Re: [PATCH 12/21] soundwire: amd: Check for NULL manager drvdata in sdw_amd_startup()

[Mukunda,Vijendar]

On 10/30/26 16:16, Lee Jones wrote:
> [You don't often get email from lee@xxxxxxxxxx. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
>
> If amd_sdw_manager_probe() fails or defers when registering a SoundWire
> manager platform device, dev_get_drvdata(&ctx->pdev[i]->dev) returns
> NULL.  sdw_amd_startup() passes this pointer directly to
> amd_sdw_manager_start(), which dereferences it unconditionally.
>
> Return -ENODEV in sdw_amd_startup() if dev_get_drvdata() returns NULL,
> matching sdw_amd_get_slave_info(), and clean up the allocated context
> and platform devices via sdw_amd_exit() if sdw_amd_startup() fails in
> sdw_amd_probe().

The sdw_amd_probe() cleanup fix — calling sdw_amd_exit() and
nulling *sdw_ctx on sdw_amd_startup() failure — is already
addressed in our v3 patch series posted for upstream review:

https://lore.kernel.org/alsa-devel/20261013085111.2009061-6-Vijendar.Mukunda@xxxxxxx/T/#u

The NULL check in sdw_amd_startup() is a valid observation and
will be addressed in our upcoming v4 patch series. Please hold
this patch until v4 is on-list to avoid conflicts.

> Fixes: ed5e8741b8db ("soundwire: amd: refactor amd soundwire manager device node creation")
> Closes: https://sashiko.dev/#/bug/linux-6834a8a0-632f-4c73-9174-0fe7e06b5303
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Lee Jones <lee@xxxxxxxxxx>
> ---
>   drivers/soundwire/amd_init.c | 13 ++++++++++++-
>   1 file changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/soundwire/amd_init.c b/drivers/soundwire/amd_init.c
> index 8e419ddfa516..adf410fafb7e 100644
> --- a/drivers/soundwire/amd_init.c
> +++ b/drivers/soundwire/amd_init.c
> @@ -156,6 +156,8 @@ static int sdw_amd_startup(struct sdw_amd_ctx *ctx)
>                  if (!(ctx->link_mask & BIT(i)))
>                          continue;
>                  amd_manager = dev_get_drvdata(&ctx->pdev[i]->dev);
> +               if (!amd_manager)
> +                       return -ENODEV;
>                  ret = amd_sdw_manager_start(amd_manager);
>                  if (ret)
>                          return ret;
> @@ -166,11 +168,20 @@ static int sdw_amd_startup(struct sdw_amd_ctx *ctx)
>
>   int sdw_amd_probe(struct sdw_amd_res *res, struct sdw_amd_ctx **sdw_ctx)
>   {
> +       int ret;
> +
>          *sdw_ctx = sdw_amd_probe_controller(res);
>          if (!*sdw_ctx)
>                  return -ENODEV;
>
> -       return sdw_amd_startup(*sdw_ctx);
> +       ret = sdw_amd_startup(*sdw_ctx);
> +       if (ret) {
> +               sdw_amd_exit(*sdw_ctx);
> +               *sdw_ctx = NULL;
> +               return ret;
> +       }
> +
> +       return 0;
>   }
>   EXPORT_SYMBOL_NS(sdw_amd_probe, "SOUNDWIRE_AMD_INIT");
>
> --
> 2.56.0.317.g454f8302e1-goog