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

[Feifei Wang]

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: shah...@mellanox.com
Cc: sta...@dpdk.org

Signed-off-by: Feifei Wang <feifei.wa...@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.w...@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 e791b6338d..45a122f4f9 100644
--- a/drivers/net/mlx5/mlx5_mr.c
+++ b/drivers/net/mlx5/mlx5_mr.c
@@ -395,10 +395,10 @@ mlx5_dma_unmap(struct rte_pci_device *pdev, void *addr,
        }
        priv = dev->data->dev_private;
        sh = priv->sh;
-       rte_rwlock_read_lock(&sh->share_cache.rwlock);
+       rte_rwlock_write_lock(&sh->share_cache.rwlock);
        mr = mlx5_mr_lookup_list(&sh->share_cache, &entry, (uintptr_t)addr);
        if (!mr) {
-               rte_rwlock_read_unlock(&sh->share_cache.rwlock);
+               rte_rwlock_write_unlock(&sh->share_cache.rwlock);
                DRV_LOG(WARNING, "address 0x%" PRIxPTR " wasn't registered "
                                 "to PCI device %p", (uintptr_t)addr,
                                 (void *)pdev);
@@ -423,7 +423,7 @@ mlx5_dma_unmap(struct rte_pci_device *pdev, void *addr,
        DRV_LOG(DEBUG, "broadcasting local cache flush, gen=%d",
              sh->share_cache.dev_gen);
        rte_smp_wmb();
-       rte_rwlock_read_unlock(&sh->share_cache.rwlock);
+       rte_rwlock_write_unlock(&sh->share_cache.rwlock);
        return 0;
 }
 
-- 
2.25.1