quoted

Since the bonding tests can't run on real HW it can't live directly in
tools/testing/selftests/drivers/net/ we need to move it to either the
netdevsim group or the bonding group.  

Are you talking abouttools/testing/selftests/drivers/net/bonding as the
bonding group?

With the changed above, this is how the selftest looks like now:

Author: Breno Leitao [off-list ref]
Date:   Wed Sep 17 01:46:26 2025 -0700

    selftest: netcons: add test for netconsole over bonded interfaces
    
    This patch adds a selftest that verifies netconsole functionality
    over bonded network interfaces using netdevsim. It sets up two bonded
    interfaces acting as transmit (TX) and receive (RX) ends, placed in
    separate network namespaces. The test sends kernel log messages and
    verifies that they are properly received on the bonded RX interfaces
    with both IPv4 and IPv6, and using basic and extended netconsole
    formats.
    
    This patchset aims to test a long-standing netpoll are where netpoll has
    multiple users. (in this case netconsole and bonding). A similar
    selftest has been discussed in [1] and [2].
    
    This test also try to enable bonding and netpoll at the same time, and
    make sure that it fails.
    
    Link: https://lore.kernel.org/all/20250905-netconsole_torture-v3-0-875c7febd316@debian.org/ (local) [1]
    Link: https://lore.kernel.org/lkml/96b940137a50e5c387687bb4f57de8b0435a653f.1404857349.git.decot@googlers.com/ (local) [2]
    Signed-off-by: Breno Leitao [off-list ref]

diff --git a/tools/testing/selftests/drivers/net/bonding/Makefile b/tools/testing/selftests/drivers/net/bonding/Makefile
index 3462783ed3aca..d7fb239c02814 100644
--- a/tools/testing/selftests/drivers/net/bonding/Makefile
+++ b/tools/testing/selftests/drivers/net/bonding/Makefile

@@ -8,6 +8,7 @@ TEST_PROGS := \
 	dev_addr_lists.sh \
 	mode-1-recovery-updelay.sh \
 	mode-2-recovery-updelay.sh \
+	netcons_over_bonding.sh \
 	bond_options.sh \
 	bond-eth-type-change.sh \
 	bond_macvlan_ipvlan.sh \

diff --git a/tools/testing/selftests/drivers/net/bonding/config b/tools/testing/selftests/drivers/net/bonding/config
index 4d16a69ffc650..c9e609ff5b5dd 100644
--- a/tools/testing/selftests/drivers/net/bonding/config
+++ b/tools/testing/selftests/drivers/net/bonding/config

@@ -10,3 +10,8 @@ CONFIG_NET_CLS_MATCHALL=m
 CONFIG_NET_SCH_INGRESS=y
 CONFIG_NLMON=y
 CONFIG_VETH=y
+CONFIG_NETDEVSIM=m
+CONFIG_CONFIGFS_FS=y
+CONFIG_NETCONSOLE=m
+CONFIG_NETCONSOLE_DYNAMIC=y
+CONFIG_NETCONSOLE_EXTENDED_LOG=y

+cleanup_bond
+trap - EXIT
+exit "${EXIT_STATUS}"

diff --git a/tools/testing/selftests/drivers/net/lib/sh/lib_netcons.sh b/tools/testing/selftests/drivers/net/lib/sh/lib_netcons.sh
index 9b5ef8074440c..4862d025b7c74 100644
--- a/tools/testing/selftests/drivers/net/lib/sh/lib_netcons.sh
+++ b/tools/testing/selftests/drivers/net/lib/sh/lib_netcons.sh

@@ -28,17 +28,24 @@ NETCONS_PATH="${NETCONS_CONFIGFS}"/"${TARGET}"
 # NAMESPACE will be populated by setup_ns with a random value
 NAMESPACE=""
 
-# IDs for netdevsim
+# IDs for netdevsim. We either use NSIM_DEV_{1,2}_ID for standard test
+# or NSIM_BOND_{T,R}X_{1,2} for the bonding tests. Not both at the
+# same time.
 NSIM_DEV_1_ID=$((256 + RANDOM % 256))
 NSIM_DEV_2_ID=$((512 + RANDOM % 256))
+NSIM_BOND_TX_1=$((768 + RANDOM % 256))
+NSIM_BOND_TX_2=$((1024 + RANDOM % 256))
+NSIM_BOND_RX_1=$((1280 + RANDOM % 256))
+NSIM_BOND_RX_2=$((1536 + RANDOM % 256))
 NSIM_DEV_SYS_NEW="/sys/bus/netdevsim/new_device"
+NSIM_DEV_SYS_LINK="/sys/bus/netdevsim/link_device"
+NSIM_DEV_SYS_DEL="/sys/bus/netdevsim/del_device"
 
 # Used to create and delete namespaces
 source "${LIBDIR}"/../../../../net/lib.sh
 
 # Create netdevsim interfaces
 create_ifaces() {
-
 	echo "$NSIM_DEV_2_ID" > "$NSIM_DEV_SYS_NEW"
 	echo "$NSIM_DEV_1_ID" > "$NSIM_DEV_SYS_NEW"
 	udevadm settle 2> /dev/null || true

@@ -54,7 +61,6 @@ create_ifaces() {
 }
 
 link_ifaces() {
-	local NSIM_DEV_SYS_LINK="/sys/bus/netdevsim/link_device"
 	local SRCIF_IFIDX=$(cat /sys/class/net/"$SRCIF"/ifindex)
 	local DSTIF_IFIDX=$(cat /sys/class/net/"$DSTIF"/ifindex)
 

@@ -96,6 +102,33 @@ function select_ipv4_or_ipv6()
 	fi
 }
 
+# Create 4 netdevsim interfaces. Two of them will be bound to TX bonding iface
+# and the other two will be bond to the RX interface (on the other namespace)
+function create_ifaces_bond() {
+	echo "$NSIM_BOND_TX_1" > "$NSIM_DEV_SYS_NEW"
+	echo "$NSIM_BOND_TX_2" > "$NSIM_DEV_SYS_NEW"
+	echo "$NSIM_BOND_RX_1" > "$NSIM_DEV_SYS_NEW"
+	echo "$NSIM_BOND_RX_2" > "$NSIM_DEV_SYS_NEW"
+	udevadm settle 2> /dev/null || true
+
+	local BOND_TX1=/sys/bus/netdevsim/devices/netdevsim"$NSIM_BOND_TX_1"
+	local BOND_TX2=/sys/bus/netdevsim/devices/netdevsim"$NSIM_BOND_TX_2"
+	local BOND_RX1=/sys/bus/netdevsim/devices/netdevsim"$NSIM_BOND_RX_1"
+	local BOND_RX2=/sys/bus/netdevsim/devices/netdevsim"$NSIM_BOND_RX_2"
+
+	# TX
+	BOND_TX1_IF=$(find "$BOND_TX1"/net -maxdepth 1 -type d ! \
+		-path "$BOND_TX1"/net -exec basename {} \; | grep -v net)
+	BOND_TX2_IF=$(find "$BOND_TX2"/net -maxdepth 1 -type d ! \
+		-path "$BOND_TX2"/net -exec basename {} \; | grep -v net)
+
+	# RX
+	BOND_RX1_IF=$(find "$BOND_RX1"/net -maxdepth 1 -type d ! \
+		-path "$BOND_RX1"/net -exec basename {} \; | grep -v net)
+	BOND_RX2_IF=$(find "$BOND_RX2"/net -maxdepth 1 -type d ! \
+		-path "$BOND_RX2"/net -exec basename {} \; | grep -v net)
+}
+
 function set_network() {
 	local IP_VERSION=${1:-"ipv4"}
 

@@ -180,8 +213,6 @@ function disable_release_append() {
 }
 
 function do_cleanup() {
-	local NSIM_DEV_SYS_DEL="/sys/bus/netdevsim/del_device"
-
 	# Delete netdevsim devices
 	echo "$NSIM_DEV_2_ID" > "$NSIM_DEV_SYS_DEL"
 	echo "$NSIM_DEV_1_ID" > "$NSIM_DEV_SYS_DEL"

@@ -193,14 +224,26 @@ function do_cleanup() {
 	echo "${DEFAULT_PRINTK_VALUES}" > /proc/sys/kernel/printk
 }
 
-function cleanup() {
+function cleanup_netcons() {
 	# delete netconsole dynamic reconfiguration
-	echo 0 > "${NETCONS_PATH}"/enabled
+	# do not fail if the target is already disabled
+	if [[ ! -d "${NETCONS_PATH}" ]]
+	then
+		# in some cases this is called before netcons path is created
+		return
+	fi
+	if [[ $(cat "${NETCONS_PATH}"/enabled) != 0 ]]
+	then
+		echo 0 > "${NETCONS_PATH}"/enabled || true
+	fi
 	# Remove all the keys that got created during the selftest
 	find "${NETCONS_PATH}/userdata/" -mindepth 1 -type d -delete
 	# Remove the configfs entry
 	rmdir "${NETCONS_PATH}"
+}
 
+function cleanup() {
+	cleanup_netcons
 	do_cleanup
 }
 

@@ -377,3 +420,105 @@ function wait_for_port() {
 	# more frequently on IPv6
 	sleep 1
 }
+
+# netdevsim link BOND_TX to BOND_RX interfaces
+function link_ifaces_bond() {
+	local BOND_TX1_IFIDX
+	local BOND_TX2_IFIDX
+	local BOND_RX1_IFIDX
+	local BOND_RX2_IFIDX
+
+	BOND_TX1_IFIDX=$(cat /sys/class/net/"$BOND_TX1_IF"/ifindex)
+	BOND_TX2_IFIDX=$(cat /sys/class/net/"$BOND_TX2_IF"/ifindex)
+	BOND_RX1_IFIDX=$(cat /sys/class/net/"$BOND_RX1_IF"/ifindex)
+	BOND_RX2_IFIDX=$(cat /sys/class/net/"$BOND_RX2_IF"/ifindex)
+
+	exec {NAMESPACE_FD}</var/run/netns/"${NAMESPACE}"
+	exec {INITNS_FD}</proc/self/ns/net
+
+	# Bind the dst interfaces to namespace
+	ip link set "${BOND_RX1_IF}" netns "${NAMESPACE}"
+	ip link set "${BOND_RX2_IF}" netns "${NAMESPACE}"
+
+	# Linking TX ifaces to the RX ones (on the other namespace}
+	echo "${INITNS_FD}:$BOND_TX1_IFIDX $NAMESPACE_FD:$BOND_RX1_IFIDX"  \
+		> "$NSIM_DEV_SYS_LINK"
+	echo "${INITNS_FD}:$BOND_TX2_IFIDX $NAMESPACE_FD:$BOND_RX2_IFIDX"  \
+		> "$NSIM_DEV_SYS_LINK"
+}
+
+# Create "bond_tx_XX" and "bond_rx_XX" interfaces, and set DSTIF and SRCIF with
+# the bonding interfaces
+function setup_bonding_ifaces() {
+	local RAND=$(( RANDOM % 100 ))
+	BONDTX_IF="bond_tx_$RAND"
+	BONDRX_IF="bond_rx_$RAND"
+
+	if ! ip link add "${BONDTX_IF}" type bond mode balance-rr
+	then
+		echo "Failed to create bond TX interface. Is CONFIG_BONDING set?" >&2
+		# only clean nsim ifaces and namespace. Nothing else has been
+		# initialized
+		cleanup_bond_nsim
+		trap - EXIT
+		exit "${ksft_skip}"
+	fi
+	ip link set "${BOND_TX1_IF}" down
+	ip link set "${BOND_TX2_IF}" down
+
+	ip link set "${BOND_TX1_IF}" master "${BONDTX_IF}"
+	ip link set "${BOND_TX2_IF}" master "${BONDTX_IF}"
+	ip link set "${BONDTX_IF}" up
+
+	# now create the RX bonding iface
+	ip netns exec "${NAMESPACE}" \
+		ip link add "${BONDRX_IF}" type bond mode balance-rr
+	ip netns exec "${NAMESPACE}" \
+		ip link set "${BOND_RX1_IF}" down
+	ip netns exec "${NAMESPACE}" \
+		ip link set "${BOND_RX2_IF}" down
+
+	ip netns exec "${NAMESPACE}" \
+		ip link set "${BOND_RX1_IF}" master "${BONDRX_IF}"
+	ip netns exec "${NAMESPACE}" \
+		ip link set "${BOND_RX2_IF}" master "${BONDRX_IF}"
+	ip netns exec "${NAMESPACE}" \
+		ip link set "${BONDRX_IF}" up
+	ip netns exec "${NAMESPACE}" \
+		ip link set "${BOND_RX1_IF}" up
+	ip netns exec "${NAMESPACE}" \
+		ip link set "${BOND_RX2_IF}" up
+
+}
+
+# Clean up netdevsim ifaces created for bonding test
+function cleanup_bond_nsim() {
+	echo "$NSIM_BOND_TX_1" > "$NSIM_DEV_SYS_DEL"
+	echo "$NSIM_BOND_TX_2" > "$NSIM_DEV_SYS_DEL"
+	echo "$NSIM_BOND_RX_1" > "$NSIM_DEV_SYS_DEL"
+	echo "$NSIM_BOND_RX_2" > "$NSIM_DEV_SYS_DEL"
+	cleanup_all_ns
+}
+
+# cleanup tests that use bonding interfaces
+function cleanup_bond() {
+	cleanup_netcons
+
+	# Delete TX ifaces
+	ip link set "${BONDTX_IF}" down  2> /dev/null|| true
+	ip link set "${BOND_TX1_IF}" down || true
+	ip link set "${BOND_TX2_IF}" down || true
+	ip link delete "${BONDTX_IF}" type bond  2> /dev/null || true
+
+	# Delete RX ifaces
+	ip netns exec "${NAMESPACE}" \
+		ip link set "${BONDRX_IF}" down || true
+	ip netns exec "${NAMESPACE}" \
+		ip link set "${BOND_RX1_IF}" down || true
+	ip netns exec "${NAMESPACE}" \
+		ip link set "${BOND_RX2_IF}" down || true
+	ip netns exec "${NAMESPACE}" \
+		ip link delete "${BONDRX_IF}" type bond  || true
+
+	cleanup_bond_nsim
+}