: renamed from tunl0
IPVS: Creating netns size=2536 id=12
INFO: task syz-executor3:7372 blocked for more than 120 seconds.
      Not tainted 4.9.103-g0cecdf8 #35
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D28184  7372   3889 0x00000004
 ffff8801d4618000 ffff8801d305aa00 ffff8801d3ce5a40 ffff8801d6a13000
 ffff8801db221c18 ffff88018aaffc10 ffffffff839e711d ffff880185464488
 0000000000000000 0000000000000000 0000000000000000 ffff8801db2224e8
Call Trace:
 [<ffffffff839e871f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3557
 [<ffffffff839f2b44>] rwsem_down_read_failed+0x1e4/0x320 kernel/locking/rwsem-xadd.c:260
 [<ffffffff81ee7758>] call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 [<ffffffff839f1a72>] __down_read arch/x86/include/asm/rwsem.h:65 [inline]
 [<ffffffff839f1a72>] down_read+0x52/0xb0 kernel/locking/rwsem.c:24
 [<ffffffff8157c891>] iterate_supers+0xe1/0x260 fs/super.c:591
 [<ffffffff8161a6b2>] sys_sync+0xa2/0x170 fs/sync.c:112
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f8013>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/519:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136688c>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136688c>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81425e10>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3768:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839f61c2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8211f1d2>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2133
1 lock held by syz-executor3/7372:
 #0:  (&type->s_umount_key#35){++++..}, at: [<ffffffff8157c891>] iterate_supers+0xe1/0x260 fs/super.c:591
1 lock held by syz-executor3/7401:
 #0:  (&type->s_umount_key#35){++++..}, at: [<ffffffff8157c891>] iterate_supers+0xe1/0x260 fs/super.c:591
1 lock held by syz-executor7/7380:
 #0:  (&type->s_umount_key#35){++++..}, at: [<ffffffff8157c891>] iterate_supers+0xe1/0x260 fs/super.c:591
1 lock held by syz-executor7/7405:
 #0:  (&type->s_umount_key#35){++++..}, at: [<ffffffff8157c891>] iterate_supers+0xe1/0x260 fs/super.c:591

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

NMI backtrace for cpu 0
CPU: 0 PID: 519 Comm: khungtaskd Not tainted 4.9.103-g0cecdf8 #35
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d8447d08 ffffffff81eb34a9 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810b9590 ffff8801d8447d40
 ffffffff81ebe7a7 0000000000000000 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb34a9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb34a9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebe7a7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebe73a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b9694>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81366e24>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366e24>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366e24>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366e24>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119cead>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839f81dc>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7321 Comm: syz-executor0 Not tainted 4.9.103-g0cecdf8 #35
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d6a13000 task.stack: ffff8801bf498000
RIP: 0010:[<ffffffff812346b0>] 
c [<ffffffff812346b0>] hlock_class kernel/locking/lockdep.c:149 [inline]
RIP: 0010:[<ffffffff812346b0>] 
c [<ffffffff812346b0>] mark_lock+0x90/0x1280 kernel/locking/lockdep.c:3039
RSP: 0018:ffff8801bf49f468  EFLAGS: 00000086
RAX: 0000000000000442 RBX: ffff8801d6a138c8 RCX: 1ffff1003ad4271d
RDX: 0000000000000000 RSI: ffff8801d6a138c8 RDI: ffff8801d6a13000
RBP: ffff8801bf49f4b0 R08: ffff8801d6a138e8 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff855fbdf0
R13: 0000000000000004 R14: 0000000000000002 R15: ffff8801d6a13000
FS:  00007fec6cb07700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f503f790000 CR3: 00000001ba1b9000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 000000000000008a
c 0000000000000000
c ffff8801d9c17c48
c ffff8801bf49f508
c
 0000000000000000
c ffff8801d6a138c8
c ffffed003ad42718
c ffff8801d6a13000
c
 dffffc0000000000
c ffff8801bf49f500
c ffffffff81235967
c ffff8801bf49f530
c
Call Trace:
 [<ffffffff81235967>] mark_held_locks+0xc7/0x130 kernel/locking/lockdep.c:2660
 [<ffffffff81235c36>] __trace_hardirqs_on_caller kernel/locking/lockdep.c:2681 [inline]
 [<ffffffff81235c36>] trace_hardirqs_on_caller+0x266/0x590 kernel/locking/lockdep.c:2736
 [<ffffffff8100301a>] trace_hardirqs_on_thunk+0x1a/0x1c
 [<ffffffff839f89a9>] retint_kernel+0x2d/0x2d
 [<ffffffff81624bf9>] __getblk_slow fs/buffer.c:1101 [inline]
 [<ffffffff81624bf9>] __getblk_gfp+0x189/0x710 fs/buffer.c:1386
 [<ffffffff8162859d>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818b6428>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818b6428>] fat__get_entry+0x4c8/0x8f0 fs/fat/dir.c:100
 [<ffffffff818b90b1>] fat_get_entry fs/fat/dir.c:128 [inline]
 [<ffffffff818b90b1>] fat_get_short_entry+0x131/0x2a0 fs/fat/dir.c:876
 [<ffffffff818c1017>] fat_subdirs+0xc7/0x190 fs/fat/dir.c:942
 [<ffffffff818d1329>] fat_read_root fs/fat/inode.c:1402 [inline]
 [<ffffffff818d1329>] fat_fill_super+0x1cf9/0x3550 fs/fat/inode.c:1832
 [<ffffffff818d80e1>] vfat_fill_super+0x31/0x40 fs/fat/namei_vfat.c:1070
 [<ffffffff8157c007>] mount_bdev+0x2c7/0x390 fs/super.c:1100
 [<ffffffff818d80a4>] vfat_mount+0x34/0x40 fs/fat/namei_vfat.c:1077
 [<ffffffff8157dd8c>] mount_fs+0x28c/0x370 fs/super.c:1206
 [<ffffffff815dd331>] vfs_kern_mount.part.29+0xd1/0x3d0 fs/namespace.c:991
 [<ffffffff815e4c59>] vfs_kern_mount fs/namespace.c:973 [inline]
 [<ffffffff815e4c59>] do_new_mount fs/namespace.c:2513 [inline]
 [<ffffffff815e4c59>] do_mount+0x3c9/0x2740 fs/namespace.c:2835
 [<ffffffff815e79ae>] SYSC_mount fs/namespace.c:3051 [inline]
 [<ffffffff815e79ae>] SyS_mount+0xfe/0x110 fs/namespace.c:3028
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f8013>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: 
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c14 
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cd2 
c74 
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c01 
c00 
c00 
c49 
c81 
cc4 
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c<49> 
c8d 
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c24 
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c48 
cb8 
c00 
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cdf 
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c