kernel/Documentation/networking/netconsole.rst, branch linux-rolling-stable

Documentation: netconsole: Separate literal code blocks for full and short netcat command name versions

2025-10-31T23:54:22Z

Both full and short (abbreviated) command name versions of netcat example are combined in single literal code block due to 'or::' paragraph being indented one more space than the preceding paragraph (before the short version example). Unindent it to separate the versions. Signed-off-by: Bagas Sanjaya Reviewed-by: Randy Dunlap Tested-by: Randy Dunlap Link: https://patch.msgid.link/20251030075013.40418-1-bagasdotme@gmail.com Signed-off-by: Jakub Kicinski

Documentation: netconsole: Remove obsolete contact people

2025-10-30T00:40:19Z

Breno Leitao has been listed in MAINTAINERS as netconsole maintainer since 7c938e438c56db ("MAINTAINERS: make Breno the netconsole maintainer"), but the documentation says otherwise that bug reports should be sent to original netconsole authors. Remove obsolate contact info. Signed-off-by: Bagas Sanjaya Reviewed-by: Randy Dunlap Tested-by: Randy Dunlap Link: https://patch.msgid.link/20251028132027.48102-1-bagasdotme@gmail.com Signed-off-by: Jakub Kicinski

docs: netconsole: document msgid feature

2025-06-18T09:46:10Z

Add documentation explaining the msgid feature in netconsole. This feature appends unique id to the userdata dictionary. The message ID is populated from a per-target 32 bit counter which is incremented for each message sent to the target. This allows a target to detect if messages are dropped before reaching the target. Signed-off-by: Gustavo Luiz Duarte Signed-off-by: David S. Miller

docs: netconsole: document release feature

2025-03-21T17:59:25Z

Add documentation explaining the kernel release auto-population feature in netconsole. This feature appends kernel version information to the userdata dictionary in every message sent when enabled via the `release_enabled` file in the configfs hierarchy. Signed-off-by: Breno Leitao Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250314-netcons_release-v1-6-07979c4b86af@debian.org Signed-off-by: Paolo Abeni

netconsole: allow selection of egress interface via MAC address

2025-03-19T18:17:58Z

Currently, netconsole has two methods of configuration - module parameter and configfs. The former interface allows for netconsole activation earlier during boot (by specifying the module parameter on the kernel command line), so it is preferred for debugging issues which arise before userspace is up/the configfs interface can be used. The module parameter syntax requires specifying the egress interface name. This requirement makes it hard to use for a couple reasons: - The egress interface name can be hard or impossible to predict. For example, installing a new network card in a system can change the interface names assigned by the kernel. - When constructing the module parameter, one may have trouble determining the original (kernel-assigned) name of the interface (which is the name that should be given to netconsole) if some stable interface naming scheme is in effect. A human can usually look at kernel logs to determine the original name, but this is very painful if automation is constructing the parameter. For these reasons, allow selection of the egress interface via MAC address when configuring netconsole using the module parameter. Update the netconsole documentation with an example of the new syntax. Selection of egress interface by MAC address via configfs is far less interesting (since when this interface can be used, one should be able to easily convert between MAC address and interface name), so it is left unimplemented. Signed-off-by: Uday Shankar Reviewed-by: Breno Leitao Tested-by: Breno Leitao Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250312-netconsole-v6-2-3437933e79b8@purestorage.com Signed-off-by: Paolo Abeni

netconsole: docs: document the task name feature

2025-03-04T14:28:28Z

Add documentation for the netconsole task name feature in Documentation/networking/netconsole.rst. This explains how to enable task name via configfs and demonstrates the output format. The documentation includes: - How to enable/disable the feature via taskname_enabled - The format of the task name in the output - An example showing the task name appearing in messages Signed-off-by: Breno Leitao Reviewed-by: Simon Horman Signed-off-by: Paolo Abeni

netconsole: docs: Add documentation for CPU number auto-population

2025-02-10T15:04:18Z

Update the netconsole documentation to explain the new feature that allows automatic population of the CPU number. The key changes include introducing a new section titled "CPU number auto population in userdata", explaining how to enable the CPU number auto-population feature by writing to the "populate_cpu_nr" file in the netconsole configfs hierarchy. This documentation update ensures users are aware of the new CPU number auto-population functionality and how to leverage it for better demultiplexing and visibility of parallel netconsole output. Signed-off-by: Breno Leitao Reviewed-by: Simon Horman Signed-off-by: David S. Miller

netcons: Add udp send fail statistics to netconsole

2024-12-05T03:16:59Z

Enhance observability of netconsole. Packet sends can fail. Start tracking at least two failure possibilities: ENOMEM and NET_XMIT_DROP for every target. Stats are exposed via an additional attribute in CONFIGFS. The exposed statistics allows easier debugging of cases when netconsole messages were not seen by receivers, eliminating the guesswork if the sender thinks that messages in question were sent out. Stats are not reset on enable/disable/change remote ip/etc, they belong to the netcons target itself. Reported-by: Breno Leitao Closes: https://lore.kernel.org/all/ZsWoUzyK5du9Ffl+@gmail.com/ Signed-off-by: Maksym Kutsevol Link: https://patch.msgid.link/20241202-netcons-add-udp-send-fail-statistics-to-netconsole-v5-2-70e82239f922@kutsevol.com Signed-off-by: Jakub Kicinski

net: netconsole: Add continuation line prefix to userdata messages

2024-03-11T21:07:57Z

Add a space (' ') prefix to every userdata line to match docs for dev-kmsg. To account for this extra character in each userdata entry, reduce userdata entry names (directory name) from 54 characters to 53. According to the dev-kmsg docs, a space is used for subsequent lines to mark them as continuation lines. > A line starting with ' ', is a continuation line, adding > key/value pairs to the log message, which provide the machine > readable context of the message, for reliable processing in > userspace. Testing for this patch:: cd /sys/kernel/config/netconsole && mkdir cmdline0 cd cmdline0 mkdir userdata/test && echo "hello" > userdata/test/value mkdir userdata/test2 && echo "hello2" > userdata/test2/value echo "message" > /dev/kmsg Outputs:: 6.8.0-rc5-virtme,12,493,231373579,-;message test=hello test2=hello2 And I confirmed all testing works as expected from the original patchset Fixes: df03f830d099 ("net: netconsole: cache userdata formatted string in netconsole_target") Signed-off-by: Matthew Wood Reviewed-by: Breno Leitao Link: https://lore.kernel.org/r/20240308002525.248672-1-thepacketgeek@gmail.com Signed-off-by: Jakub Kicinski

net: netconsole: add docs for appending netconsole user data

2024-02-09T10:23:45Z

Add a new User Data section to the netconsole docs to describe the appending of user data capability (for netconsole dynamic configuration) with usage and netconsole output examples. Co-developed-by: Breno Leitao Signed-off-by: Breno Leitao Signed-off-by: Matthew Wood Signed-off-by: David S. Miller