9pnet: p9_errstr2errno: server reported unknown error le0/flô|›j(
9pnet: Could not find request transport: bd
9pnet_virtio: no channels available for device (null)
9pnet: Could not find request transport: bd
9pnet_virtio: no channels available for device (null)
INFO: task syz-executor4:13545 blocked for more than 140 seconds.
      Not tainted 4.9.119-g9dc978d #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor4   D28168 13545  12208 0x00000004
 ffff8801c3ab9800 ffff8801d3958000 ffff88019904f9c0 ffff8801d84c6000
 ffff8801db221c18 ffff8801d6e8f660 ffffffff839ebdcd dffffc0000000000
 ffff880195d195b0 ffff8801d6e8f620 00ff8801c3aba0c0 ffff8801db2224e8
Call Trace:
 [<ffffffff839ed3cf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff815c8102>] d_wait_lookup fs/dcache.c:2455 [inline]
 [<ffffffff815c8102>] d_alloc_parallel+0xeb2/0x17c0 fs/dcache.c:2537
 [<ffffffff815950bc>] lookup_slow+0x19c/0x470 fs/namei.c:1650
 [<ffffffff815a16e6>] walk_component+0x716/0x1bb0 fs/namei.c:1784
 [<ffffffff815a4046>] lookup_last fs/namei.c:2266 [inline]
 [<ffffffff815a4046>] path_lookupat.isra.41+0x186/0x410 fs/namei.c:2283
 [<ffffffff815a9af7>] filename_lookup.part.55+0x177/0x370 fs/namei.c:2317
 [<ffffffff815a9eb3>] filename_lookup fs/namei.c:2310 [inline]
 [<ffffffff815a9eb3>] user_path_at_empty+0x53/0x70 fs/namei.c:2578
 [<ffffffff8161c16f>] user_path_at include/linux/namei.h:55 [inline]
 [<ffffffff8161c16f>] do_utimes+0x17f/0x2c0 fs/utimes.c:155
 [<ffffffff8161c84d>] SYSC_futimesat fs/utimes.c:214 [inline]
 [<ffffffff8161c84d>] SyS_futimesat fs/utimes.c:189 [inline]
 [<ffffffff8161c84d>] SYSC_utimes fs/utimes.c:220 [inline]
 [<ffffffff8161c84d>] SyS_utimes+0x13d/0x1b0 fs/utimes.c:217
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839fccd3>] 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: [<ffffffff813667bc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813667bc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81426027>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/3673:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d859c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/3769:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839fae72>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff821208d2>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor4/13528:
 #0:  (&sb->s_type->i_mutex_key#18){++++++}, at: [<ffffffff81595061>] inode_lock_shared include/linux/fs.h:776 [inline]
 #0:  (&sb->s_type->i_mutex_key#18){++++++}, at: [<ffffffff81595061>] lookup_slow+0x141/0x470 fs/namei.c:1645
1 lock held by syz-executor4/13545:
 #0:  (&sb->s_type->i_mutex_key#18){++++++}, at: [<ffffffff81595061>] inode_lock_shared include/linux/fs.h:776 [inline]
 #0:  (&sb->s_type->i_mutex_key#18){++++++}, at: [<ffffffff81595061>] lookup_slow+0x141/0x470 fs/namei.c:1645

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

NMI backtrace for cpu 1
CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.119-g9dc978d #23
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d867fd08 ffffffff81eb4be9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9bd0 ffff8801d867fd40
 ffffffff81ebfee7 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb4be9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb4be9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebfee7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebfe7a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b9cd4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81366d54>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366d54>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366d54>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366d54>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119d0ed>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839fce9c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.119-g9dc978d #23
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffffffff84629800 task.stack: ffffffff84600000
RIP: 0010:[<ffffffff839fef30>] 
c [<ffffffff839fef30>] reschedule_interrupt+0x0/0xb0 arch/x86/entry/entry_64.S:670
RSP: 0018:ffffffff84607d98  EFLAGS: 00000046
RAX: 0000000000000007 RBX: ffffffff84c4ea48 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff8462a0c4
RBP: ffffffff84607dc0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff84c5eb88 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdaec755000 CR3: 00000001c0818000 CR4: 00000000001606f0
Stack:
 ffffffff839fb8d6
c 0000000000000010
c 0000000000000246
c ffffffff84607dc0
c
 0000000000000018
c ffffffff84607df8
c ffffffff839faf15
c ffffffff84629800
c
 0000000000000000
c dffffc0000000000
c ffffffff84c5eb88
c 0000000000000000
c
Call Trace:
 [<ffffffff839faf15>] arch_safe_halt arch/x86/include/asm/paravirt.h:104 [inline]
 [<ffffffff839faf15>] default_idle+0x55/0x360 arch/x86/kernel/process.c:437
 [<ffffffff8106ae20>] arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:428
 [<ffffffff839fbd35>] default_idle_call+0x45/0x60 kernel/sched/idle.c:97
 [<ffffffff812231b5>] cpuidle_idle_call kernel/sched/idle.c:155 [inline]
 [<ffffffff812231b5>] cpu_idle_loop kernel/sched/idle.c:248 [inline]
 [<ffffffff812231b5>] cpu_startup_entry+0x2b5/0x380 kernel/sched/idle.c:303
 [<ffffffff839e8b9c>] rest_init+0x183/0x189 init/main.c:409
 [<ffffffff84c97943>] start_kernel+0x67e/0x6b2 init/main.c:664
 [<ffffffff84c9629a>] x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:196
 [<ffffffff84c963db>] x86_64_start_kernel+0x13f/0x162 arch/x86/kernel/head64.c:177
Code: 
c04 
c25 
c54 
c7d 
c01 
c00 
c65 
c48 
c0f 
c44 
c24 
c25 
c58 
c7d 
c01 
c00 
c57 
ce8 
c01 
c41 
c60 
cfd 
ce8 
cf0 
c2a 
c00 
c00 
ce9 
cbb 
ce6 
cff 
cff 
c90 
c66 
c2e 
c0f 
c1f 
c84 
c00 
c00 
c00 
c00 
c00 
c<0f> 
c1f 
c00 
c68 
c02 
cff 
cff 
cff 
cfc 
c48 
c83 
cc4 
c88 
c4c 
c89 
c5c 
c24 
c30 
c4c 
c89 
c54 
c