diff --git a/arch/arm/src/stm32f7/stm32_ethernet.c b/arch/arm/src/stm32f7/stm32_ethernet.c
index 92daf09f5d..28c80a43ef 100644
--- a/arch/arm/src/stm32f7/stm32_ethernet.c
+++ b/arch/arm/src/stm32f7/stm32_ethernet.c
@@ -1898,7 +1898,6 @@ static void stm32_receive(struct stm32_ethmac_s *priv)
 static void stm32_freeframe(struct stm32_ethmac_s *priv)
 {
   struct eth_txdesc_s *txdesc;
-  int i;
 
   ninfo("txhead: %p txtail: %p inflight: %d\n",
         priv->txhead, priv->txtail, priv->inflight);
@@ -1915,7 +1914,7 @@ static void stm32_freeframe(struct stm32_ethmac_s *priv)
       up_invalidate_dcache((uintptr_t)txdesc,
                            (uintptr_t)txdesc + sizeof(struct eth_txdesc_s));
 
-      for (i = 0; (txdesc->tdes0 & ETH_TDES0_OWN) == 0; i++)
+      while ((txdesc->tdes0 & ETH_TDES0_OWN) == 0)
         {
           /* There should be a buffer assigned to all in-flight
            * TX descriptors.
diff --git a/arch/arm/src/stm32h7/stm32_ethernet.c b/arch/arm/src/stm32h7/stm32_ethernet.c
index 3a0314578e..c2719303b4 100644
--- a/arch/arm/src/stm32h7/stm32_ethernet.c
+++ b/arch/arm/src/stm32h7/stm32_ethernet.c
@@ -2011,7 +2011,6 @@ static void stm32_freeframe(struct stm32_ethmac_s *priv)
 {
   struct eth_desc_s *txdesc;
   uint32_t des3_tmp;
-  int i;
 
   ninfo("txhead: %p txtail: %p inflight: %d\n",
         priv->txhead, priv->txtail, priv->inflight);
@@ -2028,7 +2027,7 @@ static void stm32_freeframe(struct stm32_ethmac_s *priv)
       up_invalidate_dcache((uintptr_t)txdesc,
                            (uintptr_t)txdesc + sizeof(struct eth_desc_s));
 
-      for (i = 0; (txdesc->des3 & ETH_TDES3_RD_OWN) == 0; i++)
+      while ((txdesc->des3 & ETH_TDES3_RD_OWN) == 0)
         {
           /* There should be a buffer assigned to all in-flight
            * TX descriptors.