Re: [PATCH linux-next v2 1/2] ASoC: rsnd: src: Avoid a potential deadlock

From: Jiada Wang
Date: Mon Mar 18 2019 - 23:35:23 EST


Hi Fabrizio

On 2019/03/14 3:19, Fabrizio Castro wrote:
Hello Jiada,

From: Jiada Wang <jiada_wang@xxxxxxxxxx>
Sent: 13 March 2019 11:56
Subject: Re: [PATCH linux-next v2 1/2] ASoC: rsnd: src: Avoid a potential deadlock

Hi Geert

On 2019/03/12 18:15, Geert Uytterhoeven wrote:
Hi Jiada, Fabrizio,

On Thu, Mar 7, 2019 at 7:17 AM Jiada Wang <jiada_wang@xxxxxxxxxx> wrote:
lockdep warns us that priv->lock and k->k_lock can cause a
deadlock when after acquire of k->k_lock, process is interrupted
by src, while in another routine of src .init, k->k_lock is
acquired with priv->lock held.

This patch avoids a potential deadlock by not calling soc_device_match()
in SRC .init callback, instead it adds new soc fields in priv->flags to
differentiate SoCs.

Fixes: linux-next commit 7674bec4fc09 ("ASoC: rsnd: update BSDSR/BSDISR handling")
Signed-off-by: Jiada Wang <jiada_wang@xxxxxxxxxx>
---
sound/soc/sh/rcar/core.c | 2 ++
sound/soc/sh/rcar/rsnd.h | 5 +++++
sound/soc/sh/rcar/src.c | 9 +--------
3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/sound/soc/sh/rcar/core.c b/sound/soc/sh/rcar/core.c
index 022996d2db13..4fe83e611c01 100644
--- a/sound/soc/sh/rcar/core.c
+++ b/sound/soc/sh/rcar/core.c
@@ -110,6 +110,8 @@ static const struct of_device_id rsnd_of_match[] = {
{ .compatible = "renesas,rcar_sound-gen1", .data = (void *)RSND_GEN1 },
{ .compatible = "renesas,rcar_sound-gen2", .data = (void *)RSND_GEN2 },
{ .compatible = "renesas,rcar_sound-gen3", .data = (void *)RSND_GEN3 },
+ /* Special Handling */
+ { .compatible = "renesas,rcar_sound-r8a77990", .data = (void *)(RSND_GEN3 | RSND_SOC_E) },

I guess we need an entry for RZ/G2E, too?

Geert has a point, I am looking at the User manual for the RZ/G2E and it looks like the
implementation for the RZ/G2E is the same as the one for the r8a77990


Sorry, I don't have user manual for RZ/G2E,
if you can let me know where to find RZ/G2E's user manual,
I can add entry for these SoCs

If you prefer I could add that after running some tests? I do have a board with a RZ/G2E.

Yes, please
since I have neither RZ/G2E board to test nor its user manual

Thanks,
Jiada
Thanks,
Fab


Thanks,
Jiada
Gr{oetje,eeting}s,

Geert