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[PATCH v2 4/6] PCI: endpoint: pci-epf-ntb: Remove duplicate resource teardown

Koichiro Den posted 6 patches 1 month, 2 weeks ago
There is a newer version of this series
[PATCH v2 4/6] PCI: endpoint: pci-epf-ntb: Remove duplicate resource teardown
Posted by Koichiro Den 1 month, 2 weeks ago 
epf_ntb_epc_destroy() duplicates the teardown that the caller is
supposed to do later. This leads to an oops when .allow_link fails or
when .drop_link is performed. Remove the helper.

Also drop pci_epc_put(). EPC device refcounting is tied to configfs EPC
group lifetime, and pci_epc_put() in the .drop_link path is sufficient.

Cc: <stable@vger.kernel.org>
Fixes: 8b821cf76150 ("PCI: endpoint: Add EP function driver to provide NTB functionality")
Signed-off-by: Koichiro Den <den@valinux.co.jp>
---
 drivers/pci/endpoint/functions/pci-epf-ntb.c | 56 +-------------------
 1 file changed, 2 insertions(+), 54 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-ntb.c b/drivers/pci/endpoint/functions/pci-epf-ntb.c
index e01a98e74d21..7702ebb81d99 100644
--- a/drivers/pci/endpoint/functions/pci-epf-ntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-ntb.c
@@ -1494,47 +1494,6 @@ static int epf_ntb_db_mw_bar_init(struct epf_ntb *ntb,
 	return ret;
 }
 
-/**
- * epf_ntb_epc_destroy_interface() - Cleanup NTB EPC interface
- * @ntb: NTB device that facilitates communication between HOST1 and HOST2
- * @type: PRIMARY interface or SECONDARY interface
- *
- * Unbind NTB function device from EPC and relinquish reference to pci_epc
- * for each of the interface.
- */
-static void epf_ntb_epc_destroy_interface(struct epf_ntb *ntb,
-					  enum pci_epc_interface_type type)
-{
-	struct epf_ntb_epc *ntb_epc;
-	struct pci_epc *epc;
-	struct pci_epf *epf;
-
-	if (type < 0)
-		return;
-
-	epf = ntb->epf;
-	ntb_epc = ntb->epc[type];
-	if (!ntb_epc)
-		return;
-	epc = ntb_epc->epc;
-	pci_epc_remove_epf(epc, epf, type);
-	pci_epc_put(epc);
-}
-
-/**
- * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
- * @ntb: NTB device that facilitates communication between HOST1 and HOST2
- *
- * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB interfaces
- */
-static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
-{
-	enum pci_epc_interface_type type;
-
-	for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++)
-		epf_ntb_epc_destroy_interface(ntb, type);
-}
-
 /**
  * epf_ntb_epc_create_interface() - Create and initialize NTB EPC interface
  * @ntb: NTB device that facilitates communication between HOST1 and HOST2
@@ -1614,15 +1573,8 @@ static int epf_ntb_epc_create(struct epf_ntb *ntb)
 
 	ret = epf_ntb_epc_create_interface(ntb, epf->sec_epc,
 					   SECONDARY_INTERFACE);
-	if (ret) {
+	if (ret)
 		dev_err(dev, "SECONDARY intf: Fail to create NTB EPC\n");
-		goto err_epc_create;
-	}
-
-	return 0;
-
-err_epc_create:
-	epf_ntb_epc_destroy_interface(ntb, PRIMARY_INTERFACE);
 
 	return ret;
 }
@@ -1887,7 +1839,7 @@ static int epf_ntb_bind(struct pci_epf *epf)
 	ret = epf_ntb_init_epc_bar(ntb);
 	if (ret) {
 		dev_err(dev, "Failed to create NTB EPC\n");
-		goto err_bar_init;
+		return ret;
 	}
 
 	ret = epf_ntb_config_spad_bar_alloc_interface(ntb);
@@ -1909,9 +1861,6 @@ static int epf_ntb_bind(struct pci_epf *epf)
 err_bar_alloc:
 	epf_ntb_config_spad_bar_free(ntb);
 
-err_bar_init:
-	epf_ntb_epc_destroy(ntb);
-
 	return ret;
 }
 
@@ -1927,7 +1876,6 @@ static void epf_ntb_unbind(struct pci_epf *epf)
 
 	epf_ntb_epc_cleanup(ntb);
 	epf_ntb_config_spad_bar_free(ntb);
-	epf_ntb_epc_destroy(ntb);
 }
 
 #define EPF_NTB_R(_name)						\
-- 
2.48.1
Re: [PATCH v2 4/6] PCI: endpoint: pci-epf-ntb: Remove duplicate resource teardown
Posted by Frank Li 1 month, 2 weeks ago 
On Wed, Oct 29, 2025 at 05:03:19PM +0900, Koichiro Den wrote:
> epf_ntb_epc_destroy() duplicates the teardown that the caller is
> supposed to do later. This leads to an oops when .allow_link fails or
> when .drop_link is performed. Remove the helper.
>
> Also drop pci_epc_put(). EPC device refcounting is tied to configfs EPC
> group lifetime, and pci_epc_put() in the .drop_link path is sufficient.
>
> Cc: <stable@vger.kernel.org>
> Fixes: 8b821cf76150 ("PCI: endpoint: Add EP function driver to provide NTB functionality")
> Signed-off-by: Koichiro Den <den@valinux.co.jp>

Reviewed-by: Frank Li <Frank.Li@nxp.com>

> ---
>  drivers/pci/endpoint/functions/pci-epf-ntb.c | 56 +-------------------
>  1 file changed, 2 insertions(+), 54 deletions(-)
>
> diff --git a/drivers/pci/endpoint/functions/pci-epf-ntb.c b/drivers/pci/endpoint/functions/pci-epf-ntb.c
> index e01a98e74d21..7702ebb81d99 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-ntb.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-ntb.c
> @@ -1494,47 +1494,6 @@ static int epf_ntb_db_mw_bar_init(struct epf_ntb *ntb,
>  	return ret;
>  }
>
> -/**
> - * epf_ntb_epc_destroy_interface() - Cleanup NTB EPC interface
> - * @ntb: NTB device that facilitates communication between HOST1 and HOST2
> - * @type: PRIMARY interface or SECONDARY interface
> - *
> - * Unbind NTB function device from EPC and relinquish reference to pci_epc
> - * for each of the interface.
> - */
> -static void epf_ntb_epc_destroy_interface(struct epf_ntb *ntb,
> -					  enum pci_epc_interface_type type)
> -{
> -	struct epf_ntb_epc *ntb_epc;
> -	struct pci_epc *epc;
> -	struct pci_epf *epf;
> -
> -	if (type < 0)
> -		return;
> -
> -	epf = ntb->epf;
> -	ntb_epc = ntb->epc[type];
> -	if (!ntb_epc)
> -		return;
> -	epc = ntb_epc->epc;
> -	pci_epc_remove_epf(epc, epf, type);
> -	pci_epc_put(epc);
> -}
> -
> -/**
> - * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
> - * @ntb: NTB device that facilitates communication between HOST1 and HOST2
> - *
> - * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB interfaces
> - */
> -static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
> -{
> -	enum pci_epc_interface_type type;
> -
> -	for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++)
> -		epf_ntb_epc_destroy_interface(ntb, type);
> -}
> -
>  /**
>   * epf_ntb_epc_create_interface() - Create and initialize NTB EPC interface
>   * @ntb: NTB device that facilitates communication between HOST1 and HOST2
> @@ -1614,15 +1573,8 @@ static int epf_ntb_epc_create(struct epf_ntb *ntb)
>
>  	ret = epf_ntb_epc_create_interface(ntb, epf->sec_epc,
>  					   SECONDARY_INTERFACE);
> -	if (ret) {
> +	if (ret)
>  		dev_err(dev, "SECONDARY intf: Fail to create NTB EPC\n");
> -		goto err_epc_create;
> -	}
> -
> -	return 0;
> -
> -err_epc_create:
> -	epf_ntb_epc_destroy_interface(ntb, PRIMARY_INTERFACE);
>
>  	return ret;
>  }
> @@ -1887,7 +1839,7 @@ static int epf_ntb_bind(struct pci_epf *epf)
>  	ret = epf_ntb_init_epc_bar(ntb);
>  	if (ret) {
>  		dev_err(dev, "Failed to create NTB EPC\n");
> -		goto err_bar_init;
> +		return ret;
>  	}
>
>  	ret = epf_ntb_config_spad_bar_alloc_interface(ntb);
> @@ -1909,9 +1861,6 @@ static int epf_ntb_bind(struct pci_epf *epf)
>  err_bar_alloc:
>  	epf_ntb_config_spad_bar_free(ntb);
>
> -err_bar_init:
> -	epf_ntb_epc_destroy(ntb);
> -
>  	return ret;
>  }
>
> @@ -1927,7 +1876,6 @@ static void epf_ntb_unbind(struct pci_epf *epf)
>
>  	epf_ntb_epc_cleanup(ntb);
>  	epf_ntb_config_spad_bar_free(ntb);
> -	epf_ntb_epc_destroy(ntb);
>  }
>
>  #define EPF_NTB_R(_name)						\
> --
> 2.48.1
>

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