diff mbox series

[net-next,10/13] net/mlx5e: allocate 'indirection_rqt' buffer dynamically

Message ID 20210312233851.494832-11-saeed@kernel.org (mailing list archive)
State Accepted
Delegated to: Netdev Maintainers
Headers show
Series [net-next,01/13] net/mlx5: DR, Fixed typo in STE v0 | expand

Checks

Context Check Description
netdev/cover_letter success Pull request
netdev/fixes_present success Link
netdev/patch_count success Link
netdev/tree_selection success Clearly marked for net-next
netdev/subject_prefix success Link
netdev/cc_maintainers warning 5 maintainers not CCed: leon@kernel.org clang-built-linux@googlegroups.com nathan@kernel.org ndesaulniers@google.com linux-rdma@vger.kernel.org
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 43 lines checked
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/header_inline success Link

Commit Message

Saeed Mahameed March 12, 2021, 11:38 p.m. UTC 
From: Arnd Bergmann <arnd@arndb.de>

Increasing the size of the indirection_rqt array from 128 to 256 bytes
pushed the stack usage of the mlx5e_hairpin_fill_rqt_rqns() function
over the warning limit when building with clang and CONFIG_KASAN:

drivers/net/ethernet/mellanox/mlx5/core/en_tc.c:970:1: error: stack frame size of 1180 bytes in function 'mlx5e_tc_add_nic_flow' [-Werror,-Wframe-larger-than=]

Using dynamic allocation here is safe because the caller does the
same, and it reduces the stack usage of the function to just a few
bytes.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_tc.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
index dc126389291d..c72725c3f53b 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
@@ -445,12 +445,16 @@  static void mlx5e_hairpin_destroy_transport(struct mlx5e_hairpin *hp)
 	mlx5_core_dealloc_transport_domain(hp->func_mdev, hp->tdn);
 }
 
-static void mlx5e_hairpin_fill_rqt_rqns(struct mlx5e_hairpin *hp, void *rqtc)
+static int mlx5e_hairpin_fill_rqt_rqns(struct mlx5e_hairpin *hp, void *rqtc)
 {
-	u32 indirection_rqt[MLX5E_INDIR_RQT_SIZE], rqn;
+	u32 *indirection_rqt, rqn;
 	struct mlx5e_priv *priv = hp->func_priv;
 	int i, ix, sz = MLX5E_INDIR_RQT_SIZE;
 
+	indirection_rqt = kzalloc(sz, GFP_KERNEL);
+	if (!indirection_rqt)
+		return -ENOMEM;
+
 	mlx5e_build_default_indir_rqt(indirection_rqt, sz,
 				      hp->num_channels);
 
@@ -462,6 +466,9 @@  static void mlx5e_hairpin_fill_rqt_rqns(struct mlx5e_hairpin *hp, void *rqtc)
 		rqn = hp->pair->rqn[ix];
 		MLX5_SET(rqtc, rqtc, rq_num[i], rqn);
 	}
+
+	kfree(indirection_rqt);
+	return 0;
 }
 
 static int mlx5e_hairpin_create_indirect_rqt(struct mlx5e_hairpin *hp)
@@ -482,12 +489,15 @@  static int mlx5e_hairpin_create_indirect_rqt(struct mlx5e_hairpin *hp)
 	MLX5_SET(rqtc, rqtc, rqt_actual_size, sz);
 	MLX5_SET(rqtc, rqtc, rqt_max_size, sz);
 
-	mlx5e_hairpin_fill_rqt_rqns(hp, rqtc);
+	err = mlx5e_hairpin_fill_rqt_rqns(hp, rqtc);
+	if (err)
+		goto out;
 
 	err = mlx5_core_create_rqt(mdev, in, inlen, &hp->indir_rqt.rqtn);
 	if (!err)
 		hp->indir_rqt.enabled = true;
 
+out:
 	kvfree(in);
 	return err;
 }