| Message ID | 1336591268.12504.62.camel@edumazet-glaptop |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
Eric Dumazet <eric.dumazet@gmail.com> writes: > From: Eric Dumazet <edumazet@google.com> > > commit 7d3d43dab4e9 (net: In unregister_netdevice_notifier unregister > the netdevices.) makes pktgen crashing at module unload. Awesome an anceint race was flushed out. > [ 296.820578] BUG: spinlock bad magic on CPU#6, rmmod/3267 > [ 296.820719] lock: ffff880310c38000, .magic: ffff8803, .owner: <none>/-1, .owner_cpu: -1 > [ 296.820943] Pid: 3267, comm: rmmod Not tainted 3.4.0-rc5+ #254 > [ 296.821079] Call Trace: > [ 296.821211] [<ffffffff8168a715>] spin_dump+0x8a/0x8f > [ 296.821345] [<ffffffff8168a73b>] spin_bug+0x21/0x26 > [ 296.821507] [<ffffffff812b4741>] do_raw_spin_lock+0x131/0x140 > [ 296.821648] [<ffffffff8169188e>] _raw_spin_lock+0x1e/0x20 > [ 296.821786] [<ffffffffa00cc0fd>] __pktgen_NN_threads+0x4d/0x140 [pktgen] > [ 296.821928] [<ffffffffa00ccf8d>] pktgen_device_event+0x10d/0x1e0 [pktgen] > [ 296.822073] [<ffffffff8154ed4f>] unregister_netdevice_notifier+0x7f/0x100 > [ 296.822216] [<ffffffffa00d2a0b>] pg_cleanup+0x48/0x73 [pktgen] > [ 296.822357] [<ffffffff8109528e>] sys_delete_module+0x17e/0x2a0 > [ 296.822502] [<ffffffff81699652>] system_call_fastpath+0x16/0x1b > > Fix this by deleting objects from pktgen_threads list before their > freeing. That seems reasonable. Would it be easier to call unregister_netdevice_notifer before shutting down the threads, so you don't have the weird cases to deal with during shutdown? It looks like pg_cleanup doesn't take the pktgen_thread_lock, so I suspect that there are still races. Eric > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: Eric W. Biederman <ebiederm@xmission.com> > --- > net/core/pktgen.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/net/core/pktgen.c b/net/core/pktgen.c > index ffb5d38..f632abf 100644 > --- a/net/core/pktgen.c > +++ b/net/core/pktgen.c > @@ -3762,6 +3762,7 @@ static void __exit pg_cleanup(void) > list_for_each_safe(q, n, &pktgen_threads) { > t = list_entry(q, struct pktgen_thread, th_list); > kthread_stop(t->tsk); > + list_del(&t->th_list); > kfree(t); > } > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/core/pktgen.c b/net/core/pktgen.c index ffb5d38..f632abf 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -3762,6 +3762,7 @@ static void __exit pg_cleanup(void) list_for_each_safe(q, n, &pktgen_threads) { t = list_entry(q, struct pktgen_thread, th_list); kthread_stop(t->tsk); + list_del(&t->th_list); kfree(t); }