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| author | Daniel Borkmann <daniel@iogearbox.net> | 2022-05-25 00:56:18 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-05-25 22:00:48 -0700 |
| commit | ed6cd6a17896561b9f51ab4c0d9bbb29e762b597 (patch) | |
| tree | 48d0d7fa93663bc51c4295279a2ccfd34dd14768 /net/core/neighbour.c | |
| parent | b3b1a17538d3ef6a9667b2271216fd16d7678ab5 (diff) | |
| download | lwn-ed6cd6a17896561b9f51ab4c0d9bbb29e762b597.tar.gz lwn-ed6cd6a17896561b9f51ab4c0d9bbb29e762b597.zip | |
net, neigh: Set lower cap for neigh_managed_work rearming
Yuwei reported that plain reuse of DELAY_PROBE_TIME to rearm work queue
in neigh_managed_work is problematic if user explicitly configures the
DELAY_PROBE_TIME to 0 for a neighbor table. Such misconfig can then hog
CPU to 100% processing the system work queue. Instead, set lower interval
bound to HZ which is totally sufficient. Yuwei is additionally looking
into making the interval separately configurable from DELAY_PROBE_TIME.
Reported-by: Yuwei Wang <wangyuweihx@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/netdev/797c3c53-ce1b-9f60-e253-cda615788f4a@iogearbox.net
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/3b8c5aa906c52c3a8c995d1b2e8ccf650ea7c716.1653432794.git.daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/core/neighbour.c')
| -rw-r--r-- | net/core/neighbour.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 47b6c1f0fdbb..54625287ee5b 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -1579,7 +1579,7 @@ static void neigh_managed_work(struct work_struct *work) list_for_each_entry(neigh, &tbl->managed_list, managed_list) neigh_event_send_probe(neigh, NULL, false); queue_delayed_work(system_power_efficient_wq, &tbl->managed_work, - NEIGH_VAR(&tbl->parms, DELAY_PROBE_TIME)); + max(NEIGH_VAR(&tbl->parms, DELAY_PROBE_TIME), HZ)); write_unlock_bh(&tbl->lock); } |