[PATCH net-next V6 0/4] devlink: Add boot-time eswitch mode defaults

[PATCH net-next V6 0/4] devlink: Add boot-time eswitch mode defaults

[Mark Bloch]

This series adds a devlink_eswitch_mode= kernel command line parameter
for setting a default devlink eswitch mode during boot.

Following the discussion with Jakub[1] and the feedback on the RFC
postings, this version keeps the scope limited to a boot-time devlink
eswitch mode default only.

The option selects either all devlink handles or an explicit
comma-separated handle list:

devlink_eswitch_mode=*=switchdev
devlink_eswitch_mode=pci/0000:08:00.0,pci/0000:09:00.1=switchdev_inactive

The supported modes are legacy, switchdev and switchdev_inactive. The
selected mode is applied through the existing eswitch_mode_set() devlink
operation, the same operation used by the devlink eswitch mode command.

Registration may happen while a driver holds the devlink lock and
continues device initialization. Devlink core marks the default as
pending and applies it from devl_unlock() once the instance is
registered, before releasing the lock. This prevents userspace from
racing with the boot default.

After a successful reload that performed DRIVER_REINIT, devlink core
already holds the devlink instance lock and the driver completed
reload_up(), so the default is applied directly from the reload path.

Patch 1 clears the mlx5 FW reset-in-progress bit before reload.

Patch 2 factors the common eswitch mode set validation into a helper.

Patch 3 adds the devlink_eswitch_mode= parser and documentation.

Patch 4 applies parsed defaults from devlink core.

Changelog:

v5 -> v6:

- Dropped regular work and applied a pending default directly from
  devl_unlock() while the devlink instance lock is still held.

- Dropped the driver API and mlx5-specific default application patches.

v4 -> v5:

- Moved the default eswitch mode code into a separate file, per Jiri's
  comment.

- Dropped the delayed workqueue and switched to regular work triggered
  via devl_unlock(), per Jiri's comment.

- Renamed some functions to better align with devlink code.

v3 -> v4:

- Rework registration time apply to use per devlink work queued from
  devl_unlock(), instead of calling eswitch_mode_set() directly from
  devl_register().

- Apply the default directly after successful DRIVER_REINIT devlink reload,
  where the devlink lock is already held and reload_up() has completed.

- Add devl_apply_default_esw_mode() for drivers that know their exact ready
  point.

- Drop the driver registration-ordering preparation patches that are no
  longer needed with the async registration apply path.

v2 -> v3:

- Change the devlink_eswitch_mode= API syntax to use <selector>=<mode>
  instead of [<selector>]:<mode>, following a comment from Randy Dunlap.

v1 -> v2:

- Move default eswitch mode application into devlink core. The default is
  now applied during devlink registration and after a successful devlink
  reload that performed DRIVER_REINIT.

- Remove the exported devl_apply_default_esw_mode() driver API and the mlx5
  driver-side call to it.

- Skip devlink health recovery notifications while the devlink instance is
  not registered, so drivers can move registration later without early
  health work hitting registration assertions.

- Move mlx5 devlink registration after device initialization, including the
  lightweight init path, so the core can apply the default through the
  normal registration flow.

- Move the matching netdevsim and mlx5 unregister paths before object
  teardown, so unregister notifications come from devl_unregister() and the
  later object teardown paths run while the devlink instance is no longer
  registered.

- Add registration-ordering preparation patches for netdevsim and octeontx2
  AF/PF, so their eswitch state is ready before registration-time defaults
  may call eswitch_mode_set().

[1] lore.kernel.org/r/20260502184153.4fd8d06f@kernel.org/
RFC v1: lore.kernel.org/r/20260506123739.1959770-1-mbloch@nvidia.com/
RFC v2: lore.kernel.org/r/20260510185424.2041415-1-mbloch@nvidia.com/
v1: lore.kernel.org/r/20260521072434.362624-1-tariqt@nvidia.com/
v2: lore.kernel.org/all/20260603193259.3412464-1-mbloch@nvidia.com/
v3: lore.kernel.org/all/20260605181030.3486619-1-mbloch@nvidia.com/
v4: lore.kernel.org/all/20260629182102.245150-1-mbloch@nvidia.com/
v5: lore.kernel.org/all/20260707174527.425134-1-mbloch@nvidia.com/

Mark Bloch (4):
  net/mlx5: Clear FW reset-in-progress bit before reload
  devlink: Factor out eswitch mode setting
  devlink: Parse eswitch mode boot defaults
  devlink: Apply eswitch mode boot defaults

 .../admin-guide/kernel-parameters.txt         |  25 ++
 .../networking/devlink/devlink-defaults.rst   |  78 +++++
 Documentation/networking/devlink/index.rst    |   1 +
 .../ethernet/mellanox/mlx5/core/fw_reset.c    |  28 +-
 net/devlink/Makefile                          |   2 +-
 net/devlink/core.c                            |  10 +
 net/devlink/default.c                         | 303 ++++++++++++++++++
 net/devlink/dev.c                             |  33 +-
 net/devlink/devl_internal.h                   |  10 +
 9 files changed, 471 insertions(+), 19 deletions(-)
 create mode 100644 Documentation/networking/devlink/devlink-defaults.rst
 create mode 100644 net/devlink/default.c


base-commit: f6f3b36c15ed44de1fbb44e645e4fae8c4a4453e
-- 
2.43.0

[PATCH net-next V6 1/4] net/mlx5: Clear FW reset-in-progress bit before reload

[Mark Bloch]

mlx5 sets MLX5_FW_RESET_FLAGS_RESET_IN_PROGRESS when acknowledging a sync
reset request. This bit blocks devlink reload and other devlink operations
while the firmware reset is running, but it was kept set until after the
driver reload finished.

Clear the reset-in-progress bit once the reset unload flow is done and PCI
access is back, before reloading the device. For a reset initiated through
devlink, clear it before completing the reload waiter. For a reset reported
through an asynchronous firmware event, keep the unload flow outside
devl_lock, then take devl_lock before clearing the bit and reloading
through the devl-locked load helper.

Reviewed-by: Shay Drori <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
---
 .../ethernet/mellanox/mlx5/core/fw_reset.c    | 28 +++++++++++--------
 1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c
index 07440c58713a..7283e5b49eed 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c
@@ -238,24 +238,30 @@ static void mlx5_fw_reset_complete_reload(struct mlx5_core_dev *dev)
 {
 	struct mlx5_fw_reset *fw_reset = dev->priv.fw_reset;
 	struct devlink *devlink = priv_to_devlink(dev);
+	int err;
 
 	/* if this is the driver that initiated the fw reset, devlink completed the reload */
 	if (test_bit(MLX5_FW_RESET_FLAGS_PENDING_COMP, &fw_reset->reset_flags)) {
+		clear_bit(MLX5_FW_RESET_FLAGS_RESET_IN_PROGRESS,
+			  &fw_reset->reset_flags);
 		complete(&fw_reset->done);
-	} else {
-		mlx5_sync_reset_unload_flow(dev, false);
-		if (mlx5_health_wait_pci_up(dev))
-			mlx5_core_err(dev, "reset reload flow aborted, PCI reads still not working\n");
-		else
-			mlx5_load_one(dev, true);
-		devl_lock(devlink);
-		devlink_remote_reload_actions_performed(devlink, 0,
-							BIT(DEVLINK_RELOAD_ACTION_DRIVER_REINIT) |
-							BIT(DEVLINK_RELOAD_ACTION_FW_ACTIVATE));
-		devl_unlock(devlink);
+		return;
 	}
 
+	mlx5_sync_reset_unload_flow(dev, false);
+	err = mlx5_health_wait_pci_up(dev);
+
+	devl_lock(devlink);
 	clear_bit(MLX5_FW_RESET_FLAGS_RESET_IN_PROGRESS, &fw_reset->reset_flags);
+	if (err)
+		mlx5_core_err(dev, "reset reload flow aborted, PCI reads still not working\n");
+	else
+		mlx5_load_one_devl_locked(dev, true);
+
+	devlink_remote_reload_actions_performed(devlink, 0,
+						BIT(DEVLINK_RELOAD_ACTION_DRIVER_REINIT) |
+						BIT(DEVLINK_RELOAD_ACTION_FW_ACTIVATE));
+	devl_unlock(devlink);
 }
 
 static void mlx5_stop_sync_reset_poll(struct mlx5_core_dev *dev)
-- 
2.43.0

[PATCH net-next V6 2/4] devlink: Factor out eswitch mode setting

[Mark Bloch]

Move the common eswitch mode set checks into a small helper and use it
from the netlink eswitch set command. This makes the same validation
available to the devlink core path that applies eswitch mode defaults.

Signed-off-by: Mark Bloch <mbloch@nvidia.com>
---
 net/devlink/dev.c           | 27 ++++++++++++++++++++-------
 net/devlink/devl_internal.h |  3 +++
 2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/net/devlink/dev.c b/net/devlink/dev.c
index bcf001554e84..119ef105d0a7 100644
--- a/net/devlink/dev.c
+++ b/net/devlink/dev.c
@@ -702,6 +702,25 @@ int devlink_nl_eswitch_get_doit(struct sk_buff *skb, struct genl_info *info)
 	return genlmsg_reply(msg, info);
 }
 
+int devlink_eswitch_mode_set(struct devlink *devlink,
+			     enum devlink_eswitch_mode mode,
+			     struct netlink_ext_ack *extack)
+{
+	const struct devlink_ops *ops = devlink->ops;
+	int err;
+
+	devl_assert_locked(devlink);
+
+	if (!ops->eswitch_mode_set)
+		return -EOPNOTSUPP;
+
+	err = devlink_rates_check(devlink, devlink_rate_is_node, extack);
+	if (err)
+		return err;
+
+	return ops->eswitch_mode_set(devlink, mode, extack);
+}
+
 int devlink_nl_eswitch_set_doit(struct sk_buff *skb, struct genl_info *info)
 {
 	struct devlink *devlink = devlink_nl_ctx(info)->devlink;
@@ -712,14 +731,8 @@ int devlink_nl_eswitch_set_doit(struct sk_buff *skb, struct genl_info *info)
 	u16 mode;
 
 	if (info->attrs[DEVLINK_ATTR_ESWITCH_MODE]) {
-		if (!ops->eswitch_mode_set)
-			return -EOPNOTSUPP;
-		err = devlink_rates_check(devlink, devlink_rate_is_node,
-					  info->extack);
-		if (err)
-			return err;
 		mode = nla_get_u16(info->attrs[DEVLINK_ATTR_ESWITCH_MODE]);
-		err = ops->eswitch_mode_set(devlink, mode, info->extack);
+		err = devlink_eswitch_mode_set(devlink, mode, info->extack);
 		if (err)
 			return err;
 	}
diff --git a/net/devlink/devl_internal.h b/net/devlink/devl_internal.h
index cdf894ba5a9d..af43b7163f78 100644
--- a/net/devlink/devl_internal.h
+++ b/net/devlink/devl_internal.h
@@ -348,6 +348,9 @@ bool devlink_rate_is_node(const struct devlink_rate *devlink_rate);
 int devlink_rates_check(struct devlink *devlink,
 			bool (*rate_filter)(const struct devlink_rate *),
 			struct netlink_ext_ack *extack);
+int devlink_eswitch_mode_set(struct devlink *devlink,
+			     enum devlink_eswitch_mode mode,
+			     struct netlink_ext_ack *extack);
 
 /* Linecards */
 unsigned int devlink_linecard_index(struct devlink_linecard *linecard);
-- 
2.43.0

[PATCH net-next V6 3/4] devlink: Parse eswitch mode boot defaults

[Mark Bloch]

Add devlink_eswitch_mode= kernel command line parsing for a default
eswitch mode.

The supported syntax selects either all devlink handles or one explicit
comma-separated handle list:

  devlink_eswitch_mode=*=<mode>

  devlink_eswitch_mode=<handle>[,<handle>...]=<mode>

where <mode> is one of legacy, switchdev or switchdev_inactive. All
selected handles receive the same mode. Assigning different modes to
different handle lists in the same parameter value is not supported.

Store the parsed selector and mode in devlink core so the default can be
applied by a downstream patch.

Document the devlink_eswitch_mode= syntax and duplicate handle handling.

Signed-off-by: Mark Bloch <mbloch@nvidia.com>
---
 .../admin-guide/kernel-parameters.txt         |  25 ++
 .../networking/devlink/devlink-defaults.rst   |  78 ++++++
 Documentation/networking/devlink/index.rst    |   1 +
 net/devlink/Makefile                          |   2 +-
 net/devlink/core.c                            |   7 +
 net/devlink/default.c                         | 237 ++++++++++++++++++
 net/devlink/devl_internal.h                   |   2 +
 7 files changed, 351 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/networking/devlink/devlink-defaults.rst
 create mode 100644 net/devlink/default.c

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index b5493a7f8f22..117300dd589c 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1249,6 +1249,31 @@ Kernel parameters
 	dell_smm_hwmon.fan_max=
 			[HW] Maximum configurable fan speed.
 
+	devlink_eswitch_mode=
+			[NET]
+			Format:
+			<selector>=<mode>
+
+			<selector>:
+			* | <handle>[,<handle>...]
+
+			<handle>:
+			<bus-name>/<dev-name>
+
+			Configure default devlink eswitch mode for matching
+			devlink instances during device initialization.
+
+			<mode>:
+			legacy | switchdev | switchdev_inactive
+
+			Examples:
+			devlink_eswitch_mode=*=switchdev
+			devlink_eswitch_mode=pci/0000:08:00.0=switchdev
+			devlink_eswitch_mode=pci/0000:08:00.0,pci/0000:09:00.1=switchdev_inactive
+
+			See Documentation/networking/devlink/devlink-defaults.rst
+			for the full syntax.
+
 	dfltcc=		[HW,S390]
 			Format: { on | off | def_only | inf_only | always }
 			on:       s390 zlib hardware support for compression on
diff --git a/Documentation/networking/devlink/devlink-defaults.rst b/Documentation/networking/devlink/devlink-defaults.rst
new file mode 100644
index 000000000000..380c9e99210e
--- /dev/null
+++ b/Documentation/networking/devlink/devlink-defaults.rst
@@ -0,0 +1,78 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==============================
+Devlink Eswitch Mode Defaults
+==============================
+
+Devlink eswitch mode defaults allow the eswitch mode to be provided on the
+kernel command line and applied to matching devlink instances during device
+initialization.
+
+The devlink device is selected by its devlink handle. For PCI devices this is
+the same handle shown by ``devlink dev show``, for example
+``pci/0000:08:00.0``.
+
+Kernel command line syntax
+==========================
+
+Defaults are specified with the ``devlink_eswitch_mode=`` kernel command line
+parameter.
+
+The general syntax is::
+
+  devlink_eswitch_mode=<selector>=<mode>
+
+``<selector>`` is either ``*`` or one or more devlink handles::
+
+  * | <bus-name>/<dev-name>[,<bus-name>/<dev-name>...]
+
+``*`` applies the mode to every devlink instance. All handles in the same
+selector receive the same eswitch mode.
+
+``<mode>`` is one of ``legacy``, ``switchdev`` or ``switchdev_inactive``.
+
+Syntax rules
+------------
+
+The following syntax rules apply:
+
+* Specify the default in one ``devlink_eswitch_mode=`` parameter. Repeated
+  ``devlink_eswitch_mode=`` parameters are not accumulated.
+* The ``devlink_eswitch_mode=`` value is limited by the kernel command line
+  size.
+* Whitespace is not allowed within the parameter value.
+* ``<selector>`` must be either ``*`` or a handle list. ``*`` cannot be
+  combined with explicit handles.
+* ``<bus-name>`` and ``<dev-name>`` must not be empty.
+* ``<dev-name>`` may contain ``:``. This allows PCI names such as
+  ``0000:08:00.0``.
+* Handles must not contain whitespace, ``*``, ``=`` or more than one ``/``.
+* A comma separates handles.
+* Comma-separated default assignments are not supported.
+* Duplicate handles are rejected and the devlink eswitch mode default is
+  ignored.
+
+The eswitch mode default corresponds to the userspace command::
+
+  devlink dev eswitch set <handle> mode <value>
+
+
+Examples
+========
+
+Set all devlink instances to switchdev mode::
+
+  devlink_eswitch_mode=*=switchdev
+
+Set one PCI devlink instance to switchdev mode::
+
+  devlink_eswitch_mode=pci/0000:08:00.0=switchdev
+
+Set two PCI devlink instances to switchdev inactive mode::
+
+  devlink_eswitch_mode=pci/0000:08:00.0,pci/0000:09:00.1=switchdev_inactive
+
+The following is invalid because comma-separated default assignments are not
+supported::
+
+  devlink_eswitch_mode=pci/0000:08:00.0=switchdev,pci/0000:09:00.0=switchdev_inactive
diff --git a/Documentation/networking/devlink/index.rst b/Documentation/networking/devlink/index.rst
index 4745148fecf4..134d2f319922 100644
--- a/Documentation/networking/devlink/index.rst
+++ b/Documentation/networking/devlink/index.rst
@@ -56,6 +56,7 @@ general.
    :maxdepth: 1
 
    devlink-dpipe
+   devlink-defaults
    devlink-eswitch-attr
    devlink-flash
    devlink-health
diff --git a/net/devlink/Makefile b/net/devlink/Makefile
index 8f2adb5e5836..99ca0ef7cf1e 100644
--- a/net/devlink/Makefile
+++ b/net/devlink/Makefile
@@ -1,4 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
 
-obj-y := core.o netlink.o netlink_gen.o dev.o port.o sb.o dpipe.o \
+obj-y := core.o netlink.o netlink_gen.o dev.o default.o port.o sb.o dpipe.o \
 	 resource.o param.o region.o health.o trap.o rate.o linecard.o sh_dev.o
diff --git a/net/devlink/core.c b/net/devlink/core.c
index c53a42e17a58..fc14ee5d9dcf 100644
--- a/net/devlink/core.c
+++ b/net/devlink/core.c
@@ -598,6 +598,10 @@ static int __init devlink_init(void)
 {
 	int err;
 
+	err = devlink_default_esw_mode_init();
+	if (err)
+		goto out;
+
 	err = register_pernet_subsys(&devlink_pernet_ops);
 	if (err)
 		goto out;
@@ -613,7 +617,10 @@ static int __init devlink_init(void)
 out_unreg_pernet_subsys:
 	unregister_pernet_subsys(&devlink_pernet_ops);
 out:
+	if (err)
+		devlink_default_esw_mode_cleanup();
 	WARN_ON(err);
+
 	return err;
 }
 
diff --git a/net/devlink/default.c b/net/devlink/default.c
new file mode 100644
index 000000000000..8434af83ea69
--- /dev/null
+++ b/net/devlink/default.c
@@ -0,0 +1,237 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved. */
+
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+#include "devl_internal.h"
+
+static char *devlink_default_esw_mode_param;
+static bool devlink_default_esw_mode_match_all;
+static enum devlink_eswitch_mode devlink_default_esw_mode;
+static LIST_HEAD(devlink_default_esw_mode_nodes);
+
+struct devlink_default_esw_mode_node {
+	struct list_head list;
+	char *bus_name;
+	char *dev_name;
+};
+
+static int __init
+devlink_default_esw_mode_to_value(const char *str,
+				  enum devlink_eswitch_mode *mode)
+{
+	if (!strcmp(str, "legacy")) {
+		*mode = DEVLINK_ESWITCH_MODE_LEGACY;
+		return 0;
+	}
+	if (!strcmp(str, "switchdev")) {
+		*mode = DEVLINK_ESWITCH_MODE_SWITCHDEV;
+		return 0;
+	}
+	if (!strcmp(str, "switchdev_inactive")) {
+		*mode = DEVLINK_ESWITCH_MODE_SWITCHDEV_INACTIVE;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int __init
+devlink_default_esw_mode_handle_parse(char *handle, char **bus_name,
+				      char **dev_name)
+{
+	char *slash;
+	char *p;
+
+	if (!*handle)
+		return -EINVAL;
+
+	for (p = handle; *p; p++) {
+		if (*p == '*' || *p == '=')
+			return -EINVAL;
+	}
+
+	slash = strchr(handle, '/');
+	if (!slash || slash == handle || !slash[1])
+		return -EINVAL;
+	if (strchr(slash + 1, '/'))
+		return -EINVAL;
+
+	*slash = '\0';
+
+	*bus_name = handle;
+	*dev_name = slash + 1;
+	return 0;
+}
+
+static struct devlink_default_esw_mode_node *
+devlink_default_esw_mode_node_find(const char *bus_name, const char *dev_name)
+{
+	struct devlink_default_esw_mode_node *node;
+
+	list_for_each_entry(node, &devlink_default_esw_mode_nodes, list) {
+		if (!strcmp(node->bus_name, bus_name) &&
+		    !strcmp(node->dev_name, dev_name))
+			return node;
+	}
+
+	return NULL;
+}
+
+static int __init
+devlink_default_esw_mode_node_add(const char *bus_name, const char *dev_name)
+{
+	struct devlink_default_esw_mode_node *node;
+
+	if (devlink_default_esw_mode_node_find(bus_name, dev_name))
+		return -EEXIST;
+
+	node = kzalloc_obj(*node);
+	if (!node)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&node->list);
+	node->bus_name = kstrdup(bus_name, GFP_KERNEL);
+	node->dev_name = kstrdup(dev_name, GFP_KERNEL);
+	if (!node->bus_name || !node->dev_name) {
+		kfree(node->bus_name);
+		kfree(node->dev_name);
+		kfree(node);
+		return -ENOMEM;
+	}
+
+	list_add_tail(&node->list, &devlink_default_esw_mode_nodes);
+	return 0;
+}
+
+static int __init devlink_default_esw_mode_handles_parse(char *handles)
+{
+	char *handle;
+	int err;
+
+	if (!strcmp(handles, "*")) {
+		devlink_default_esw_mode_match_all = true;
+		return 0;
+	}
+
+	while ((handle = strsep(&handles, ",")) != NULL) {
+		char *bus_name;
+		char *dev_name;
+
+		err = devlink_default_esw_mode_handle_parse(handle, &bus_name,
+							    &dev_name);
+		if (err)
+			return err;
+
+		err = devlink_default_esw_mode_node_add(bus_name, dev_name);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static void __init
+devlink_default_esw_mode_node_free(struct devlink_default_esw_mode_node *node)
+{
+	kfree(node->bus_name);
+	kfree(node->dev_name);
+	kfree(node);
+}
+
+static void __init devlink_default_esw_mode_nodes_clear(void)
+{
+	struct devlink_default_esw_mode_node *node_tmp;
+	struct devlink_default_esw_mode_node *node;
+
+	list_for_each_entry_safe(node, node_tmp,
+				 &devlink_default_esw_mode_nodes, list) {
+		list_del(&node->list);
+		devlink_default_esw_mode_node_free(node);
+	}
+
+	devlink_default_esw_mode_match_all = false;
+}
+
+static int __init devlink_default_esw_mode_parse(char *str)
+{
+	enum devlink_eswitch_mode esw_mode;
+	char *separator;
+	char *handles;
+	char *mode;
+	int err;
+
+	if (!*str)
+		return -EINVAL;
+
+	separator = strrchr(str, '=');
+	if (!separator || separator == str || !separator[1])
+		return -EINVAL;
+
+	*separator = '\0';
+	handles = str;
+	mode = separator + 1;
+
+	err = devlink_default_esw_mode_to_value(mode, &esw_mode);
+	if (err)
+		return err;
+
+	err = devlink_default_esw_mode_handles_parse(handles);
+	if (err)
+		devlink_default_esw_mode_nodes_clear();
+	else
+		devlink_default_esw_mode = esw_mode;
+
+	return err;
+}
+
+static int __init devlink_default_esw_mode_setup(char *str)
+{
+	devlink_default_esw_mode_param = str;
+	return 1;
+}
+__setup("devlink_eswitch_mode=", devlink_default_esw_mode_setup);
+
+int __init devlink_default_esw_mode_init(void)
+{
+	char *def;
+	int err;
+
+	if (!devlink_default_esw_mode_param)
+		return 0;
+
+	def = kstrdup(devlink_default_esw_mode_param, GFP_KERNEL);
+	if (!def) {
+		devlink_default_esw_mode_param = NULL;
+		pr_warn("devlink: devlink_eswitch_mode parameter ignored, failed to allocate memory\n");
+		return 0;
+	}
+
+	err = devlink_default_esw_mode_parse(def);
+	kfree(def);
+	if (err == -EEXIST) {
+		devlink_default_esw_mode_param = NULL;
+		pr_warn("devlink: duplicate eswitch mode handles ignored\n");
+		return 0;
+	} else if (err == -EINVAL) {
+		devlink_default_esw_mode_param = NULL;
+		pr_warn("devlink: invalid devlink_eswitch_mode parameter ignored\n");
+		return 0;
+	} else if (err == -ENOMEM) {
+		devlink_default_esw_mode_param = NULL;
+		pr_warn("devlink: devlink_eswitch_mode parameter ignored, failed to allocate memory\n");
+		return 0;
+	} else if (err) {
+		return err;
+	}
+
+	return 0;
+}
+
+void __init devlink_default_esw_mode_cleanup(void)
+{
+	devlink_default_esw_mode_nodes_clear();
+}
diff --git a/net/devlink/devl_internal.h b/net/devlink/devl_internal.h
index af43b7163f78..fe9ad58515d4 100644
--- a/net/devlink/devl_internal.h
+++ b/net/devlink/devl_internal.h
@@ -71,6 +71,8 @@ extern struct genl_family devlink_nl_family;
 struct devlink *__devlink_alloc(const struct devlink_ops *ops, size_t priv_size,
 				struct net *net, struct device *dev,
 				const struct device_driver *dev_driver);
+int devlink_default_esw_mode_init(void);
+void devlink_default_esw_mode_cleanup(void);
 
 #define devl_warn(devlink, format, args...)				\
 	do {								\
-- 
2.43.0

[PATCH net-next V6 4/4] devlink: Apply eswitch mode boot defaults

[Mark Bloch]

Apply parsed devlink_eswitch_mode= defaults after devlink registration
and after successful reload.

Mark the default mode as pending when a devlink instance is allocated.
Before devl_unlock() releases the instance lock, apply a pending default
when the instance is registered.

Clear the pending state before calling into the driver so the boot
default remains a one-shot operation even if the mode change fails.

For successful reloads that performed DRIVER_REINIT, devlink_reload()
already holds the devlink instance lock and the driver has completed
reload_up(). Clear the pending state and apply the default directly from
the reload path.

Treat an explicit user eswitch mode request as consuming the pending
default mode.

Signed-off-by: Mark Bloch <mbloch@nvidia.com>
---
 net/devlink/core.c          |  3 ++
 net/devlink/default.c       | 70 +++++++++++++++++++++++++++++++++++--
 net/devlink/dev.c           |  6 ++++
 net/devlink/devl_internal.h |  5 +++
 4 files changed, 82 insertions(+), 2 deletions(-)

diff --git a/net/devlink/core.c b/net/devlink/core.c
index fc14ee5d9dcf..cea4afc27dd9 100644
--- a/net/devlink/core.c
+++ b/net/devlink/core.c
@@ -317,6 +317,7 @@ EXPORT_SYMBOL_GPL(devl_trylock);
 
 void devl_unlock(struct devlink *devlink)
 {
+	devlink_default_esw_mode_apply_pending(devlink);
 	mutex_unlock(&devlink->lock);
 }
 EXPORT_SYMBOL_GPL(devl_unlock);
@@ -429,6 +430,7 @@ void devl_unregister(struct devlink *devlink)
 	ASSERT_DEVLINK_REGISTERED(devlink);
 	devl_assert_locked(devlink);
 
+	devlink_default_esw_mode_apply_pending_clear(devlink);
 	devlink_notify_unregister(devlink);
 	xa_clear_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
 	devlink_rel_put(devlink);
@@ -490,6 +492,7 @@ struct devlink *__devlink_alloc(const struct devlink_ops *ops, size_t priv_size,
 	INIT_LIST_HEAD(&devlink->trap_group_list);
 	INIT_LIST_HEAD(&devlink->trap_policer_list);
 	INIT_RCU_WORK(&devlink->rwork, devlink_release);
+	devlink_default_esw_mode_instance_init(devlink);
 	lockdep_register_key(&devlink->lock_key);
 	mutex_init(&devlink->lock);
 	lockdep_set_class(&devlink->lock, &devlink->lock_key);
diff --git a/net/devlink/default.c b/net/devlink/default.c
index 8434af83ea69..77cc356dfac9 100644
--- a/net/devlink/default.c
+++ b/net/devlink/default.c
@@ -10,6 +10,7 @@
 
 static char *devlink_default_esw_mode_param;
 static bool devlink_default_esw_mode_match_all;
+static bool devlink_default_esw_mode_enabled;
 static enum devlink_eswitch_mode devlink_default_esw_mode;
 static LIST_HEAD(devlink_default_esw_mode_nodes);
 
@@ -154,6 +155,7 @@ static void __init devlink_default_esw_mode_nodes_clear(void)
 	}
 
 	devlink_default_esw_mode_match_all = false;
+	devlink_default_esw_mode_enabled = false;
 }
 
 static int __init devlink_default_esw_mode_parse(char *str)
@@ -180,14 +182,78 @@ static int __init devlink_default_esw_mode_parse(char *str)
 		return err;
 
 	err = devlink_default_esw_mode_handles_parse(handles);
-	if (err)
+	if (err) {
 		devlink_default_esw_mode_nodes_clear();
-	else
+	} else {
 		devlink_default_esw_mode = esw_mode;
+		devlink_default_esw_mode_enabled = true;
+	}
 
 	return err;
 }
 
+static bool devlink_default_esw_mode_match(struct devlink *devlink)
+{
+	const char *bus_name = devlink_bus_name(devlink);
+	const char *dev_name = devlink_dev_name(devlink);
+	struct devlink_default_esw_mode_node *node;
+
+	if (devlink_default_esw_mode_match_all)
+		return true;
+
+	node = devlink_default_esw_mode_node_find(bus_name, dev_name);
+	return !!node;
+}
+
+void devlink_default_esw_mode_apply_locked(struct devlink *devlink)
+{
+	const struct devlink_ops *ops = devlink->ops;
+	int err;
+
+	devl_assert_locked(devlink);
+
+	if (!devlink_default_esw_mode_match(devlink))
+		return;
+
+	if (!ops->eswitch_mode_set) {
+		if (!devlink_default_esw_mode_match_all)
+			devl_warn(devlink,
+				  "devlink_eswitch_mode= selected this device but eswitch mode setting is not supported\n");
+		return;
+	}
+
+	err = devlink_eswitch_mode_set(devlink, devlink_default_esw_mode, NULL);
+	if (err)
+		devl_warn(devlink,
+			  "Couldn't apply default eswitch mode, err %d\n",
+			  err);
+}
+
+void devlink_default_esw_mode_apply_pending(struct devlink *devlink)
+{
+	devl_assert_locked(devlink);
+
+	if (!devlink->default_esw_mode_apply_pending ||
+	    !__devl_is_registered(devlink))
+		return;
+
+	devlink->default_esw_mode_apply_pending = false;
+	devlink_default_esw_mode_apply_locked(devlink);
+}
+
+void devlink_default_esw_mode_instance_init(struct devlink *devlink)
+{
+	devlink->default_esw_mode_apply_pending =
+		devlink_default_esw_mode_enabled;
+}
+
+void devlink_default_esw_mode_apply_pending_clear(struct devlink *devlink)
+{
+	devl_assert_locked(devlink);
+
+	devlink->default_esw_mode_apply_pending = false;
+}
+
 static int __init devlink_default_esw_mode_setup(char *str)
 {
 	devlink_default_esw_mode_param = str;
diff --git a/net/devlink/dev.c b/net/devlink/dev.c
index 119ef105d0a7..611bb6bfd492 100644
--- a/net/devlink/dev.c
+++ b/net/devlink/dev.c
@@ -478,6 +478,11 @@ int devlink_reload(struct devlink *devlink, struct net *dest_net,
 		return err;
 
 	WARN_ON(!(*actions_performed & BIT(action)));
+	if (*actions_performed & BIT(DEVLINK_RELOAD_ACTION_DRIVER_REINIT)) {
+		devlink_default_esw_mode_apply_pending_clear(devlink);
+		devlink_default_esw_mode_apply_locked(devlink);
+	}
+
 	/* Catch driver on updating the remote action within devlink reload */
 	WARN_ON(memcmp(remote_reload_stats, devlink->stats.remote_reload_stats,
 		       sizeof(remote_reload_stats)));
@@ -731,6 +736,7 @@ int devlink_nl_eswitch_set_doit(struct sk_buff *skb, struct genl_info *info)
 	u16 mode;
 
 	if (info->attrs[DEVLINK_ATTR_ESWITCH_MODE]) {
+		devlink_default_esw_mode_apply_pending_clear(devlink);
 		mode = nla_get_u16(info->attrs[DEVLINK_ATTR_ESWITCH_MODE]);
 		err = devlink_eswitch_mode_set(devlink, mode, info->extack);
 		if (err)
diff --git a/net/devlink/devl_internal.h b/net/devlink/devl_internal.h
index fe9ad58515d4..97f53394b1c0 100644
--- a/net/devlink/devl_internal.h
+++ b/net/devlink/devl_internal.h
@@ -58,6 +58,7 @@ struct devlink {
 	struct mutex lock;
 	struct lock_class_key lock_key;
 	u8 reload_failed:1;
+	u8 default_esw_mode_apply_pending:1;
 	refcount_t refcount;
 	struct rcu_work rwork;
 	struct devlink_rel *rel;
@@ -73,6 +74,10 @@ struct devlink *__devlink_alloc(const struct devlink_ops *ops, size_t priv_size,
 				const struct device_driver *dev_driver);
 int devlink_default_esw_mode_init(void);
 void devlink_default_esw_mode_cleanup(void);
+void devlink_default_esw_mode_instance_init(struct devlink *devlink);
+void devlink_default_esw_mode_apply_locked(struct devlink *devlink);
+void devlink_default_esw_mode_apply_pending(struct devlink *devlink);
+void devlink_default_esw_mode_apply_pending_clear(struct devlink *devlink);
 
 #define devl_warn(devlink, format, args...)				\
 	do {								\
-- 
2.43.0

Re: [PATCH net-next V6 4/4] devlink: Apply eswitch mode boot defaults

[Jiri Pirko]

Tue, Jul 14, 2026 at 08:17:30AM +0200, mbloch@nvidia.com wrote:
>Apply parsed devlink_eswitch_mode= defaults after devlink registration
>and after successful reload.
>
>Mark the default mode as pending when a devlink instance is allocated.
>Before devl_unlock() releases the instance lock, apply a pending default
>when the instance is registered.
>
>Clear the pending state before calling into the driver so the boot
>default remains a one-shot operation even if the mode change fails.
>
>For successful reloads that performed DRIVER_REINIT, devlink_reload()
>already holds the devlink instance lock and the driver has completed
>reload_up(). Clear the pending state and apply the default directly from
>the reload path.
>
>Treat an explicit user eswitch mode request as consuming the pending
>default mode.
>

Looks fine to me now. One nit below:


[..]

>+void devlink_default_esw_mode_instance_init(struct devlink *devlink)


Forgotten "instance" here. With this fixed, feel free to add my
Reviewed-by: Jiri Pirko <jiri@nvidia.com>

[..]

Re: [PATCH net-next V6 3/4] devlink: Parse eswitch mode boot defaults

[Jiri Pirko]

Tue, Jul 14, 2026 at 08:17:29AM +0200, mbloch@nvidia.com wrote:
>Add devlink_eswitch_mode= kernel command line parsing for a default
>eswitch mode.
>
>The supported syntax selects either all devlink handles or one explicit
>comma-separated handle list:
>
>  devlink_eswitch_mode=*=<mode>
>
>  devlink_eswitch_mode=<handle>[,<handle>...]=<mode>
>
>where <mode> is one of legacy, switchdev or switchdev_inactive. All
>selected handles receive the same mode. Assigning different modes to
>different handle lists in the same parameter value is not supported.
>
>Store the parsed selector and mode in devlink core so the default can be
>applied by a downstream patch.
>
>Document the devlink_eswitch_mode= syntax and duplicate handle handling.
>
>Signed-off-by: Mark Bloch <mbloch@nvidia.com>

Reviewed-by: Jiri Pirko <jiri@nvidia.com>

Re: [PATCH net-next V6 2/4] devlink: Factor out eswitch mode setting

[Jiri Pirko]

Tue, Jul 14, 2026 at 08:17:28AM +0200, mbloch@nvidia.com wrote:
>Move the common eswitch mode set checks into a small helper and use it
>from the netlink eswitch set command. This makes the same validation
>available to the devlink core path that applies eswitch mode defaults.
>
>Signed-off-by: Mark Bloch <mbloch@nvidia.com>

Reviewed-by: Jiri Pirko <jiri@nvidia.com>