syzbot


INFO: task hung in nbd_add_socket

Status: auto-closed as invalid on 2021/07/06 19:04
Reported-by: syzbot+19942674ad2a8b4d40bf@syzkaller.appspotmail.com
First crash: 485d, last: 485d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in nbd_add_socket (2) C error 8 21d 107d 0/22 upstream: reported C repro on 2022/03/21 16:06
upstream INFO: task hung in nbd_add_socket 75 150d 229d 0/22 closed as dup on 2021/11/21 13:59
linux-4.14 INFO: task hung in nbd_add_socket (2) C 2 8h12m 193d 0/1 upstream: reported C repro on 2021/12/25 23:00
linux-4.19 INFO: task hung in nbd_add_socket C error 9 23d 485d 0/1 upstream: reported C repro on 2021/03/08 23:07
upstream INFO: task can't die in blk_mq_freeze_queue_wait 221 226d 234d 22/22 fixed on 2022/03/08 16:11

Sample crash report:
INFO: task syz-executor.0:14597 blocked for more than 140 seconds.
      Not tainted 4.14.224-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D29408 14597  13249 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 blk_mq_freeze_queue_wait+0xf8/0x1f0 block/blk-mq.c:154
 nbd_add_socket+0x158/0x7e0 drivers/block/nbd.c:959
 __nbd_ioctl drivers/block/nbd.c:1307 [inline]
 nbd_ioctl+0x394/0xa80 drivers/block/nbd.c:1374
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x540/0x1830 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1893
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x465f69
RSP: 002b:00007fd60bdaa188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465f69
RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003
RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffd50b9322f R14: 00007fd60bdaa300 R15: 0000000000022000
INFO: task syz-executor.0:14610 blocked for more than 140 seconds.
      Not tainted 4.14.224-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D30168 14610  13249 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x540/0x1830 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1893
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x465f69
RSP: 002b:00007fd60bd89188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000465f69
RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003
RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008
R13: 00007ffd50b9322f R14: 00007fd60bd89300 R15: 0000000000022000
INFO: task syz-executor.0:14616 blocked for more than 140 seconds.
      Not tainted 4.14.224-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D29824 14616  13249 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x540/0x1830 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1893
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x465f69
RSP: 002b:00007fd60bd68188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056c0b0 RCX: 0000000000465f69
RDX: 0000000000000006 RSI: 000000000000ab00 RDI: 0000000000000005
RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c0b0
R13: 00007ffd50b9322f R14: 00007fd60bd68300 R15: 0000000000022000
INFO: task syz-executor.0:14622 blocked for more than 140 seconds.
      Not tainted 4.14.224-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D30168 14622  13249 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x540/0x1830 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1893
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x465f69
RSP: 002b:00007fd60bd47188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056c158 RCX: 0000000000465f69
RDX: 0000000000000006 RSI: 000000000000ab00 RDI: 0000000000000005
RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c158
R13: 00007ffd50b9322f R14: 00007fd60bd47300 R15: 0000000000022000
INFO: task syz-executor.0:14630 blocked for more than 140 seconds.
      Not tainted 4.14.224-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D30168 14630  13249 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x540/0x1830 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1893
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x465f69
RSP: 002b:00007fd60bd26188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056c200 RCX: 0000000000465f69
RDX: 0000000000000006 RSI: 000000000000ab00 RDI: 0000000000000003
RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c200
R13: 00007ffd50b9322f R14: 00007fd60bd26300 R15: 0000000000022000
INFO: task syz-executor.0:14635 blocked for more than 140 seconds.
      Not tainted 4.14.224-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D27896 14635  13249 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x540/0x1830 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1893
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x465f69
RSP: 002b:00007fd60bd05188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056c2a8 RCX: 0000000000465f69
RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003
RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c2a8
R13: 00007ffd50b9322f R14: 00007fd60bd05300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1531:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff86ff2967>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
2 locks held by agetty/7915:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff83536f82>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff8352c303>] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156
1 lock held by syz-executor.0/14597:
 #0:  (&nbd->config_lock){+.+.}, at: [<ffffffff838cc21f>] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367
1 lock held by syz-executor.0/14610:
 #0:  (&nbd->config_lock){+.+.}, at: [<ffffffff838cc21f>] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367
1 lock held by syz-executor.0/14616:
 #0:  (&nbd->config_lock){+.+.}, at: [<ffffffff838cc21f>] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367
1 lock held by syz-executor.0/14622:
 #0:  (&nbd->config_lock){+.+.}, at: [<ffffffff838cc21f>] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367
1 lock held by syz-executor.0/14630:
 #0:  (&nbd->config_lock){+.+.}, at: [<ffffffff838cc21f>] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367
1 lock held by syz-executor.0/14635:
 #0:  (&nbd->config_lock){+.+.}, at: [<ffffffff838cc21f>] nbd_ioctl+0x11f/0xa80 drivers/block/nbd.c:1367

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

NMI backtrace for cpu 0
CPU: 0 PID: 1531 Comm: khungtaskd Not tainted 4.14.224-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 14519 Comm: syz-executor.1 Not tainted 4.14.224-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880968e6640 task.stack: ffff88808eb00000
RIP: 0010:__lock_acquire+0x4b1/0x3f20 kernel/locking/lockdep.c:3446
RSP: 0000:ffff88808eb07a10 EFLAGS: 00000006
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 1ffff11012d1cddd RSI: 0000000000000000 RDI: ffff8880968e6eec
RBP: 0000000000000000 R08: 0000000000000001 R09: 00000000000c008d
R10: ffff8880968e6ec8 R11: ffff8880968e6640 R12: ffff8880968e6ee0
R13: 000000000000008d R14: 000000000000008d R15: ffffffff8beb5d40
FS:  00007f1e54bb1700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc12ad50ff CR3: 00000000a5754000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:160
 force_sig_info+0x51/0x410 kernel/signal.c:1243
 force_sig_info_fault.constprop.0+0x185/0x260 arch/x86/mm/fault.c:225
 __bad_area_nosemaphore+0x1d6/0x2c0 arch/x86/mm/fault.c:940
 __bad_area arch/x86/mm/fault.c:974 [inline]
 bad_area_access_error+0x219/0x3e0 arch/x86/mm/fault.c:1013
 __do_page_fault+0x4da/0xad0 arch/x86/mm/fault.c:1422
 page_fault+0x45/0x50 arch/x86/entry/entry_64.S:1123
RIP: 12ad50ff:0x7f1e54bb1300
RSP: 56bf68:000000000056bf60 EFLAGS: 0056bf6c
Code: c5 41 8b 42 20 41 09 e9 8b ac 24 c8 01 00 00 25 ff 1f 00 00 c1 e5 14 41 09 e9 41 09 c1 48 b8 00 00 00 00 00 fc ff df 45 89 4a 20 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2021/03/08 19:03 linux-4.14.y 1d177c0872ab 09fbf400 .config log report info INFO: task hung in nbd_add_socket