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INFO: task hung in ip6gre_exit_batch_net

Status: auto-closed as invalid on 2020/02/29 06:17
Reported-by: syzbot+152cf29490da97f01995@syzkaller.appspotmail.com
First crash: 1637d, last: 1637d
▶ ▼ Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in ip6gre_exit_batch_net (6) net 1 286d 286d 0/26 closed as invalid on 2023/09/07 14:36
upstream INFO: task hung in ip6gre_exit_batch_net (2) net 3 1619d 1620d 0/26 auto-closed as invalid on 2020/01/17 16:16
linux-4.19 INFO: task hung in ip6gre_exit_batch_net (2) 1 1234d 1234d 0/1 auto-closed as invalid on 2021/04/06 21:09
linux-4.19 INFO: task hung in ip6gre_exit_batch_net (3) 7 833d 1000d 0/1 auto-closed as invalid on 2022/05/13 06:16
upstream INFO: task hung in ip6gre_exit_batch_net (4) net syz unreliable 44 887d 938d 0/26 closed as invalid on 2021/12/14 20:12
upstream INFO: task hung in ip6gre_exit_batch_net net 6 1658d 2151d 0/26 closed as dup on 2018/06/04 15:23
upstream INFO: task hung in ip6gre_exit_batch_net (5) net 1 665d 665d 0/26 auto-closed as invalid on 2022/09/28 06:40
upstream INFO: task hung in ip6gre_exit_batch_net (3) net 18 1122d 1437d 0/26 auto-closed as invalid on 2021/06/27 10:57

Sample crash report:
INFO: task kworker/u4:0:7 blocked for more than 140 seconds.
      Not tainted 4.19.81 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:0    D25776     7      2 0x80000000
Workqueue: netns cleanup_net
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x866/0x1dc0 kernel/sched/core.c:3515
 schedule+0x92/0x1c0 kernel/sched/core.c:3559
 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1782
 do_wait_for_common kernel/sched/completion.c:83 [inline]
 __wait_for_common kernel/sched/completion.c:104 [inline]
 wait_for_common kernel/sched/completion.c:115 [inline]
 wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136
 __flush_work+0x49f/0x870 kernel/workqueue.c:2920
 flush_work+0x18/0x20 kernel/workqueue.c:2941
 flush_all_backlogs net/core/dev.c:5290 [inline]
 rollback_registered_many+0x516/0xda0 net/core/dev.c:7990
 unregister_netdevice_many.part.0+0x1b/0x1f0 net/core/dev.c:9115
 unregister_netdevice_many+0x3b/0x50 net/core/dev.c:9114
 ip6gre_exit_batch_net+0x535/0x750 net/ipv6/ip6_gre.c:1624
 ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:156
 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:552
 process_one_work+0x989/0x1750 kernel/workqueue.c:2153
 worker_thread+0x98/0xe40 kernel/workqueue.c:2296
 kthread+0x354/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Showing all locks held in the system:
5 locks held by kworker/u4:0/7:
 #0: 000000000920722d ((wq_completion)"%s""netns"){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 000000000920722d ((wq_completion)"%s""netns"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 000000000920722d ((wq_completion)"%s""netns"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 000000000920722d ((wq_completion)"%s""netns"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 000000000920722d ((wq_completion)"%s""netns"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 000000000920722d ((wq_completion)"%s""netns"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 000000000920722d ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124
 #1: 000000000a8641ca (net_cleanup_work){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128
 #2: 00000000c7d15728 (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0x960 net/core/net_namespace.c:519
 #3: 0000000041969763 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
 #4: 0000000002d8e3b0 (cpu_hotplug_lock.rw_sem){++++}, at: get_online_cpus include/linux/cpu.h:132 [inline]
 #4: 0000000002d8e3b0 (cpu_hotplug_lock.rw_sem){++++}, at: flush_all_backlogs net/core/dev.c:5283 [inline]
 #4: 0000000002d8e3b0 (cpu_hotplug_lock.rw_sem){++++}, at: rollback_registered_many+0x3df/0xda0 net/core/dev.c:7990
1 lock held by khungtaskd/1040:
 #0: 0000000006db2598 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438
1 lock held by khugepaged/1047:
3 locks held by rs:main Q:Reg/7390:
 #0: 00000000ea3d056d (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767
 #1: 0000000074ec7448 (sb_writers#4){.+.+}, at: file_start_write include/linux/fs.h:2775 [inline]
 #1: 0000000074ec7448 (sb_writers#4){.+.+}, at: vfs_write+0x429/0x560 fs/read_write.c:548
 #2: 0000000006db2598 (rcu_read_lock){....}, at: fast_dput fs/dcache.c:714 [inline]
 #2: 0000000006db2598 (rcu_read_lock){....}, at: dput+0x38/0x670 fs/dcache.c:833
1 lock held by rsyslogd/7393:
 #0: 000000006d78088b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767
2 locks held by getty/7514:
 #0: 000000008432878d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 00000000ca44a10f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7515:
 #0: 00000000c6422278 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 0000000014f56332 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7516:
 #0: 0000000045162537 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 00000000ca569f56 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7517:
 #0: 00000000d135b8a3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 00000000359eb0bd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7518:
 #0: 00000000286d2338 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 00000000e876d8eb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7519:
 #0: 0000000059829531 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 000000001bfae958 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7520:
 #0: 0000000037977674 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 00000000685f46ca (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by kworker/0:4/7590:
 #0: 00000000759a4fd7 ((wq_completion)"events"){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 00000000759a4fd7 ((wq_completion)"events"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 00000000759a4fd7 ((wq_completion)"events"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 00000000759a4fd7 ((wq_completion)"events"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 00000000759a4fd7 ((wq_completion)"events"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 00000000759a4fd7 ((wq_completion)"events"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 00000000759a4fd7 ((wq_completion)"events"){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124
 #1: 000000001ad6305c (key_gc_work){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128
1 lock held by syz-executor.1/24966:

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1040 Comm: khungtaskd Not tainted 4.19.81 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x9df/0xee0 kernel/hung_task.c:287
 kthread+0x354/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 24966 Comm: syz-executor.1 Not tainted 4.19.81 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:loop1+0x1fd/0x892
Code: 41 21 df 01 d0 44 21 d6 c5 ed 73 d2 11 45 31 f5 45 31 c7 c5 ed ef d3 c4 43 7b f0 f1 16 45 01 ef c5 25 ef da 45 31 e6 44 01 f8 <c4> 43 7b f0 e1 02 c4 42 25 00 dc c5 a5 fe e0 45 31 e6 45 89 cc 45
RSP: 0018:ffff88808a4871c0 EFLAGS: 00000297
RAX: 00000000e102fbc0 RBX: 00000000218a1eac RCX: 000000005c2ca548
RDX: 0000000009801e05 RSI: 000000005609b458 RDI: 0000000000000080
RBP: ffff88808a487468 R08: 0000000050957075 R09: 0000000043d89578
R10: 00000000562bb45e R11: 00000000b45d3ca0 R12: 00000000abc21ec4
R13: 00000000a00d4f29 R14: 00000000c997ffcb R15: 00000000f02ab382
FS:  00007eff0b5b6700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000021000000 CR3: 000000009709b000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 sha256_avx2_update+0x2d/0x40 arch/x86/crypto/sha256_ssse3_glue.c:235
 crypto_shash_update+0xf2/0x2b0 crypto/shash.c:126
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:373 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:393 [inline]
 ima_calc_file_hash+0x553/0x970 security/integrity/ima/ima_crypto.c:458
 ima_collect_measurement+0x50f/0x5c0 security/integrity/ima/ima_api.c:231
 process_measurement+0xeca/0x1560 security/integrity/ima/ima_main.c:284
 ima_file_check+0xc5/0x110 security/integrity/ima/ima_main.c:391
 do_last fs/namei.c:3422 [inline]
 path_openat+0x1130/0x45e0 fs/namei.c:3534
 do_filp_open+0x1a1/0x280 fs/namei.c:3564
 do_sys_open+0x3fe/0x550 fs/open.c:1088
 __do_sys_open fs/open.c:1106 [inline]
 __se_sys_open fs/open.c:1101 [inline]
 __x64_sys_open+0x7e/0xc0 fs/open.c:1101
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459f49
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007eff0b5b5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f49
RDX: 0000000000000000 RSI: 0000000000141042 RDI: 0000000020000100
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007eff0b5b66d4
R13: 00000000004fa77f R14: 00000000004dc190 R15: 00000000ffffffff

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/01 06:16 linux-4.19.y ef244c308885 a41ca8fa .config console log report ci2-linux-4-19
* Struck through repros no longer work on HEAD.