This patchset introduces target resume capability to netconsole allowing it to recover targets when underlying low-level interface comes back online.
The patchset starts by refactoring netconsole state representation in order to allow representing deactivated targets (targets that are disabled due to interfaces unregister).
It then modifies netconsole to handle NETDEV_REGISTER events for such targets, setups netpoll and forces the device UP. Targets are matched with incoming interfaces depending on how they were bound in netconsole (by mac or interface name). For these reasons, we also attempt resuming on NETDEV_CHANGENAME.
The patchset includes a selftest that validates netconsole target state transitions and that target is functional after resumed.
Signed-off-by: Andre Carvalho asantostc@gmail.com --- Changes in v10: - Define wrappers around dynamic_netconsole_mutex lock/unlock and use them on process_resume_target to avoid build failures and #ifdefs inside callsite (suggested by Breno). - Refactored other dynamic_netconsole_mutex to use the wrappers for consistency. - Ensure we cancel pending working during removal of dynamic targets, which requires also holding dynamic_netconsole_mutex. - Introduce standalone workqueue to avoid potential leaks during module cleanup, flushing all pending resume events before removing all targets. - Link to v9: https://lore.kernel.org/r/20260104-netcons-retrigger-v9-0-38aa643d2283@gmail...
Changes in v9: - Hold dynamic_netconsole_mutex on process_resume_target. - Cleanup dev_name as part of netconsole_process_cleanups_core to ensure we correctly resume by mac (for targets bound by mac) - Link to v8: https://lore.kernel.org/r/20251128-netcons-retrigger-v8-0-0bccbf4c6385@gmail...
Changes in v8: - Handle NETDEV_REGISTER/CHANGENAME instead of NETDEV_UP (and force the device UP), to increase the chances of succesfully resuming a target. This requires using a workqueue instead of inline in the event notifier as we can't UP the device otherwise. - Link to v7: https://lore.kernel.org/r/20251126-netcons-retrigger-v7-0-1d86dba83b1c@gmail...
Changes in v7: - selftest: use ${EXIT_STATUS} instead of ${ksft_pass} to avoid shellcheck warning - Link to v6: https://lore.kernel.org/r/20251121-netcons-retrigger-v6-0-9c03f5a2bd6f@gmail...
Changes in v6: - Rebase on top of net-next to resolve conflicts, no functional changes. - Link to v5: https://lore.kernel.org/r/20251119-netcons-retrigger-v5-0-2c7dda6055d6@gmail...
Changes in v5: - patch 3: Set (de)enslaved target as DISABLED instead of DEACTIVATED to prevent resuming it. - selftest: Fix test cleanup by moving trap line to outside of loop and remove unneeded 'local' keyword - Rename maybe_resume_target to resume_target, add netconsole_ prefix to process_resumable_targets. - Hold device reference before calling __netpoll_setup. - Link to v4: https://lore.kernel.org/r/20251116-netcons-retrigger-v4-0-5290b5f140c2@gmail...
Changes in v4: - Simplify selftest cleanup, removing trap setup in loop. - Drop netpoll helper (__setup_netpoll_hold) and manage reference inside netconsole. - Move resume_list processing logic to separate function. - Link to v3: https://lore.kernel.org/r/20251109-netcons-retrigger-v3-0-1654c280bbe6@gmail...
Changes in v3: - Resume by mac or interface name depending on how target was created. - Attempt to resume target without holding target list lock, by moving the target to a temporary list. This is required as netpoll may attempt to allocate memory. - Link to v2: https://lore.kernel.org/r/20250921-netcons-retrigger-v2-0-a0e84006237f@gmail...
Changes in v2: - Attempt to resume target in the same thread, instead of using workqueue . - Add wrapper around __netpoll_setup (patch 4). - Renamed resume_target to maybe_resume_target and moved conditionals to inside its implementation, keeping code more clear. - Verify that device addr matches target mac address when target was setup using mac. - Update selftest to cover targets bound by mac and interface name. - Fix typo in selftest comment and sort tests alphabetically in Makefile. - Link to v1: https://lore.kernel.org/r/20250909-netcons-retrigger-v1-0-3aea904926cf@gmail...
--- Andre Carvalho (5): netconsole: convert 'enabled' flag to enum for clearer state management netconsole: clear dev_name for devices bound by mac netconsole: introduce helpers for dynamic_netconsole_mutex lock/unlock netconsole: resume previously deactivated target selftests: netconsole: validate target resume
Breno Leitao (2): netconsole: add target_state enum netconsole: add STATE_DEACTIVATED to track targets disabled by low level
drivers/net/netconsole.c | 305 ++++++++++++++++----- tools/testing/selftests/drivers/net/Makefile | 1 + .../selftests/drivers/net/lib/sh/lib_netcons.sh | 35 ++- .../selftests/drivers/net/netcons_resume.sh | 97 +++++++ 4 files changed, 364 insertions(+), 74 deletions(-) --- base-commit: 60d8484c4cec811f5ceb6550655df74490d1a165 change-id: 20250816-netcons-retrigger-a4f547bfc867
Best regards,