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INFO: task hung in do_exit

Status: upstream: reported on 2024/07/12 05:24
Reported-by: syzbot+e52c8252d99d8bc06837@syzkaller.appspotmail.com
First crash: 57d, last: 57d
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in do_exit syz done error 125 952d 1974d 0/27 closed as invalid on 2022/02/08 10:54
linux-4.14 INFO: task hung in do_exit syz inconclusive 8 948d 1962d 0/1 upstream: reported syz repro on 2019/04/25 02:28
android-414 INFO: task hung in do_exit syz 19 1742d 1974d 0/1 public: reported syz repro on 2019/04/13 00:01
linux-4.19 INFO: task hung in do_exit C error 58 580d 1968d 0/1 upstream: reported C repro on 2019/04/19 20:32
upstream INFO: task can't die in show_free_areas serial C error 152 4d05h 957d 0/27 upstream: reported C repro on 2022/01/24 13:23
android-49 INFO: task hung in do_exit syz 18 1789d 1973d 0/3 public: reported syz repro on 2019/04/14 09:28

Sample crash report:
INFO: task syz.1.2716:14214 blocked for more than 143 seconds.
      Not tainted 6.1.98-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.2716      state:D stack:25528 pid:14214 ppid:11846  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 coredump_task_exit kernel/exit.c:432 [inline]
 do_exit+0x555/0x26a0 kernel/exit.c:821
 do_group_exit+0x202/0x2b0 kernel/exit.c:1021
 get_signal+0x16f7/0x17d0 kernel/signal.c:2862
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc178775bd9
RSP: 002b:00007ffc459933d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffdfc RBX: 00000000000d8381 RCX: 00007fc178775bd9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc178904044
RBP: 00000000000d834f R08: 0000000000000010 R09: 0000001a459936ff
R10: 00007ffc459934c0 R11: 0000000000000246 R12: 00007fc178904044
R13: 0000000000000032 R14: 00007ffc459934e0 R15: 00007ffc459934c0
 </TASK>
INFO: task syz.1.2716:14219 blocked for more than 145 seconds.
      Not tainted 6.1.98-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.2716      state:D stack:25752 pid:14219 ppid:11846  flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0xac/0x300 kernel/time/timer.c:1941
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common+0x3e1/0x6c0 kernel/sched/completion.c:106
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion_state+0x18/0x30 kernel/sched/completion.c:254
 coredump_wait fs/coredump.c:405 [inline]
 do_coredump+0x9c5/0x2700 fs/coredump.c:562
 get_signal+0x1454/0x17d0 kernel/signal.c:2848
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc178639f60
RSP: 002b:00007fc1794adb38 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000000 RBX: 00007fc178904040 RCX: 00007fc178775bd9
RDX: 00007fc1794adb40 RSI: 00007fc1794adc70 RDI: 000000000000000b
RBP: 00007fc178904038 R08: 0000000000000010 R09: 00007fc1794ae6c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc178904044
R13: 000000000000006e R14: 00007ffc45993210 R15: 00007ffc459932f8
 </TASK>
INFO: task syz.0.2763:14366 blocked for more than 145 seconds.
      Not tainted 6.1.98-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2763      state:D stack:25752 pid:14366 ppid:10130  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 coredump_task_exit kernel/exit.c:432 [inline]
 do_exit+0x555/0x26a0 kernel/exit.c:821
 do_group_exit+0x202/0x2b0 kernel/exit.c:1021
 get_signal+0x16f7/0x17d0 kernel/signal.c:2862
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9b89775bd9
RSP: 002b:00007ffd5bf0c9e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffdfc RBX: 00000000000dc199 RCX: 00007f9b89775bd9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f9b89904044
RBP: 00000000000dc167 R08: 0000000000000010 R09: 000000195bf0cd0f
R10: 00007ffd5bf0cad0 R11: 0000000000000246 R12: 00007f9b89904044
R13: 0000000000000032 R14: 00007ffd5bf0caf0 R15: 00007ffd5bf0cad0
 </TASK>
INFO: task syz.0.2763:14373 blocked for more than 145 seconds.
      Not tainted 6.1.98-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2763      state:D stack:25832 pid:14373 ppid:10130  flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0xac/0x300 kernel/time/timer.c:1941
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common+0x3e1/0x6c0 kernel/sched/completion.c:106
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion_state+0x18/0x30 kernel/sched/completion.c:254
 coredump_wait fs/coredump.c:405 [inline]
 do_coredump+0x9c5/0x2700 fs/coredump.c:562
 get_signal+0x1454/0x17d0 kernel/signal.c:2848
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9b89639f60
RSP: 002b:00007f9b8a4c1ab8 EFLAGS: 00000246 ORIG_RAX: 000000000000000a
RAX: 0000000000000000 RBX: 00007f9b89904038 RCX: 00007f9b89775bd9
RDX: 00007f9b8a4c1ac0 RSI: 00007f9b8a4c1bf0 RDI: 000000000000000b
RBP: 00007f9b897e4e60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f9b89904038 R15: 00007ffd5bf0c908
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d12aed0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d12b6d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by khungtaskd/27:
 #0: ffffffff8d12ad00 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8d12ad00 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8d12ad00 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494
2 locks held by getty/3308:
 #0: ffff888028905098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198
4 locks held by kworker/u4:17/7298:
 #0: ffff8880b993aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
 #1: ffff8880b9927788 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x43d/0x770 kernel/sched/psi.c:1000
 #2: ffff8880782b0d40 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1114 [inline]
 #2: ffff8880782b0d40 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0xa0/0x1480 net/mac80211/ibss.c:1680
 #3: ffffffff8d12ad00 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #3: ffffffff8d12ad00 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #3: ffffffff8d12ad00 (rcu_read_lock){....}-{1:2}, at: ieee80211_sta_active_ibss+0xb1/0x310 net/mac80211/ibss.c:654

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 6.1.98-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf88/0xfd0 kernel/hung_task.c:377
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 2984 Comm: syslogd Not tainted 6.1.98-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:49 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline]
RIP: 0010:unwind_next_frame+0x4c8/0x2220 arch/x86/kernel/unwind_orc.c:448
Code: 0f b6 04 08 84 c0 75 27 48 63 03 48 01 d8 48 8d 4b 04 4c 39 e8 4c 0f 46 f9 48 8d 43 fc 48 0f 47 e8 4c 0f 46 e3 49 39 ef 76 a9 <e9> a7 fd ff ff 89 d9 80 e1 07 80 c1 03 38 c1 7c cd 48 89 df 48 89
RSP: 0018:ffffc900001e0200 EFLAGS: 00000212
RAX: ffffffff8edf5528 RBX: ffffffff8edf552c RCX: ffffffff8edf5530
RDX: ffffffff8f788e20 RSI: ffffffff8a12e9b1 RDI: dffffc0000000000
RBP: ffffffff8edf552c R08: 0000000000000003 R09: ffffc900001e03d0
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8edf552c
R13: ffffffff8a12e9b0 R14: ffffffff8edf5524 R15: ffffffff8edf5530
FS:  00007fac286f3380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb9402d03f8 CR3: 000000007e9a9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:955 [inline]
 __kmalloc_node_track_caller+0xb1/0x220 mm/slab_common.c:975
 kmalloc_reserve net/core/skbuff.c:446 [inline]
 __alloc_skb+0x135/0x670 net/core/skbuff.c:515
 __netdev_alloc_skb+0xfb/0x500 net/core/skbuff.c:579
 netdev_alloc_skb include/linux/skbuff.h:3206 [inline]
 dev_alloc_skb include/linux/skbuff.h:3219 [inline]
 __ieee80211_beacon_get+0xc7d/0x2110 net/mac80211/tx.c:5258
 ieee80211_beacon_get_tim+0xb1/0x5d0 net/mac80211/tx.c:5340
 ieee80211_beacon_get include/net/mac80211.h:5248 [inline]
 mac80211_hwsim_beacon_tx+0x1d2/0xaa0 drivers/net/wireless/mac80211_hwsim.c:2086
 __iterate_interfaces+0x21e/0x4b0 net/mac80211/util.c:788
 ieee80211_iterate_active_interfaces_atomic+0xd4/0x170 net/mac80211/util.c:824
 mac80211_hwsim_beacon+0xd0/0x1e0 drivers/net/wireless/mac80211_hwsim.c:2142
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_run_softirq+0x196/0x2c0 kernel/time/hrtimer.c:1767
 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
 __do_softirq kernel/softirq.c:605 [inline]
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:654
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:666
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:check_region_inline mm/kasan/generic.c:175 [inline]
RIP: 0010:kasan_check_range+0x1d/0x290 mm/kasan/generic.c:189
Code: c3 cc cc cc cc cc cc cc cc cc cc cc cc 55 41 57 41 56 53 b0 01 48 85 f6 0f 84 9a 01 00 00 48 89 fd 48 01 f5 0f 82 5a 02 00 00 <48> 89 fd 48 c1 ed 2f 81 fd ff ff 01 00 0f 82 47 02 00 00 48 89 fb
RSP: 0018:ffffc9000315f418 EFLAGS: 00000286
RAX: 0000000000000001 RBX: 0000000000000010 RCX: ffffffff813cb207
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc9000315f590
RBP: ffffc9000315f5a0 R08: 000000000000000c R09: ffffc9000315f630
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc9000315f540
R13: ffffffff8ef89c24 R14: 0000000000000000 R15: ffffc9000315f590
 memset+0x1f/0x40 mm/kasan/shadow.c:44
 unwind_next_frame+0xde7/0x2220 arch/x86/kernel/unwind_orc.c:546
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x292/0x510 mm/slub.c:3683
 __unix_dgram_recvmsg+0xcb3/0x1260 net/unix/af_unix.c:2530
 sock_recvmsg_nosec net/socket.c:1022 [inline]
 sock_recvmsg net/socket.c:1040 [inline]
 sock_read_iter+0x3b2/0x4b0 net/socket.c:1121
 call_read_iter include/linux/fs.h:2259 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x88d/0xbf0 fs/read_write.c:470
 ksys_read+0x19c/0x2c0 fs/read_write.c:613
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fac28847b6a
Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffd40eb8418 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fac28847b6a
RDX: 00000000000000ff RSI: 00005577cc77b950 RDI: 0000000000000000
RBP: 00005577cc77b910 R08: 0000000000000001 R09: 0000000000000000
R10: 00007fac289e63a3 R11: 0000000000000246 R12: 00005577cc77b996
R13: 00005577cc77b950 R14: 0000000000000000 R15: 00007fac28a24a80
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/12 05:24 linux-6.1.y 266ee8e06d5b eaeb5c15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in do_exit
* Struck through repros no longer work on HEAD.