[dpdk-stable] [PATCH 19.11] net/mlx5: fix incorrect r/w lock usage in DMA unmap

[Feifei Wang]

[ upstream commit 1c196da274b82e6f1642bde7b1c407a2066caee1 ]

For mlx5 DMA unmap, write lock should be used for rebuilding memory
region cache table rather than read lock.

Fixes: 989e999d9305 ("net/mlx5: support PCI device DMA map and unmap")
Cc: shahafs at mellanox.com
Cc: stable at dpdk.org

Signed-off-by: Feifei Wang <feifei.wang2 at arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang at arm.com>
---
 drivers/net/mlx5/mlx5_mr.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_mr.c b/drivers/net/mlx5/mlx5_mr.c
index 54a11bd5d1..71c2254c91 100644
--- a/drivers/net/mlx5/mlx5_mr.c
+++ b/drivers/net/mlx5/mlx5_mr.c
@@ -1397,10 +1397,10 @@ mlx5_dma_unmap(struct rte_pci_device *pdev, void *addr,
 	}
 	priv = dev->data->dev_private;
 	sh = priv->sh;
-	rte_rwlock_read_lock(&sh->mr.rwlock);
+	rte_rwlock_write_lock(&sh->mr.rwlock);
 	mr = mr_lookup_dev_list(sh, &entry, (uintptr_t)addr);
 	if (!mr) {
-		rte_rwlock_read_unlock(&sh->mr.rwlock);
+		rte_rwlock_write_unlock(&sh->mr.rwlock);
 		DRV_LOG(WARNING, "address 0x%" PRIxPTR " wasn't registered "
 				 "to PCI device %p", (uintptr_t)addr,
 				 (void *)pdev);
@@ -1424,7 +1424,7 @@ mlx5_dma_unmap(struct rte_pci_device *pdev, void *addr,
 	++sh->mr.dev_gen;
 	DEBUG("broadcasting local cache flush, gen=%d",	sh->mr.dev_gen);
 	rte_smp_wmb();
-	rte_rwlock_read_unlock(&sh->mr.rwlock);
+	rte_rwlock_write_unlock(&sh->mr.rwlock);
 	return 0;
 }
 
-- 
2.25.1