[PATCH 0/3] Ice Tx Scheduler Fixes

[PATCH 0/3] Ice Tx Scheduler Fixes

[Ciara Loftus]

Three fixes for the ice Tx Scheduler: reenable strict priority, fix debug printing and prevent a
potential null dereference.

Ciara Loftus (3):
  net/ice: check for null before dereferencing
  net/ice: fix priority mode printing in Tx scheduler dump
  net/ice: re-enable strict priority on non-root levels

 drivers/net/intel/ice/ice_diagnose.c |  2 +-
 drivers/net/intel/ice/ice_tm.c       | 10 ++++++++--
 2 files changed, 9 insertions(+), 3 deletions(-)

-- 
2.43.0

[PATCH 1/3] net/ice: check for null before dereferencing

[Ciara Loftus]

When commiting a new Tx scheduler hierarchy we assume the user has
created a root node. However if they have not, it leads to an invalid
memory access. While this would be an invalid configuration by the user
we should still prevent the invalid memory access from happening. Do so
by ensuring the root node is non null before dereferencing.

Fixes: 715d449a965b ("net/ice: enhance Tx scheduler hierarchy support")
Cc: stable@dpdk.org

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
---
 drivers/net/intel/ice/ice_tm.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/intel/ice/ice_tm.c b/drivers/net/intel/ice/ice_tm.c
index f2d8e12181..db895613cc 100644
--- a/drivers/net/intel/ice/ice_tm.c
+++ b/drivers/net/intel/ice/ice_tm.c
@@ -816,8 +816,13 @@ commit_new_hierarchy(struct rte_eth_dev *dev)
 	uint16_t nodes_created_per_level[ICE_TM_MAX_LAYERS] = {0};
 	uint8_t q_lvl = ice_get_leaf_level(pf);
 	uint8_t qg_lvl = q_lvl - 1;
-
 	struct ice_sched_node *new_vsi_root = hw->vsi_ctx[pf->main_vsi->idx]->sched.vsi_node[0];
+
+	if (sw_root == NULL) {
+		PMD_DRV_LOG(ERR, "No root node defined in TM hierarchy");
+		return -1;
+	}
+
 	/* handle case where VSI node needs to move DOWN the hierarchy */
 	while (new_vsi_root->tx_sched_layer < new_root_level) {
 		if (new_vsi_root->num_children == 0)
-- 
2.43.0

[PATCH 2/3] net/ice: fix priority mode printing in Tx scheduler dump

[Ciara Loftus]

A value of zero in bit 4 of the generic data means that strict priority
is enabled. Prior to this commit it was being interpreted as WFQ being
enabled. Fix this.

Fixes: ab4eaf9a8a31 ("net/ice: dump Tx scheduling tree")
Cc: stable@dpdk.org

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
---
 drivers/net/intel/ice/ice_diagnose.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/intel/ice/ice_diagnose.c b/drivers/net/intel/ice/ice_diagnose.c
index 298d1eda5c..a58279a116 100644
--- a/drivers/net/intel/ice/ice_diagnose.c
+++ b/drivers/net/intel/ice/ice_diagnose.c
@@ -641,7 +641,7 @@ void print_node(const struct rte_eth_dev_data *ethdata,
 	fprintf(stream, "\t\t\t\t<tr>\n");
 	fprintf(stream, "\t\t\t\t\t<td> priority mode</td>\n");
 	fprintf(stream, "\t\t\t\t\t<td>");
-	print_priority_mode(stream, ((data->data.generic >> 4) & 0x1) != 0);
+	print_priority_mode(stream, ((data->data.generic >> 4) & 0x1) == 0);
 	fprintf(stream,	"</td>\n");
 	fprintf(stream, "\t\t\t\t</tr>\n");
 
-- 
2.43.0

[PATCH 3/3] net/ice: re-enable strict priority on non-root levels

[Ciara Loftus]

Commit 715d449a965b ("net/ice: enhance Tx scheduler hierarchy support")
disabled strict priority on all levels however it will work on all
levels except for the root level. This commit re-enables configurability
of priority on non-root levels.

Fixes: 715d449a965b ("net/ice: enhance Tx scheduler hierarchy support")
Cc: stable@dpdk.org

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
---
 drivers/net/intel/ice/ice_tm.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/intel/ice/ice_tm.c b/drivers/net/intel/ice/ice_tm.c
index db895613cc..ff53f2acfd 100644
--- a/drivers/net/intel/ice/ice_tm.c
+++ b/drivers/net/intel/ice/ice_tm.c
@@ -522,7 +522,8 @@ ice_tm_node_add(struct rte_eth_dev *dev, uint32_t node_id,
 	tm_node->parent->children[tm_node->parent->reference_count++] = tm_node;
 	tm_node->params = *params;
 
-	if (tm_node->priority != 0)
+	/* Priority cannot be configured for the root level */
+	if (tm_node->priority != 0 && level_id == 0)
 		PMD_DRV_LOG(WARNING, "priority != 0 not supported in level %d", level_id);
 
 	if (tm_node->weight != 1 && level_id == 0)
-- 
2.43.0

Re: [PATCH 1/3] net/ice: check for null before dereferencing

[Bruce Richardson]

On Thu, Jan 15, 2026 at 10:38:21AM +0000, Ciara Loftus wrote:
> When commiting a new Tx scheduler hierarchy we assume the user has
> created a root node. However if they have not, it leads to an invalid
> memory access. While this would be an invalid configuration by the user
> we should still prevent the invalid memory access from happening. Do so
> by ensuring the root node is non null before dereferencing.
> 
> Fixes: 715d449a965b ("net/ice: enhance Tx scheduler hierarchy support")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
> ---
Acked-by: Bruce Richardson <bruce.richardson@intel.com>

Re: [PATCH 3/3] net/ice: re-enable strict priority on non-root levels

[Bruce Richardson]

On Thu, Jan 15, 2026 at 10:38:23AM +0000, Ciara Loftus wrote:
> Commit 715d449a965b ("net/ice: enhance Tx scheduler hierarchy support")
> disabled strict priority on all levels however it will work on all
> levels except for the root level. This commit re-enables configurability
> of priority on non-root levels.
> 
> Fixes: 715d449a965b ("net/ice: enhance Tx scheduler hierarchy support")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
> ---
>  drivers/net/intel/ice/ice_tm.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
Acked-by: Bruce Richardson <bruce.richardson@intel.com>

Re: [PATCH 2/3] net/ice: fix priority mode printing in Tx scheduler dump

[Bruce Richardson]

On Thu, Jan 15, 2026 at 10:38:22AM +0000, Ciara Loftus wrote:
> A value of zero in bit 4 of the generic data means that strict priority
> is enabled. Prior to this commit it was being interpreted as WFQ being
> enabled. Fix this.
> 
> Fixes: ab4eaf9a8a31 ("net/ice: dump Tx scheduling tree")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
> ---

The relevant masks and defines are in some way badly named since the field
is therefore for enabling WFQ rather than Strict Priority. Running an AI
analysis of this block returns that the code is correct because it assumes
that the SP bit being enabled means that strict-priority is enabled (where
in datasheet the SP stands for Single Priority!)

Anyway, after checking datasheet agree fix is correct.

Acked-by: Bruce Richardson <bruce.richardson@intel.com>


>  drivers/net/intel/ice/ice_diagnose.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/intel/ice/ice_diagnose.c b/drivers/net/intel/ice/ice_diagnose.c
> index 298d1eda5c..a58279a116 100644
> --- a/drivers/net/intel/ice/ice_diagnose.c
> +++ b/drivers/net/intel/ice/ice_diagnose.c
> @@ -641,7 +641,7 @@ void print_node(const struct rte_eth_dev_data *ethdata,
>  	fprintf(stream, "\t\t\t\t<tr>\n");
>  	fprintf(stream, "\t\t\t\t\t<td> priority mode</td>\n");
>  	fprintf(stream, "\t\t\t\t\t<td>");
> -	print_priority_mode(stream, ((data->data.generic >> 4) & 0x1) != 0);
> +	print_priority_mode(stream, ((data->data.generic >> 4) & 0x1) == 0);
>  	fprintf(stream,	"</td>\n");
>  	fprintf(stream, "\t\t\t\t</tr>\n");
>  
> -- 
> 2.43.0
> 

Re: [PATCH 0/3] Ice Tx Scheduler Fixes

[Bruce Richardson]

On Thu, Jan 15, 2026 at 10:38:20AM +0000, Ciara Loftus wrote:
> Three fixes for the ice Tx Scheduler: reenable strict priority, fix debug printing and prevent a
> potential null dereference.
> 
> Ciara Loftus (3):
>   net/ice: check for null before dereferencing
>   net/ice: fix priority mode printing in Tx scheduler dump
>   net/ice: re-enable strict priority on non-root levels
>
Series applied to dpdk-next-net-intel.

Thanks,
/Bruce