syzbot


INFO: task hung in __lru_add_drain_all

Status: auto-obsoleted due to no activity on 2023/08/21 02:18
Reported-by: syzbot+e320fc3ead7e827d8f25@syzkaller.appspotmail.com
First crash: 449d, last: 449d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in __lru_add_drain_all 1 58d 58d 0/3 upstream: reported on 2024/05/17 20:43
upstream INFO: task hung in __lru_add_drain_all (2) mm 192 now 58d 0/27 upstream: reported on 2024/05/17 22:28
upstream INFO: task hung in __lru_add_drain_all net C done error 71 245d 1046d 0/27 auto-obsoleted due to no activity on 2024/02/20 10:46

Sample crash report:
INFO: task khugepaged:32 blocked for more than 147 seconds.
      Not tainted 5.15.108-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:khugepaged      state:D stack:26016 pid:   32 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_timeout+0xac/0x300 kernel/time/timer.c:1860
 do_wait_for_common+0x2d9/0x480 kernel/sched/completion.c:85
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
 __flush_work+0x124/0x1a0 kernel/workqueue.c:3090
 __lru_add_drain_all+0x8eb/0x9e0 mm/swap.c:833
 khugepaged_do_scan mm/khugepaged.c:2259 [inline]
 khugepaged+0x16a/0x1330 mm/khugepaged.c:2320
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
INFO: task kworker/u4:4:1133 blocked for more than 147 seconds.
      Not tainted 5.15.108-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:4    state:D stack:24088 pid: 1133 ppid:     2 flags:0x00004000
Workqueue: events_unbound fsnotify_connector_destroy_workfn
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_timeout+0xac/0x300 kernel/time/timer.c:1860
 do_wait_for_common+0x2d9/0x480 kernel/sched/completion.c:85
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
 __synchronize_srcu+0x2b9/0x360 kernel/rcu/srcutree.c:930
 fsnotify_connector_destroy_workfn+0x40/0xa0 fs/notify/mark.c:164
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2306
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
INFO: task kworker/u4:11:3924 blocked for more than 147 seconds.
      Not tainted 5.15.108-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:11   state:D stack:24088 pid: 3924 ppid:     2 flags:0x00004000
Workqueue: events_unbound fsnotify_mark_destroy_workfn
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_timeout+0xac/0x300 kernel/time/timer.c:1860
 do_wait_for_common+0x2d9/0x480 kernel/sched/completion.c:85
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
 __synchronize_srcu+0x2b9/0x360 kernel/rcu/srcutree.c:930
 fsnotify_mark_destroy_workfn+0x142/0x340 fs/notify/mark.c:861
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2306
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/0:1/13:
1 lock held by khungtaskd/26:
 #0: ffffffff8c91b920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by khugepaged/32:
 #0: ffffffff8c9b1828 (lock#4){+.+.}-{3:3}, at: __lru_add_drain_all+0x67/0x9e0 mm/swap.c:782
2 locks held by kworker/u4:4/1133:
 #0: ffff888011c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279
 #1: ffffc9000581fd20 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281
2 locks held by getty/3269:
 #0: ffff88802469b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900020a32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1da0 drivers/tty/n_tty.c:2147
3 locks held by syz-executor.3/3632:
3 locks held by syz-executor.4/3634:
2 locks held by kworker/u4:11/3924:
 #0: ffff888011c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279
 #1: ffffc90005277d20 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281
2 locks held by kworker/u4:12/3926:
2 locks held by dhcpcd/10173:
 #0: ffff88807e836120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1649 [inline]
 #0: ffff88807e836120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2a/0xc90 net/packet/af_packet.c:3159
 #1: ffffffff8c91fe68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #1: ffffffff8c91fe68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:840
2 locks held by dhcpcd/10175:
 #0: ffff88802c950120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1649 [inline]
 #0: ffff88802c950120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2a/0xc90 net/packet/af_packet.c:3159
 #1: ffffffff8c91fe68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
 #1: ffffffff8c91fe68 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:840
1 lock held by dhcpcd/10203:
 #0: ffff8880769c6120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1649 [inline]
 #0: ffff8880769c6120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2a/0xc90 net/packet/af_packet.c:3159
1 lock held by dhcpcd/10204:
 #0: ffff888031b06120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1649 [inline]
 #0: ffff888031b06120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2a/0xc90 net/packet/af_packet.c:3159
1 lock held by dhcpcd/10211:
 #0: ffff88802d7d2120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1649 [inline]
 #0: ffff88802d7d2120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2a/0xc90 net/packet/af_packet.c:3159
1 lock held by dhcpcd/10402:
 #0: ffff888077fd6120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1649 [inline]
 #0: ffff888077fd6120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x2a/0xc90 net/packet/af_packet.c:3159
1 lock held by syz-executor.1/11101:
1 lock held by syz-executor.0/11103:

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

NMI backtrace for cpu 0
CPU: 0 PID: 26 Comm: khungtaskd Not tainted 5.15.108-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 11111 Comm: syz-executor.0 Not tainted 5.15.108-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
RIP: 0010:__unix_dgram_recvmsg+0xb2d/0x1260 net/unix/af_unix.c:2389
Code: db 0f 89 98 02 00 00 e8 01 28 91 f8 4c 8b 7c 24 40 49 8d 5d 38 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 48 89 df e8 79 7f da f8 48 8b 1b 48 85 db 0f 84 bb 00 00 00
RSP: 0018:ffffc90010467740 EFLAGS: 00000246
RAX: 1ffff1100e4692f7 RBX: ffff8880723497b8 RCX: dffffc0000000000
RDX: ffffc90003ae1000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc900104678f0 R08: ffffffff88ee9322 R09: ffffed100368110d
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff888072349780 R14: 0000000000000002 R15: 1ffff9200208cefc
FS:  00007f1a0a462700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002018d030 CR3: 000000003173f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ____sys_recvmsg+0x286/0x530
 ___sys_recvmsg+0x1ec/0x690 net/socket.c:2673
 do_recvmmsg+0x36f/0x8f0 net/socket.c:2767
 __sys_recvmmsg net/socket.c:2846 [inline]
 __do_sys_recvmmsg net/socket.c:2869 [inline]
 __se_sys_recvmmsg net/socket.c:2862 [inline]
 __x64_sys_recvmmsg+0x195/0x240 net/socket.c:2862
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f1a0bf11169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1a0a462168 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f1a0c031050 RCX: 00007f1a0bf11169
RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 00007f1a0bf6cca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe476d05df R14: 00007f1a0a462300 R15: 0000000000022000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/23 02:18 linux-5.15.y 3299fb36854f 2b32bd34 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in __lru_add_drain_all
* Struck through repros no longer work on HEAD.