FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) INFO: task syz-executor0:5645 blocked for more than 140 seconds. Not tainted 4.20.0-rc1+ #328 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D19848 5645 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 wb_wait_for_completion+0x1f9/0x2d0 fs/fs-writeback.c:221 __writeback_inodes_sb_nr+0x405/0x580 fs/fs-writeback.c:2333 writeback_inodes_sb_nr fs/fs-writeback.c:2350 [inline] writeback_inodes_sb+0x27/0x30 fs/fs-writeback.c:2365 __sync_filesystem fs/sync.c:36 [inline] sync_filesystem+0x16f/0x330 fs/sync.c:64 generic_shutdown_super+0xdd/0x530 fs/super.c:442 kill_block_super+0x9e/0x100 fs/super.c:1185 deactivate_locked_super+0x97/0x100 fs/super.c:329 deactivate_super+0x2bb/0x320 fs/super.c:360 cleanup_mnt+0xbf/0x160 fs/namespace.c:1098 __cleanup_mnt+0x16/0x20 fs/namespace.c:1105 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459fb7 Code: Bad RIP value. RSP: 002b:00007ffc9dfe7588 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000459fb7 RDX: 0000000000402e70 RSI: 0000000000000002 RDI: 00007ffc9dfe7630 RBP: 00000000000001ee R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000005 R11: 0000000000000206 R12: 00007ffc9dfe86c0 R13: 0000000001a25940 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 3 locks held by kworker/u4:1/21: 1 lock held by khungtaskd/1008: #0: 0000000066afa34d (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 1 lock held by rsyslogd/5515: #0: 0000000069651094 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5606: #0: 0000000061b60113 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000ff6cf621 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5607: #0: 000000005ce90176 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000003cb9fa3f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5608: #0: 0000000056685ab8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000050d52f0f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5609: #0: 00000000df13225c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000365bb5ee (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5610: #0: 000000000d33b377 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000d3eab613 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5611: #0: 0000000066bf6108 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000ef6f25e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5612: #0: 000000006d9235a6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000ba21147b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 1 lock held by syz-executor0/5645: #0: 00000000adcbd0be (&type->s_umount_key#56){+.+.}, at: deactivate_super+0x2b3/0x320 fs/super.c:359 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1008 Comm: khungtaskd Not tainted 4.20.0-rc1+ #328 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 nmi_cpu_backtrace.cold.2+0x5c/0xa1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1e8/0x22a lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb51/0x1060 kernel/hung_task.c:289 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.090 msecs NMI backtrace for cpu 1 CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 4.20.0-rc1+ #328 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:__preempt_count_add arch/x86/include/asm/preempt.h:76 [inline] RIP: 0010:rcu_is_watching+0xb/0x30 kernel/rcu/tree.c:905 Code: ff ff e8 f8 66 58 00 48 8b 85 78 ff ff ff e9 21 ff ff ff e8 97 7f de ff 0f 1f 80 00 00 00 00 55 48 89 e5 65 ff 05 a5 7c 97 7e 80 fe ff ff 83 f0 01 65 ff 0d 96 7c 97 7e 74 02 5d c3 e8 dc 0b RSP: 0018:ffff8801d944dc18 EFLAGS: 00000282 RAX: 0000000000000001 RBX: ffff8801d944de28 RCX: ffffffff87cb7ccb RDX: 0000000000000000 RSI: ffffffff87cb7cde RDI: ffff8801d9442dfc RBP: ffff8801d944dc18 R08: ffff8801d9442580 R09: ffffed003b5e5b67 R10: ffffed003b5e5b67 R11: ffff8801daf2db3b R12: 0000000000000000 R13: ffff8801b65be440 R14: ffff8801c47048c2 R15: ffff8801d944dcf8 FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001d790f000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held+0x87/0xc0 kernel/rcu/update.c:277 xa_entry include/linux/xarray.h:709 [inline] xas_descend+0x413/0x510 lib/xarray.c:198 xas_load+0x145/0x1e0 lib/xarray.c:234 find_get_entry+0x3ca/0x1120 mm/filemap.c:1415 pagecache_get_page+0x12f/0xf00 mm/filemap.c:1518 find_get_page_flags include/linux/pagemap.h:278 [inline] __find_get_block_slow fs/buffer.c:205 [inline] __find_get_block+0x63a/0xf20 fs/buffer.c:1294 __getblk_slow fs/buffer.c:1039 [inline] __getblk_gfp+0x2b3/0xd50 fs/buffer.c:1320 __bread_gfp+0x2d/0x310 fs/buffer.c:1354 sb_bread include/linux/buffer_head.h:307 [inline] fat_clusters_flush+0x127/0x3c0 fs/fat/misc.c:70 fat_write_inode+0x110/0x180 fs/fat/inode.c:905 write_inode fs/fs-writeback.c:1176 [inline] __writeback_single_inode+0xf56/0x1660 fs/fs-writeback.c:1375 writeback_sb_inodes+0x71f/0x1210 fs/fs-writeback.c:1580 wb_writeback+0x48c/0xfc0 fs/fs-writeback.c:1756 wb_do_writeback fs/fs-writeback.c:1901 [inline] wb_workfn+0x495/0x1790 fs/fs-writeback.c:1942 process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352