* [PATCH net-next v2 1/2] selftest: netcons: refactor target creation
2025-09-04 18:00 [PATCH net-next v2 0/2] net: selftest: Introduce netconsole torture test Breno Leitao
@ 2025-09-04 18:00 ` Breno Leitao
2025-09-04 18:00 ` [PATCH net-next v2 2/2] selftest: netcons: create a torture test Breno Leitao
2025-09-04 21:59 ` [PATCH net-next v2 0/2] net: selftest: Introduce netconsole " Jakub Kicinski
2 siblings, 0 replies; 6+ messages in thread
From: Breno Leitao @ 2025-09-04 18:00 UTC (permalink / raw)
To: Andrew Lunn, David S. Miller, Eric Dumazet, Jakub Kicinski,
Paolo Abeni, Shuah Khan
Cc: linux-kernel, netdev, linux-kselftest, asantostc, efault, calvin,
kernel-team, Breno Leitao
Extract the netconsole target creation from create_dynamic_target(), by
moving it from create_dynamic_target() into a new helper function. This
enables other tests to use the creation of netconsole targets with
arbitrary parameters and no sleep.
The new helper will be utilized by forthcoming torture-type selftests
that require dynamic target management.
Signed-off-by: Breno Leitao <leitao@debian.org>
---
.../selftests/drivers/net/lib/sh/lib_netcons.sh | 30 ++++++++++++++--------
1 file changed, 19 insertions(+), 11 deletions(-)
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 8e1085e896472..9b5ef8074440c 100644
--- a/tools/testing/selftests/drivers/net/lib/sh/lib_netcons.sh
+++ b/tools/testing/selftests/drivers/net/lib/sh/lib_netcons.sh
@@ -113,31 +113,39 @@ function set_network() {
configure_ip
}
-function create_dynamic_target() {
- local FORMAT=${1:-"extended"}
+function _create_dynamic_target() {
+ local FORMAT="${1:?FORMAT parameter required}"
+ local NCPATH="${2:?NCPATH parameter required}"
DSTMAC=$(ip netns exec "${NAMESPACE}" \
ip link show "${DSTIF}" | awk '/ether/ {print $2}')
# Create a dynamic target
- mkdir "${NETCONS_PATH}"
+ mkdir "${NCPATH}"
- echo "${DSTIP}" > "${NETCONS_PATH}"/remote_ip
- echo "${SRCIP}" > "${NETCONS_PATH}"/local_ip
- echo "${DSTMAC}" > "${NETCONS_PATH}"/remote_mac
- echo "${SRCIF}" > "${NETCONS_PATH}"/dev_name
+ echo "${DSTIP}" > "${NCPATH}"/remote_ip
+ echo "${SRCIP}" > "${NCPATH}"/local_ip
+ echo "${DSTMAC}" > "${NCPATH}"/remote_mac
+ echo "${SRCIF}" > "${NCPATH}"/dev_name
if [ "${FORMAT}" == "basic" ]
then
# Basic target does not support release
- echo 0 > "${NETCONS_PATH}"/release
- echo 0 > "${NETCONS_PATH}"/extended
+ echo 0 > "${NCPATH}"/release
+ echo 0 > "${NCPATH}"/extended
elif [ "${FORMAT}" == "extended" ]
then
- echo 1 > "${NETCONS_PATH}"/extended
+ echo 1 > "${NCPATH}"/extended
fi
- echo 1 > "${NETCONS_PATH}"/enabled
+ echo 1 > "${NCPATH}"/enabled
+
+}
+
+function create_dynamic_target() {
+ local FORMAT=${1:-"extended"}
+ local NCPATH=${2:-"$NETCONS_PATH"}
+ _create_dynamic_target "${FORMAT}" "${NCPATH}"
# This will make sure that the kernel was able to
# load the netconsole driver configuration. The console message
--
2.47.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH net-next v2 2/2] selftest: netcons: create a torture test
2025-09-04 18:00 [PATCH net-next v2 0/2] net: selftest: Introduce netconsole torture test Breno Leitao
2025-09-04 18:00 ` [PATCH net-next v2 1/2] selftest: netcons: refactor target creation Breno Leitao
@ 2025-09-04 18:00 ` Breno Leitao
2025-09-05 11:27 ` Andre Carvalho
2025-09-04 21:59 ` [PATCH net-next v2 0/2] net: selftest: Introduce netconsole " Jakub Kicinski
2 siblings, 1 reply; 6+ messages in thread
From: Breno Leitao @ 2025-09-04 18:00 UTC (permalink / raw)
To: Andrew Lunn, David S. Miller, Eric Dumazet, Jakub Kicinski,
Paolo Abeni, Shuah Khan
Cc: linux-kernel, netdev, linux-kselftest, asantostc, efault, calvin,
kernel-team, Breno Leitao
Create a netconsole test that puts a lot of pressure on the netconsole
list manipulation. Do it by creating dynamic targets and deleting
targets while messages are being sent. Also put interface down while the
messages are being sent, as creating parallel targets.
The code launches three background jobs on distinct schedules:
* Toggle netcons target every 30 iterations
* create and delete random_target every 50 iterations
* toggle iface every 70 iterations
This creates multiple concurrency sources that interact with netconsole
states. This is good practice to simulate stress, and exercise netpoll
and netconsole locks.
This test already found an issue as reported in [1]
Link: https://lore.kernel.org/all/20250901-netpoll_memleak-v1-1-34a181977dfc@debian.org/ [1]
Signed-off-by: Breno Leitao <leitao@debian.org>
---
tools/testing/selftests/drivers/net/Makefile | 1 +
.../selftests/drivers/net/netcons_torture.sh | 127 +++++++++++++++++++++
2 files changed, 128 insertions(+)
diff --git a/tools/testing/selftests/drivers/net/Makefile b/tools/testing/selftests/drivers/net/Makefile
index 984ece05f7f92..2b253b1ff4f38 100644
--- a/tools/testing/selftests/drivers/net/Makefile
+++ b/tools/testing/selftests/drivers/net/Makefile
@@ -17,6 +17,7 @@ TEST_PROGS := \
netcons_fragmented_msg.sh \
netcons_overflow.sh \
netcons_sysdata.sh \
+ netcons_torture.sh \
netpoll_basic.py \
ping.py \
queues.py \
diff --git a/tools/testing/selftests/drivers/net/netcons_torture.sh b/tools/testing/selftests/drivers/net/netcons_torture.sh
new file mode 100755
index 0000000000000..ed95cdac7f47a
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/netcons_torture.sh
@@ -0,0 +1,127 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: GPL-2.0
+
+# Repeatedly send kernel messages, toggles netconsole targets on and off,
+# creates and deletes targets in parallel, and toggles the source interface to
+# simulate stress conditions.
+#
+# This test aims verify the robustness of netconsole under dynamic
+# configurations and concurrent operations.
+#
+# The major goal is to run this test with LOCKDEP, Kmemleak and KASAN to make
+# sure no issues is reported.
+#
+# Author: Breno Leitao <leitao@debian.org>
+
+set -euo pipefail
+
+SCRIPTDIR=$(dirname "$(readlink -e "${BASH_SOURCE[0]}")")
+
+source "${SCRIPTDIR}"/lib/sh/lib_netcons.sh
+
+# Number of times the main loop run
+ITERATIONS=${1:-1000}
+
+# Only test extended format
+FORMAT="extended"
+# And ipv6 only
+IP_VERSION="ipv6"
+
+# Create, enable and delete some targets.
+create_and_delete_random_target() {
+ COUNT=2
+ RND_PREFIX=$(mktemp -u netcons_rnd_XXXX_)
+
+ if [ -d "${NETCONS_CONFIGFS}/${RND_PREFIX}${COUNT}" ] || \
+ [ -d "${NETCONS_CONFIGFS}/${RND_PREFIX}0" ]; then
+ echo "Function didn't finish yet, skipping it." >&2
+ return
+ fi
+
+ # enable COUNT targets
+ for i in $(seq ${COUNT})
+ do
+ RND_TARGET="${RND_PREFIX}"${i}
+ RND_TARGET_PATH="${NETCONS_CONFIGFS}"/"${RND_TARGET}"
+
+ # Basic population so the target can come up
+ _create_dynamic_target "${FORMAT}" "${RND_TARGET_PATH}"
+ done
+
+ echo "netconsole selftest: ${COUNT} additional target was created" > /dev/kmsg
+ # disable them all
+ for i in $(seq ${COUNT})
+ do
+ RND_TARGET="${RND_PREFIX}"${i}
+ RND_TARGET_PATH="${NETCONS_CONFIGFS}"/"${RND_TARGET}"
+ echo 0 > "${RND_TARGET_PATH}"/enabled
+ rmdir "${RND_TARGET_PATH}"
+ done
+}
+
+# Disable and enable the target mid-air, while messages
+# are being transmitted.
+toggle_netcons_target() {
+ for i in $(seq 2)
+ do
+ if [ ! -d "${NETCONS_PATH}" ]
+ then
+ break
+ fi
+ echo 0 > "${NETCONS_PATH}"/enabled 2> /dev/null || true
+ # Try to enable a bit harder, given it might fail to enable
+ # Write to `enabled` might fail depending on the lock, which is
+ # highly contentious here
+ for _ in $(seq 5)
+ do
+ echo 1 > "${NETCONS_PATH}"/enabled 2> /dev/null || true
+ done
+ done
+}
+
+toggle_iface(){
+ ip link set "${SRCIF}" down
+ ip link set "${SRCIF}" up
+}
+
+# Start here
+
+modprobe netdevsim 2> /dev/null || true
+modprobe netconsole 2> /dev/null || true
+
+# Check for basic system dependency and exit if not found
+check_for_dependencies
+# Set current loglevel to KERN_INFO(6), and default to KERN_NOTICE(5)
+echo "6 5" > /proc/sys/kernel/printk
+# Remove the namespace, interfaces and netconsole target on exit
+trap cleanup EXIT
+# Create one namespace and two interfaces
+set_network "${IP_VERSION}"
+# Create a dynamic target for netconsole
+create_dynamic_target "${FORMAT}"
+
+for i in $(seq "$ITERATIONS")
+do
+ for _ in $(seq 10)
+ do
+ echo "${MSG}: ${TARGET} ${i}" > /dev/kmsg
+ done
+ wait
+
+ if (( i % 30 == 0 )); then
+ toggle_netcons_target &
+ fi
+
+ if (( i % 50 == 0 )); then
+ # create some targets, enable them, send msg and disable
+ # all in a parallel thread
+ create_and_delete_random_target &
+ fi
+
+ if (( i % 70 == 0 )); then
+ toggle_iface &
+ fi
+done
+wait
+
+exit "${ksft_pass}"
--
2.47.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH net-next v2 2/2] selftest: netcons: create a torture test
2025-09-04 18:00 ` [PATCH net-next v2 2/2] selftest: netcons: create a torture test Breno Leitao
@ 2025-09-05 11:27 ` Andre Carvalho
0 siblings, 0 replies; 6+ messages in thread
From: Andre Carvalho @ 2025-09-05 11:27 UTC (permalink / raw)
To: Breno Leitao
Cc: Andrew Lunn, David S. Miller, Eric Dumazet, Jakub Kicinski,
Paolo Abeni, Shuah Khan, linux-kernel, netdev, linux-kselftest,
efault, calvin, kernel-team
On Thu, Sep 04, 2025 at 11:00:41AM -0700, Breno Leitao wrote:
> +# This test aims verify the robustness of netconsole under dynamic
> +# configurations and concurrent operations.
Just a small nit: "aims to verify" or simply "verifies".
Reviewed-by: Andre Carvalho <asantostc@gmail.com>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH net-next v2 0/2] net: selftest: Introduce netconsole torture test
2025-09-04 18:00 [PATCH net-next v2 0/2] net: selftest: Introduce netconsole torture test Breno Leitao
2025-09-04 18:00 ` [PATCH net-next v2 1/2] selftest: netcons: refactor target creation Breno Leitao
2025-09-04 18:00 ` [PATCH net-next v2 2/2] selftest: netcons: create a torture test Breno Leitao
@ 2025-09-04 21:59 ` Jakub Kicinski
2025-09-05 17:27 ` Breno Leitao
2 siblings, 1 reply; 6+ messages in thread
From: Jakub Kicinski @ 2025-09-04 21:59 UTC (permalink / raw)
To: Breno Leitao
Cc: Andrew Lunn, David S. Miller, Eric Dumazet, Paolo Abeni,
Shuah Khan, linux-kernel, netdev, linux-kselftest, asantostc,
efault, calvin, kernel-team
On Thu, 04 Sep 2025 11:00:39 -0700 Breno Leitao wrote:
> Create a netconsole test that puts a lot of pressure on the netconsole
> list manipulation. Do it by creating dynamic targets and deleting
> targets while messages are being sent. Also put interface down while the
>
> In order to do it, refactor create_dynamic_target(), so it can be used to
> create random targets in the torture test.
You either have to post it in the same series as the fix, or wait for
the fix to be present in net-next. Without your pending fix this will
obviously not pass thru the CI :/
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH net-next v2 0/2] net: selftest: Introduce netconsole torture test
2025-09-04 21:59 ` [PATCH net-next v2 0/2] net: selftest: Introduce netconsole " Jakub Kicinski
@ 2025-09-05 17:27 ` Breno Leitao
0 siblings, 0 replies; 6+ messages in thread
From: Breno Leitao @ 2025-09-05 17:27 UTC (permalink / raw)
To: Jakub Kicinski
Cc: Andrew Lunn, David S. Miller, Eric Dumazet, Paolo Abeni,
Shuah Khan, linux-kernel, netdev, linux-kselftest, asantostc,
efault, calvin, kernel-team
On Thu, Sep 04, 2025 at 02:59:25PM -0700, Jakub Kicinski wrote:
> On Thu, 04 Sep 2025 11:00:39 -0700 Breno Leitao wrote:
> > Create a netconsole test that puts a lot of pressure on the netconsole
> > list manipulation. Do it by creating dynamic targets and deleting
> > targets while messages are being sent. Also put interface down while the
> >
> > In order to do it, refactor create_dynamic_target(), so it can be used to
> > create random targets in the torture test.
>
> You either have to post it in the same series as the fix, or wait for
> the fix to be present in net-next. Without your pending fix this will
> obviously not pass thru the CI :/
Ack! I've sent the netpoll fix and the selftest in the same patchset, as
you suggested.
https://lore.kernel.org/all/20250905-netconsole_torture-v3-0-875c7febd316@debian.org/
--breno
^ permalink raw reply [flat|nested] 6+ messages in thread