syzbot


INFO: task hung in get_super

Status: auto-obsoleted due to no activity on 2023/05/20 18:34
Subsystems: fs arm
[Documentation on labels]
First crash: 643d, last: 459d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in get_super 1 205d 205d 0/3 auto-obsoleted due to no activity on 2024/02/08 07:44
upstream INFO: task hung in get_super (2) reiserfs 1 260d 260d 0/26 auto-obsoleted due to no activity on 2023/12/05 22:55
android-49 INFO: task hung in get_super 4 2166d 2194d 0/3 auto-closed as invalid on 2019/02/22 14:56

Sample crash report:
INFO: task syz-executor.2:17580 blocked for more than 143 seconds.
      Not tainted 6.0.0-rc5-syzkaller-00089-g6879c2d3b960 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:28456 pid:17580 ppid:  8727 flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5182 [inline]
 __schedule+0xadf/0x52b0 kernel/sched/core.c:6494
 schedule+0xda/0x1b0 kernel/sched/core.c:6570
 rwsem_down_read_slowpath+0x59f/0xb10 kernel/locking/rwsem.c:1087
 __down_read_common kernel/locking/rwsem.c:1252 [inline]
 __down_read kernel/locking/rwsem.c:1261 [inline]
 down_read+0xe2/0x450 kernel/locking/rwsem.c:1501
 get_super+0x12c/0x250 fs/super.c:794
 fsync_bdev+0x14/0xc0 block/bdev.c:215
 blkdev_flushbuf block/ioctl.c:352 [inline]
 blkdev_common_ioctl+0x10d0/0x1a30 block/ioctl.c:477
 blkdev_ioctl+0x2be/0x800 block/ioctl.c:608
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4811c89409
RSP: 002b:00007f4812daa168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4811d9bf80 RCX: 00007f4811c89409
RDX: 0000000000000000 RSI: 0000000000001261 RDI: 0000000000000003
RBP: 00007f4811ce4367 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe05588f1f R14: 00007f4812daa300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8bf888b0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8bf885b0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507
1 lock held by khungtaskd/28:
 #0: ffffffff8bf89400 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6492
2 locks held by kworker/u4:4/57:
2 locks held by getty/3285:
 #0: ffff88814b3a8098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc90002d262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef0/0x13e0 drivers/tty/n_tty.c:2177
4 locks held by kworker/0:16/4079:
 #0: ffff8880b9a39f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:544
 #1: ffff8880b9a277c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x3e7/0x4e0 kernel/sched/psi.c:885
 #2: ffff8880b9a283d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x5a/0x1f0 kernel/time/timer.c:999
 #3: ffffffff91435e20 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x12e/0x3e0 lib/debugobjects.c:658
1 lock held by syz-executor.2/8670:
1 lock held by syz-executor.5/8965:
1 lock held by syz-executor.1/13862:
1 lock held by syz-executor.4/13962:
1 lock held by syz-executor.3/13970:
1 lock held by syz-executor.0/14046:
1 lock held by syz-executor.2/17580:
 #0: ffff88807bde60e0 (&type->s_umount_key#58){++++}-{3:3}, at: get_super+0x12c/0x250 fs/super.c:794
1 lock held by syz-executor.2/17653:
 #0: ffff88807bde60e0 (&type->s_umount_key#58){++++}-{3:3}, at: get_super+0x12c/0x250 fs/super.c:794
1 lock held by syz-executor.2/17697:
 #0: ffff88807bde60e0 (&type->s_umount_key#58){++++}-{3:3}, at: get_super+0x12c/0x250 fs/super.c:794

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.0.0-rc5-syzkaller-00089-g6879c2d3b960 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x46/0x14f lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x206/0x250 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xc18/0xf50 kernel/hung_task.c:369
 kthread+0x2e4/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 1076 Comm: kworker/u4:5 Not tainted 6.0.0-rc5-syzkaller-00089-g6879c2d3b960 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__kasan_check_read+0x4/0x10 mm/kasan/shadow.c:31
Code: 0f 0b 48 83 c4 60 5b 5d 41 5c c3 48 05 00 80 00 00 48 89 fb 48 39 c7 0f 82 a2 ec 74 07 eb e1 cc cc cc cc cc cc cc 48 8b 0c 24 <89> f6 31 d2 e9 b3 fa ff ff 0f 1f 00 48 8b 0c 24 89 f6 ba 01 00 00
RSP: 0018:ffffc900044f7a28 EFLAGS: 00000057
RAX: 0000000000000000 RBX: 0000000000000027 RCX: ffffffff815f1f53
RDX: 1ffff11003f59c6d RSI: 0000000000000008 RDI: ffffffff908e4940
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff908e4a27
R10: fffffbfff211c944 R11: 0000000000000000 R12: ffff88801face348
R13: ffff88801facd880 R14: ffff88801face2f8 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0239238f0 CR3: 00000000262f8000 CR4: 0000000000350ee0
Call Trace:
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 hlock_class kernel/locking/lockdep.c:227 [inline]
 __lock_acquire+0xbc3/0x56d0 kernel/locking/lockdep.c:5050
 lock_acquire kernel/locking/lockdep.c:5666 [inline]
 lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631
 rcu_lock_acquire include/linux/rcupdate.h:280 [inline]
 rcu_read_lock include/linux/rcupdate.h:706 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0x12d/0xfa0 net/batman-adv/network-coding.c:719
 process_one_work+0x991/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e4/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/09/17 04:09 upstream 6879c2d3b960 dd9a85ff .config console log report info [disk image] [vmlinux] ci-upstream-kasan-gce-root INFO: task hung in get_super
2022/08/30 11:45 upstream dcf8e5633e2e 5b44472d .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in get_super
2022/12/22 03:05 linux-next e45fb347b630 4067838e .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: task hung in get_super
2023/02/19 18:34 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 2d3827b3f393 bcdf85f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in get_super
2022/09/01 20:41 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 85413d1e802e 86c46e46 .config console log report info ci-upstream-gce-arm64 INFO: task hung in get_super
2022/08/19 20:52 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 680fb5b009e8 26a13b38 .config console log report info ci-upstream-gce-arm64 INFO: task hung in get_super
* Struck through repros no longer work on HEAD.