[PATCH] staging: octeon: fix FPA output buffer pool leak on teardown

[Oscar Alejandro Sánchez Lucero via B4 Relay]

From: Oscar Alejandro Sánchez Lucero <aleszlucero@xxxxxxxxx>

cvm_oct_configure_common_hw() allocates 1024 buffers for
CVMX_FPA_OUTPUT_BUFFER_POOL, but both the probe error path and
cvm_oct_remove() only free 128 buffers when calling
cvm_oct_mem_empty_fpa(), leaking 896 buffers on driver teardown.

Define OCTEON_NUM_OUTPUT_BUFFERS as 1024 and use it consistently when
filling and emptying CVMX_FPA_OUTPUT_BUFFER_POOL.

Signed-off-by: Oscar Alejandro Sánchez Lucero <aleszlucero@xxxxxxxxx>
---
This patch resolves a resource management bug causing physical hardware buffer 
leaks upon driver failure rollbacks and module extraction.

1. Introduce OCTEON_NUM_OUTPUT_BUFFERS to consistently fill and empty 1024 
   buffers within CVMX_FPA_OUTPUT_BUFFER_POOL, avoiding an 896 buffer leak.

Oscar Alejandro Sánchez Lucero (1):
  staging: octeon: fix FPA output buffer pool leak on teardown
---
 drivers/staging/octeon/ethernet.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/octeon/ethernet.c b/drivers/staging/octeon/ethernet.c
index 42ec4b8324a8..a74d122d9bb1 100644
--- a/drivers/staging/octeon/ethernet.c
+++ b/drivers/staging/octeon/ethernet.c
@@ -29,6 +29,7 @@
 #include "ethernet-util.h"
 
 #define OCTEON_MAX_MTU 65392
+#define OCTEON_NUM_OUTPUT_BUFFERS 1024
 
 static int num_packet_buffers = 1024;
 module_param(num_packet_buffers, int, 0444);
@@ -162,7 +163,8 @@ static void cvm_oct_configure_common_hw(struct platform_device *pdev)
 			     num_packet_buffers);
 	if (CVMX_FPA_OUTPUT_BUFFER_POOL != CVMX_FPA_PACKET_POOL)
 		cvm_oct_mem_fill_fpa(pdev, CVMX_FPA_OUTPUT_BUFFER_POOL,
-				     CVMX_FPA_OUTPUT_BUFFER_POOL_SIZE, 1024);
+				     CVMX_FPA_OUTPUT_BUFFER_POOL_SIZE,
+				     OCTEON_NUM_OUTPUT_BUFFERS);
 
 #ifdef __LITTLE_ENDIAN
 	{
@@ -974,7 +976,8 @@ static int cvm_oct_probe(struct platform_device *pdev)
 			      num_packet_buffers);
 	if (CVMX_FPA_OUTPUT_BUFFER_POOL != CVMX_FPA_PACKET_POOL)
 		cvm_oct_mem_empty_fpa(pdev, CVMX_FPA_OUTPUT_BUFFER_POOL,
-				      CVMX_FPA_OUTPUT_BUFFER_POOL_SIZE, 128);
+				      CVMX_FPA_OUTPUT_BUFFER_POOL_SIZE,
+				      OCTEON_NUM_OUTPUT_BUFFERS);
 
 	return ret;
 }
@@ -1009,7 +1012,8 @@ static void cvm_oct_remove(struct platform_device *pdev)
 			      num_packet_buffers);
 	if (CVMX_FPA_OUTPUT_BUFFER_POOL != CVMX_FPA_PACKET_POOL)
 		cvm_oct_mem_empty_fpa(pdev, CVMX_FPA_OUTPUT_BUFFER_POOL,
-				      CVMX_FPA_OUTPUT_BUFFER_POOL_SIZE, 128);
+				      CVMX_FPA_OUTPUT_BUFFER_POOL_SIZE,
+				      OCTEON_NUM_OUTPUT_BUFFERS);
 }
 
 static const struct of_device_id cvm_oct_match[] = {

---
base-commit: ddfe51b0a0f5dc9e415cc2c8ad8db17532dd426b
change-id: 20261108-octeon-fpa-leak-fix-v1-a1d31e978c82

Best regards,
-- 
Oscar Alejandro Sánchez Lucero <aleszlucero@xxxxxxxxx>