[PATCH net-next v2 0/3] netdevsim: support ETS offload

[PATCH net-next v2 0/3] netdevsim: support ETS offload

[Davide Caratti]

 - patch 1 moves netdevsim tc offloads to a dedicated file
 - patch 2 enables ETS offload on netdevsim
 - patch 3 is a tdc test for ets offload on netdevsim

v2: don't use x-macro (Jakub Kicinski)

Davide Caratti (3):
  netdevsim: move TC offload code to a dedicated file
  netdevsim: support tc-ets offload
  tc-testing: add a test case for ETS offload

 drivers/net/netdevsim/Makefile                |  2 +-
 drivers/net/netdevsim/netdev.c                | 51 ------------
 drivers/net/netdevsim/netdevsim.h             |  3 +
 drivers/net/netdevsim/tc.c                    | 79 +++++++++++++++++++
 .../tc-testing/tc-tests/qdiscs/ets.json       | 23 ++++++
 5 files changed, 106 insertions(+), 52 deletions(-)
 create mode 100644 drivers/net/netdevsim/tc.c

-- 
2.52.0

[PATCH net-next v2 1/3] netdevsim: move TC offload code to a dedicated file

[Davide Caratti]

This commit has no functional change.

Signed-off-by: Davide Caratti <dcaratti@redhat.com>
---
 drivers/net/netdevsim/Makefile    |  2 +-
 drivers/net/netdevsim/netdev.c    | 51 ---------------------------
 drivers/net/netdevsim/netdevsim.h |  3 ++
 drivers/net/netdevsim/tc.c        | 57 +++++++++++++++++++++++++++++++
 4 files changed, 61 insertions(+), 52 deletions(-)
 create mode 100644 drivers/net/netdevsim/tc.c

diff --git a/drivers/net/netdevsim/Makefile b/drivers/net/netdevsim/Makefile
index 14a553e000ec..87718204fb4d 100644
--- a/drivers/net/netdevsim/Makefile
+++ b/drivers/net/netdevsim/Makefile
@@ -3,7 +3,7 @@
 obj-$(CONFIG_NETDEVSIM) += netdevsim.o
 
 netdevsim-objs := \
-	netdev.o dev.o ethtool.o fib.o bus.o health.o hwstats.o udp_tunnels.o
+	netdev.o dev.o ethtool.o fib.o bus.o health.o hwstats.o udp_tunnels.o tc.o
 
 ifeq ($(CONFIG_BPF_SYSCALL),y)
 netdevsim-objs += \
diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c
index 5ec028a00c62..1dc2f8c0695d 100644
--- a/drivers/net/netdevsim/netdev.c
+++ b/drivers/net/netdevsim/netdev.c
@@ -199,12 +199,6 @@ static int nsim_change_mtu(struct net_device *dev, int new_mtu)
 	return 0;
 }
 
-static int
-nsim_setup_tc_block_cb(enum tc_setup_type type, void *type_data, void *cb_priv)
-{
-	return nsim_bpf_setup_tc_block_cb(type, type_data, cb_priv);
-}
-
 static int nsim_set_vf_mac(struct net_device *dev, int vf, u8 *mac)
 {
 	struct netdevsim *ns = netdev_priv(dev);
@@ -335,51 +329,6 @@ static int nsim_set_vf_link_state(struct net_device *dev, int vf, int state)
 	return 0;
 }
 
-static void nsim_taprio_stats(struct tc_taprio_qopt_stats *stats)
-{
-	stats->window_drops = 0;
-	stats->tx_overruns = 0;
-}
-
-static int nsim_setup_tc_taprio(struct net_device *dev,
-				struct tc_taprio_qopt_offload *offload)
-{
-	int err = 0;
-
-	switch (offload->cmd) {
-	case TAPRIO_CMD_REPLACE:
-	case TAPRIO_CMD_DESTROY:
-		break;
-	case TAPRIO_CMD_STATS:
-		nsim_taprio_stats(&offload->stats);
-		break;
-	default:
-		err = -EOPNOTSUPP;
-	}
-
-	return err;
-}
-
-static LIST_HEAD(nsim_block_cb_list);
-
-static int
-nsim_setup_tc(struct net_device *dev, enum tc_setup_type type, void *type_data)
-{
-	struct netdevsim *ns = netdev_priv(dev);
-
-	switch (type) {
-	case TC_SETUP_QDISC_TAPRIO:
-		return nsim_setup_tc_taprio(dev, type_data);
-	case TC_SETUP_BLOCK:
-		return flow_block_cb_setup_simple(type_data,
-						  &nsim_block_cb_list,
-						  nsim_setup_tc_block_cb,
-						  ns, ns, true);
-	default:
-		return -EOPNOTSUPP;
-	}
-}
-
 static int
 nsim_set_features(struct net_device *dev, netdev_features_t features)
 {
diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index f767fc8a7505..fdd35ab29d98 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -470,3 +470,6 @@ struct nsim_bus_dev {
 
 int nsim_bus_init(void);
 void nsim_bus_exit(void);
+
+int nsim_setup_tc(struct net_device *dev, enum tc_setup_type type,
+		  void *type_data);
diff --git a/drivers/net/netdevsim/tc.c b/drivers/net/netdevsim/tc.c
new file mode 100644
index 000000000000..8a1960f5f99e
--- /dev/null
+++ b/drivers/net/netdevsim/tc.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/netdevice.h>
+#include <net/pkt_sched.h>
+
+#include "netdevsim.h"
+
+static int
+nsim_setup_tc_block_cb(enum tc_setup_type type, void *type_data, void *cb_priv)
+{
+	return nsim_bpf_setup_tc_block_cb(type, type_data, cb_priv);
+}
+
+static void nsim_taprio_stats(struct tc_taprio_qopt_stats *stats)
+{
+	stats->window_drops = 0;
+	stats->tx_overruns = 0;
+}
+
+static int nsim_setup_tc_taprio(struct net_device *dev,
+				struct tc_taprio_qopt_offload *offload)
+{
+	int err = 0;
+
+	switch (offload->cmd) {
+	case TAPRIO_CMD_REPLACE:
+	case TAPRIO_CMD_DESTROY:
+		break;
+	case TAPRIO_CMD_STATS:
+		nsim_taprio_stats(&offload->stats);
+		break;
+	default:
+		err = -EOPNOTSUPP;
+	}
+
+	return err;
+}
+
+static LIST_HEAD(nsim_block_cb_list);
+
+int
+nsim_setup_tc(struct net_device *dev, enum tc_setup_type type, void *type_data)
+{
+	struct netdevsim *ns = netdev_priv(dev);
+
+	switch (type) {
+	case TC_SETUP_QDISC_TAPRIO:
+		return nsim_setup_tc_taprio(dev, type_data);
+	case TC_SETUP_BLOCK:
+		return flow_block_cb_setup_simple(type_data,
+						  &nsim_block_cb_list,
+						  nsim_setup_tc_block_cb,
+						  ns, ns, true);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
-- 
2.52.0

Re: [PATCH net-next v2 1/3] netdevsim: move TC offload code to a dedicated file

[Jakub Kicinski]

On Fri, 13 Mar 2026 18:23:56 +0100 Davide Caratti wrote:
> diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
> index f767fc8a7505..fdd35ab29d98 100644
> --- a/drivers/net/netdevsim/netdevsim.h
> +++ b/drivers/net/netdevsim/netdevsim.h
> @@ -470,3 +470,6 @@ struct nsim_bus_dev {
>  
>  int nsim_bus_init(void);
>  void nsim_bus_exit(void);
> +
> +int nsim_setup_tc(struct net_device *dev, enum tc_setup_type type,
> +		  void *type_data);

Put this above struct nsim_bus_dev please

[PATCH net-next v2 2/3] netdevsim: support tc-ets offload

[Davide Caratti]

Extend netdevsim to accept ndo_setup_tc(TC_SETUP_QDISC_ETS) calls, so that
it's possible to run tdc on ETS offload code path.

Signed-off-by: Davide Caratti <dcaratti@redhat.com>
---
 drivers/net/netdevsim/tc.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/net/netdevsim/tc.c b/drivers/net/netdevsim/tc.c
index 8a1960f5f99e..8f013a5895a2 100644
--- a/drivers/net/netdevsim/tc.c
+++ b/drivers/net/netdevsim/tc.c
@@ -2,6 +2,7 @@
 
 #include <linux/netdevice.h>
 #include <net/pkt_sched.h>
+#include <net/pkt_cls.h>
 
 #include "netdevsim.h"
 
@@ -36,6 +37,25 @@ static int nsim_setup_tc_taprio(struct net_device *dev,
 	return err;
 }
 
+static int nsim_setup_tc_ets(struct net_device *dev,
+			     struct tc_ets_qopt_offload *offload)
+{
+	int err = 0;
+
+	switch (offload->command) {
+	case TC_ETS_REPLACE:
+	case TC_ETS_DESTROY:
+		break;
+	case TC_ETS_STATS:
+		_bstats_update(offload->stats.bstats, 0, 0);
+		break;
+	default:
+		err = -EOPNOTSUPP;
+	}
+
+	return err;
+}
+
 static LIST_HEAD(nsim_block_cb_list);
 
 int
@@ -46,6 +66,8 @@ nsim_setup_tc(struct net_device *dev, enum tc_setup_type type, void *type_data)
 	switch (type) {
 	case TC_SETUP_QDISC_TAPRIO:
 		return nsim_setup_tc_taprio(dev, type_data);
+	case TC_SETUP_QDISC_ETS:
+		return nsim_setup_tc_ets(dev, type_data);
 	case TC_SETUP_BLOCK:
 		return flow_block_cb_setup_simple(type_data,
 						  &nsim_block_cb_list,
-- 
2.52.0

[PATCH net-next v2 3/3] tc-testing: add a test case for ETS offload

[Davide Caratti]

While reviewing the fix for unintentional u32 overflows in ets offload
code, Jamal said:

 [...]

 > otherwise a tdc test should cover it fine (when you get to the
 > netdevsim change perhaps)

Add a test case to reproduce the division by zero fixed in [1].

[1] https://lore.kernel.org/all/CAM0EoMm17wsYZmdFLshH3_-GrZtzd=i0xnoO2yiVB=-N4761mw@mail.gmail.com/

Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
---
 .../tc-testing/tc-tests/qdiscs/ets.json       | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/tools/testing/selftests/tc-testing/tc-tests/qdiscs/ets.json b/tools/testing/selftests/tc-testing/tc-tests/qdiscs/ets.json
index a5d94cdec605..479b866031bb 100644
--- a/tools/testing/selftests/tc-testing/tc-tests/qdiscs/ets.json
+++ b/tools/testing/selftests/tc-testing/tc-tests/qdiscs/ets.json
@@ -984,5 +984,28 @@
         "matchCount": "1",
         "teardown": [
         ]
+    },
+    {
+        "id": "41f5",
+        "name": "ETS offload where the sum of quanta wraps u32",
+        "category": [
+            "qdisc",
+            "ets"
+        ],
+        "plugins": {
+            "requires": "nsPlugin"
+        },
+        "setup": [
+            "echo \"1 1 4\" > /sys/bus/netdevsim/new_device",
+            "ethtool -K $ETH hw-tc-offload on"
+        ],
+        "cmdUnderTest": "$TC qdisc add dev $ETH root ets quanta 4294967294 1 1",
+        "expExitCode": "0",
+        "verifyCmd": "$TC qdisc show dev $ETH",
+        "matchPattern": "qdisc ets .*bands 3 quanta 4294967294 1 1",
+        "matchCount": "1",
+        "teardown": [
+            "echo \"1\" > /sys/bus/netdevsim/del_device"
+        ]
     }
 ]
-- 
2.52.0

Re: [PATCH net-next v2 3/3] tc-testing: add a test case for ETS offload

[Victor Nogueira]

On 13/03/2026 14:23, Davide Caratti wrote:
> While reviewing the fix for unintentional u32 overflows in ets offload
> code, Jamal said:
> 
>   [...]
> 
>   > otherwise a tdc test should cover it fine (when you get to the
>   > netdevsim change perhaps)
> 
> Add a test case to reproduce the division by zero fixed in [1].
> 
> [1] https://lore.kernel.org/all/CAM0EoMm17wsYZmdFLshH3_-GrZtzd=i0xnoO2yiVB=-N4761mw@mail.gmail.com/
> 
> Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com>
> Signed-off-by: Davide Caratti <dcaratti@redhat.com>

Reviewed-by: Victor Nogueira <victor@mojatatu.com>

Re: [PATCH net-next v2 0/3] netdevsim: support ETS offload

[Jamal Hadi Salim]

On Fri, Mar 13, 2026 at 1:24 PM Davide Caratti <dcaratti@redhat.com> wrote:
>
>  - patch 1 moves netdevsim tc offloads to a dedicated file
>  - patch 2 enables ETS offload on netdevsim
>  - patch 3 is a tdc test for ets offload on netdevsim
>
> v2: don't use x-macro (Jakub Kicinski)
>
> Davide Caratti (3):
>   netdevsim: move TC offload code to a dedicated file
>   netdevsim: support tc-ets offload
>   tc-testing: add a test case for ETS offload
>
>  drivers/net/netdevsim/Makefile                |  2 +-
>  drivers/net/netdevsim/netdev.c                | 51 ------------
>  drivers/net/netdevsim/netdevsim.h             |  3 +
>  drivers/net/netdevsim/tc.c                    | 79 +++++++++++++++++++
>  .../tc-testing/tc-tests/qdiscs/ets.json       | 23 ++++++
>  5 files changed, 106 insertions(+), 52 deletions(-)
>  create mode 100644 drivers/net/netdevsim/tc.c
>

To the patchset:
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>

cheers,
jamal

> --
> 2.52.0
>

Re: [PATCH net-next v2 0/3] netdevsim: support ETS offload

[Jakub Kicinski]

On Fri, 13 Mar 2026 18:23:55 +0100 Davide Caratti wrote:
>  - patch 1 moves netdevsim tc offloads to a dedicated file
>  - patch 2 enables ETS offload on netdevsim
>  - patch 3 is a tdc test for ets offload on netdevsim

Looks like this is failing in TC CI
Is it possible that the system / container doesn't have ethtool
installed?  Adding Victor

I'll drop this from PW for now LMK if it's a TDC thing I'll restore 
it once fixed.

#  -- ns/SubPlugin.__init__
#  -- scapy/SubPlugin.__init__
# Executing 1174 tests in parallel and 88 in serial
# Using 38 batches and 4 workers
# WARNING: No route found (no default route?)
# WARNING: No route found (no default route?)
# .WARNING: more No route found (no default route?)
# ...................
# -----> prepare stage *** Could not execute: "ethtool -K $ETH hw-tc-offload on"
# 
# -----> prepare stage *** Error message: "exec of "ethtool" failed: No such file or directory
# "
# 
# -----> prepare stage *** Aborting test run.
# 
# 
# <_io.BufferedReader name=6> *** stdout ***
# 
# 
# <_io.BufferedReader name=17> *** stderr ***
#   File "/nipa-data/kernel/tools/testing/selftests/tc-testing/./tdc.py", line 535, in test_runner
#     res = run_one_test(pm, args, index, tidx)
#           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
#   File "/nipa-data/kernel/tools/testing/selftests/tc-testing/./tdc.py", line 419, in run_one_test
#     prepare_env(tidx, args, pm, 'setup', "-----> prepare stage", tidx["setup"])
#   File "/nipa-data/kernel/tools/testing/selftests/tc-testing/./tdc.py", line 267, in prepare_env
#     raise PluginMgrTestFail(
# ..........Test b438: Add basic filter with canid ematch and a combination of SFF/EFF with masks
# Test 0811: Add multiple basic filter with cmp ematch u8/link layer and default action and dump them

Re: [PATCH net-next v2 0/3] netdevsim: support ETS offload

[Victor Nogueira]

On Fri, Mar 13, 2026 at 7:11 PM Jakub Kicinski <kuba@kernel.org> wrote:
>
> On Fri, 13 Mar 2026 18:23:55 +0100 Davide Caratti wrote:
> >  - patch 1 moves netdevsim tc offloads to a dedicated file
> >  - patch 2 enables ETS offload on netdevsim
> >  - patch 3 is a tdc test for ets offload on netdevsim
>
> Looks like this is failing in TC CI
> Is it possible that the system / container doesn't have ethtool
> installed?  Adding Victor
>
> I'll drop this from PW for now LMK if it's a TDC thing I'll restore
> it once fixed.

Yes, sorry - I sent an email earlier, but just realised I forgot to cc
the list. It seems to be a TDC issue, not just the lack of ethtool,
but possibly other problems as well. I will ping you once this is
resolved.

cheers,
Victor

Re: [PATCH net-next v2 0/3] netdevsim: support ETS offload

[Victor Nogueira]

On Fri, Mar 13, 2026 at 7:47 PM Victor Nogueira <victor@mojatatu.com> wrote:
>
> On Fri, Mar 13, 2026 at 7:11 PM Jakub Kicinski <kuba@kernel.org> wrote:
> >
> > On Fri, 13 Mar 2026 18:23:55 +0100 Davide Caratti wrote:
> > >  - patch 1 moves netdevsim tc offloads to a dedicated file
> > >  - patch 2 enables ETS offload on netdevsim
> > >  - patch 3 is a tdc test for ets offload on netdevsim
> >
> > Looks like this is failing in TC CI
> > Is it possible that the system / container doesn't have ethtool
> > installed?  Adding Victor
> >
> > I'll drop this from PW for now LMK if it's a TDC thing I'll restore
> > it once fixed.
>
> It seems to be a TDC issue [...]
> I will ping you once this is resolved

Should be safe to restore the patch now.

cheers,
Victor