Re: [PATCH] cxl: Fix devm device for cxl_fwctl initialization

[Dave Jiang <dave.jiang@intel.com>]

On 4/17/25 5:29 PM, Dave Jiang wrote:
> Testing revealed error message of for a CXL memdev that has Feature support:
> [   56.690430] cxl mem0: Resources present before probing
> 
> Attach the allocation of cxl_fwctl to the parent device of cxl_memdev.
> devm_add_* calls for cxl_memdev should not happen before the memdev
> probe function or outside the scope of the memdev driver.
> 
> Fixes: 858ce2f56b52 ("cxl: Add FWCTL support to CXL")
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Applied to cxl/fixes

> ---
>  drivers/cxl/core/features.c  | 4 ++--
>  drivers/cxl/pci.c            | 2 +-
>  include/cxl/features.h       | 5 +++--
>  tools/testing/cxl/test/mem.c | 2 +-
>  4 files changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/cxl/core/features.c b/drivers/cxl/core/features.c
> index f4daefe3180e..150a1776480a 100644
> --- a/drivers/cxl/core/features.c
> +++ b/drivers/cxl/core/features.c
> @@ -677,7 +677,7 @@ static void free_memdev_fwctl(void *_fwctl_dev)
>  	fwctl_put(fwctl_dev);
>  }
>  
> -int devm_cxl_setup_fwctl(struct cxl_memdev *cxlmd)
> +int devm_cxl_setup_fwctl(struct device *host, struct cxl_memdev *cxlmd)
>  {
>  	struct cxl_dev_state *cxlds = cxlmd->cxlds;
>  	struct cxl_features_state *cxlfs;
> @@ -700,7 +700,7 @@ int devm_cxl_setup_fwctl(struct cxl_memdev *cxlmd)
>  	if (rc)
>  		return rc;
>  
> -	return devm_add_action_or_reset(&cxlmd->dev, free_memdev_fwctl,
> +	return devm_add_action_or_reset(host, free_memdev_fwctl,
>  					no_free_ptr(fwctl_dev));
>  }
>  EXPORT_SYMBOL_NS_GPL(devm_cxl_setup_fwctl, "CXL");
> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> index 7b14a154463c..785aa2af5eaa 100644
> --- a/drivers/cxl/pci.c
> +++ b/drivers/cxl/pci.c
> @@ -1018,7 +1018,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>  	if (rc)
>  		return rc;
>  
> -	rc = devm_cxl_setup_fwctl(cxlmd);
> +	rc = devm_cxl_setup_fwctl(&pdev->dev, cxlmd);
>  	if (rc)
>  		dev_dbg(&pdev->dev, "No CXL FWCTL setup\n");
>  
> diff --git a/include/cxl/features.h b/include/cxl/features.h
> index a3bb34694c06..5f7f842765a5 100644
> --- a/include/cxl/features.h
> +++ b/include/cxl/features.h
> @@ -66,7 +66,7 @@ struct cxl_memdev;
>  #ifdef CONFIG_CXL_FEATURES
>  inline struct cxl_features_state *to_cxlfs(struct cxl_dev_state *cxlds);
>  int devm_cxl_setup_features(struct cxl_dev_state *cxlds);
> -int devm_cxl_setup_fwctl(struct cxl_memdev *cxlmd);
> +int devm_cxl_setup_fwctl(struct device *host, struct cxl_memdev *cxlmd);
>  #else
>  static inline struct cxl_features_state *to_cxlfs(struct cxl_dev_state *cxlds)
>  {
> @@ -78,7 +78,8 @@ static inline int devm_cxl_setup_features(struct cxl_dev_state *cxlds)
>  	return -EOPNOTSUPP;
>  }
>  
> -static inline int devm_cxl_setup_fwctl(struct cxl_memdev *cxlmd)
> +static inline int devm_cxl_setup_fwctl(struct device *host,
> +				       struct cxl_memdev *cxlmd)
>  {
>  	return -EOPNOTSUPP;
>  }
> diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
> index f2957a3e36fe..bf9caa908f89 100644
> --- a/tools/testing/cxl/test/mem.c
> +++ b/tools/testing/cxl/test/mem.c
> @@ -1780,7 +1780,7 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
>  	if (rc)
>  		return rc;
>  
> -	rc = devm_cxl_setup_fwctl(cxlmd);
> +	rc = devm_cxl_setup_fwctl(&pdev->dev, cxlmd);
>  	if (rc)
>  		dev_dbg(dev, "No CXL FWCTL setup\n");
>