BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 40s!

[syzbot]

Hello,

syzkaller hit the following crash on
e8b684315214053f29f7f78643aefd19da342976
git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.


CC: []

TCP: request_sock_TCP: Possible SYN flooding on port 20028. Sending
cookies. Check SNMP counters.
BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 40s!
Showing busy workqueues and worker pools:
workqueue events: flags=0x0
pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256
in-flight: 800:key_garbage_collector
pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=2/256
pending: e1000_watchdog, vmstat_shepherd
workqueue mm_percpu_wq: flags=0x8
pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=2/256
pending: lru_add_drain_per_cpu BAR(5819), vmstat_update
pool 2: cpus=1 node=0 flags=0x0 nice=0 hung=40s workers=4 idle: 1263 3928 18


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[Dmitry Vyukov]

This bug title was superseded by "BUG: workqueue lockup" title

#syz invalid

On Fri, Sep 1, 2017 at 9:59 PM, syzbot
<bot+097de6f841e96a51ee...@syzkaller.appspotmail.com>
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