diff mbox series

[net-next,2/2] net/dpaa2: Avoid explicit cpumask var allocation on stack

Message ID 20240329105610.922675-3-dawei.li@shingroup.cn (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series Avoid explicit cpumask var allocation on stack | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 943 this patch: 943
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 954 this patch: 954
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 954 this patch: 954
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 36 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-03-31--03-00 (tests: 953)

Commit Message

Dawei Li March 29, 2024, 10:56 a.m. UTC
For CONFIG_CPUMASK_OFFSTACK=y kernel, explicit allocation of cpumask
variable on stack is not recommended since it can cause potential stack
overflow.

Instead, kernel code should always use *cpumask_var API(s) to allocate
cpumask var in config-neutral way, leaving allocation strategy to
CONFIG_CPUMASK_OFFSTACK.

Use *cpumask_var API(s) to address it.

Signed-off-by: Dawei Li <dawei.li@shingroup.cn>
---
 drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
index 888509cf1f21..40e881829595 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
@@ -2896,11 +2896,14 @@  static int dpaa2_eth_xdp_xmit(struct net_device *net_dev, int n,
 static int update_xps(struct dpaa2_eth_priv *priv)
 {
 	struct net_device *net_dev = priv->net_dev;
-	struct cpumask xps_mask;
-	struct dpaa2_eth_fq *fq;
 	int i, num_queues, netdev_queues;
+	struct dpaa2_eth_fq *fq;
+	cpumask_var_t xps_mask;
 	int err = 0;
 
+	if (!alloc_cpumask_var(&xps_mask, GFP_KERNEL))
+		return -ENOMEM;
+
 	num_queues = dpaa2_eth_queue_count(priv);
 	netdev_queues = (net_dev->num_tc ? : 1) * num_queues;
 
@@ -2910,16 +2913,17 @@  static int update_xps(struct dpaa2_eth_priv *priv)
 	for (i = 0; i < netdev_queues; i++) {
 		fq = &priv->fq[i % num_queues];
 
-		cpumask_clear(&xps_mask);
-		cpumask_set_cpu(fq->target_cpu, &xps_mask);
+		cpumask_clear(xps_mask);
+		cpumask_set_cpu(fq->target_cpu, xps_mask);
 
-		err = netif_set_xps_queue(net_dev, &xps_mask, i);
+		err = netif_set_xps_queue(net_dev, xps_mask, i);
 		if (err) {
 			netdev_warn_once(net_dev, "Error setting XPS queue\n");
 			break;
 		}
 	}
 
+	free_cpumask_var(xps_mask);
 	return err;
 }