range). Both conditions are
> expected when no sink is attached; rate-limit the dev_info() so the
> kernel ring buffer does not fill up.
> 
> Signed-off-by: Francesco Saverio Pavone <pavone.lawyer@gmail.com>

Applied now.  Thanks.


Takashi