mirror of
https://github.com/torvalds/linux.git
synced 2026-01-12 00:42:35 +08:00
b3fc08ab9a
The following order of calls currently deadlocks if:
- device has threaded=1; and
- NAPI has persistent config with threaded=0.
netif_napi_add_weight_config()
dev->threaded == 1
napi_kthread_create()
napi_enable()
napi_restore_config()
napi_set_threaded(0)
napi_stop_kthread()
while (NAPIF_STATE_SCHED)
msleep(20)
We deadlock because disabled NAPI has STATE_SCHED set.
Creating a thread in netif_napi_add() just to destroy it in
napi_disable() is fairly ugly in the first place. Let's read
both the device config and the NAPI config in netif_napi_add().
Fixes: e6d7626881 ("net: Update threaded state in napi config in netif_set_threaded")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20250809001205.1147153-4-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>