diff options
| author | Dragos Tatulea <dtatulea@nvidia.com> | 2024-11-07 21:35:24 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-11-12 06:23:38 +0300 |
| commit | dd6e972cc5890d91d6749bb48e3912721c4e4b25 (patch) | |
| tree | df20a8014aca08b42c3fc2f4618b476213294f4f | |
| parent | 9ca314419930f9135727e39d77e66262d5f7bef6 (diff) | |
| download | linux-dd6e972cc5890d91d6749bb48e3912721c4e4b25.tar.xz | |
net/mlx5e: kTLS, Fix incorrect page refcounting
The kTLS tx handling code is using a mix of get_page() and
page_ref_inc() APIs to increment the page reference. But on the release
path (mlx5e_ktls_tx_handle_resync_dump_comp()), only put_page() is used.
This is an issue when using pages from large folios: the get_page()
references are stored on the folio page while the page_ref_inc()
references are stored directly in the given page. On release the folio
page will be dereferenced too many times.
This was found while doing kTLS testing with sendfile() + ZC when the
served file was read from NFS on a kernel with NFS large folios support
(commit 49b29a573da8 ("nfs: add support for large folios")).
Fixes: 84d1bb2b139e ("net/mlx5e: kTLS, Limit DUMP wqe size")
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20241107183527.676877-5-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c index d61be26a4df1..3db31cc10719 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c @@ -660,7 +660,7 @@ tx_sync_info_get(struct mlx5e_ktls_offload_context_tx *priv_tx, while (remaining > 0) { skb_frag_t *frag = &record->frags[i]; - get_page(skb_frag_page(frag)); + page_ref_inc(skb_frag_page(frag)); remaining -= skb_frag_size(frag); info->frags[i++] = *frag; } @@ -763,7 +763,7 @@ void mlx5e_ktls_tx_handle_resync_dump_comp(struct mlx5e_txqsq *sq, stats = sq->stats; mlx5e_tx_dma_unmap(sq->pdev, dma); - put_page(wi->resync_dump_frag_page); + page_ref_dec(wi->resync_dump_frag_page); stats->tls_dump_packets++; stats->tls_dump_bytes += wi->num_bytes; } @@ -816,12 +816,12 @@ mlx5e_ktls_tx_handle_ooo(struct mlx5e_ktls_offload_context_tx *priv_tx, err_out: for (; i < info.nr_frags; i++) - /* The put_page() here undoes the page ref obtained in tx_sync_info_get(). + /* The page_ref_dec() here undoes the page ref obtained in tx_sync_info_get(). * Page refs obtained for the DUMP WQEs above (by page_ref_add) will be * released only upon their completions (or in mlx5e_free_txqsq_descs, * if channel closes). */ - put_page(skb_frag_page(&info.frags[i])); + page_ref_dec(skb_frag_page(&info.frags[i])); return MLX5E_KTLS_SYNC_FAIL; } |