FAT-fs (loop6): Can't find a valid FAT filesystem FAT-fs (loop6): Unrecognized mount option "security" or missing value INFO: task syz-executor0:7962 blocked for more than 120 seconds. Not tainted 4.9.109-g7cecc75 #2 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D27976 7962 1 0x00000002 ffff8801d41f4800 ffff8801b6c98540 ffff8801ccaacfc0 ffff8801cb2bc800 ffff8801db221c18 ffff8801b887f9d8 ffffffff839e8a3d ffffffff812355f7 0000000000000000 ffff8801d41f50c0 0000000600000007 ffff8801db2224e8 Call Trace: [] schedule+0x7f/0x1b0 kernel/sched/core.c:3557 [] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline] [] rwsem_down_write_failed+0x598/0x990 kernel/locking/rwsem-xadd.c:555 [] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105 [] __down_write arch/x86/include/asm/rwsem.h:125 [inline] [] down_write+0x5c/0xa0 kernel/locking/rwsem.c:54 [] deactivate_super+0x89/0xd0 fs/super.c:340 [] cleanup_mnt+0xb2/0x160 fs/namespace.c:1134 [] __cleanup_mnt+0x16/0x20 fs/namespace.c:1141 [] task_work_run+0x10c/0x180 kernel/task_work.c:116 [] exit_task_work include/linux/task_work.h:21 [inline] [] do_exit+0x9e1/0x27c0 kernel/exit.c:837 [] do_group_exit+0x111/0x340 kernel/exit.c:941 [] SYSC_exit_group kernel/exit.c:952 [inline] [] SyS_exit_group+0x1d/0x20 kernel/exit.c:950 [] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 [] 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: [] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline] #0: (rcu_read_lock){......}, at: [] watchdog+0x11c/0xa20 kernel/hung_task.c:239 #1: (tasklist_lock){.+.?..}, at: [] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336 2 locks held by getty/3777: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2133 1 lock held by syz-executor0/7962: #0: (&type->s_umount_key#35){++++..}, at: [] deactivate_super+0x89/0xd0 fs/super.c:340 1 lock held by syz-executor4/16115: #0: (&type->s_umount_key#35){++++..}, at: [] iterate_supers+0xe1/0x260 fs/super.c:591 1 lock held by syz-executor4/16183: #0: (&type->s_umount_key#35){++++..}, at: [] iterate_supers+0xe1/0x260 fs/super.c:591 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 519 Comm: khungtaskd Not tainted 4.9.109-g7cecc75 #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801d8617d08 ffffffff81eb3e29 0000000000000000 0000000000000000 0000000000000000 0000000000000001 ffffffff810b9580 ffff8801d8617d40 ffffffff81ebf127 0000000000000000 0000000000000000 0000000000000002 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99 [] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60 [] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 [] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline] [] check_hung_task kernel/hung_task.c:125 [inline] [] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline] [] watchdog+0x6b4/0xa20 kernel/hung_task.c:239 [] kthread+0x26d/0x300 kernel/kthread.c:211 [] 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: 19262 Comm: kworker/u4:10 Not tainted 4.9.109-g7cecc75 #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfnc (flush-7:0)c task: ffff8801cbbcb000 task.stack: ffff8801b6e88000 RIP: 0010:[] c [] __lock_is_held+0x8e/0xf0 kernel/locking/lockdep.c:3594 RSP: 0018:ffff8801b6e8f4b8 EFLAGS: 00000006 RAX: 0000000000000000 RBX: ffff8801cbbcb000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff846defa0 RDI: ffff8801cbbcb912 RBP: ffff8801b6e8f4e8 R08: ffff8801cbbcb988 R09: 0000000000000001 R10: ffff8801cbbcb000 R11: 1ffff1003977972c R12: ffffed0039779718 R13: ffff8801cbbcb8c8 R14: ffffffff846defa0 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c4556ad000 CR3: 00000001c3354000 CR4: 00000000001606f0 DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Stack: ffff8801cbbcb8c0c 0000000000000246c ffff8801cbbcb000c ffffffff846defa0c 0000000000000000c ffff8801cbfe6548c ffff8801b6e8f510c ffffffff81230a04c ffffea00070c4b80c ffff88016c168b30c dffffc0000000000c ffff8801b6e8f520c Call Trace: [] lock_is_held+0xb4/0x140 kernel/locking/lockdep.c:3794 [] rcu_read_lock_held+0xa4/0xc0 kernel/rcu/update.c:297 [] radix_tree_deref_slot include/linux/radix-tree.h:199 [inline] [] find_get_entry+0x34b/0x540 mm/filemap.c:1097 [] pagecache_get_page+0x4b/0x720 mm/filemap.c:1203 [] find_get_page_flags include/linux/pagemap.h:264 [inline] [] __find_get_block_slow+0xc2/0x330 fs/buffer.c:212 [] __find_get_block+0x23e/0x4c0 fs/buffer.c:1360 [] __getblk_slow fs/buffer.c:1101 [inline] [] __getblk_gfp+0x189/0x710 fs/buffer.c:1386 [] __bread_gfp+0x2d/0x270 fs/buffer.c:1420 [] sb_bread include/linux/buffer_head.h:300 [inline] [] fat_clusters_flush+0x111/0x380 fs/fat/misc.c:69 [] fat_write_inode+0xf2/0x170 fs/fat/inode.c:890 [] write_inode fs/fs-writeback.c:1180 [inline] [] __writeback_single_inode+0x86d/0x1020 fs/fs-writeback.c:1379 [] writeback_sb_inodes+0x4ac/0xe70 fs/fs-writeback.c:1584 [] __writeback_inodes_wb+0xfb/0x1e0 fs/fs-writeback.c:1653 [] wb_writeback+0x512/0xbd0 fs/fs-writeback.c:1762 [] wb_check_old_data_flush fs/fs-writeback.c:1877 [inline] [] wb_do_writeback fs/fs-writeback.c:1901 [inline] [] wb_workfn+0x850/0xdb0 fs/fs-writeback.c:1930 [] process_one_work+0x7e1/0x1500 kernel/workqueue.c:2092 [] worker_thread+0xd6/0x10a0 kernel/workqueue.c:2226 [] kthread+0x26d/0x300 kernel/kthread.c:211 [] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373 Code: cec c03 c49 c01 cc4 c8b c83 cc0 c08 c00 c00 c85 cc0 c7f c1c ceb c46 c41 c0f cb6 c04 c24 c41 c83 cc7 c01 c84 cc0 c74 c04 c3c c03 c7e c54 c44 c39 cbb cc0 c08 c00 c00 c7e c2c c<49> c63 cc7 c4c c89 cf6 c48 c8d c04 c80 c49 c8d c7c cc5 c00 ce8 cee cf9 cff cff c85 c