device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 INFO: task syz-executor0:5345 blocked for more than 140 seconds. b_state=0x00000029, b_size=512 Not tainted 4.19.0-rc5+ #260 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 syz-executor0 D __find_get_block_slow() failed. block=1, b_blocknr=8 18944 5345 1 0x00000004 b_state=0x00000029, b_size=512 Call Trace: device loop0 blocksize: 4096 context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 schedule+0xfe/0x460 kernel/sched/core.c:3517 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 wb_wait_for_completion+0x1f9/0x2d0 fs/fs-writeback.c:221 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __writeback_inodes_sb_nr+0x405/0x580 fs/fs-writeback.c:2340 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 writeback_inodes_sb_nr fs/fs-writeback.c:2357 [inline] writeback_inodes_sb+0x27/0x30 fs/fs-writeback.c:2372 __find_get_block_slow() failed. block=1, b_blocknr=8 __sync_filesystem fs/sync.c:36 [inline] sync_filesystem+0x16f/0x330 fs/sync.c:64 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 generic_shutdown_super+0xdd/0x530 fs/super.c:442 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 kill_block_super+0x9e/0x100 fs/super.c:1185 device loop0 blocksize: 4096 deactivate_locked_super+0x97/0x100 fs/super.c:329 __find_get_block_slow() failed. block=1, b_blocknr=8 deactivate_super+0x2bb/0x320 fs/super.c:360 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 cleanup_mnt+0xbf/0x160 fs/namespace.c:1098 __find_get_block_slow() failed. block=1, b_blocknr=8 __cleanup_mnt+0x16/0x20 fs/namespace.c:1105 b_state=0x00000029, b_size=512 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 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 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 entry_SYSCALL_64_after_hwframe+0x49/0xbe __find_get_block_slow() failed. block=1, b_blocknr=8 RIP: 0033:0x459fc7 b_state=0x00000029, b_size=512 Code: Bad RIP value. device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 RSP: 002b:00007fffebb20a88 EFLAGS: 00000206 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 ORIG_RAX: 00000000000000a6 __find_get_block_slow() failed. block=1, b_blocknr=8 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000459fc7 b_state=0x00000029, b_size=512 RDX: 0000000000402e70 RSI: 0000000000000002 RDI: 00007fffebb20b30 device loop0 blocksize: 4096 RBP: 00000000000001c2 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000005 R11: 0000000000000206 R12: 00007fffebb21bc0 __find_get_block_slow() failed. block=1, b_blocknr=8 R13: 0000000001057940 R14: 0000000000000000 R15: 0000000000000000 b_state=0x00000029, b_size=512 Showing all locks held in the system: device loop0 blocksize: 4096 6 locks held by kworker/u4:2/30: __find_get_block_slow() failed. block=1, b_blocknr=8 1 lock held by khungtaskd/982: b_state=0x00000029, b_size=512 #0: 0000000020418c84 device loop0 blocksize: 4096 ( __find_get_block_slow() failed. block=1, b_blocknr=8 rcu_read_lock b_state=0x00000029, b_size=512 ){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4435 device loop0 blocksize: 4096 1 lock held by rsyslogd/5215: __find_get_block_slow() failed. block=1, b_blocknr=8 #0: b_state=0x00000029, b_size=512 000000000c854fad ( device loop0 blocksize: 4096 &f->f_pos_lock){+.+.} __find_get_block_slow() failed. block=1, b_blocknr=8 , at: __fdget_pos+0x1bb/0x200 fs/file.c:766 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/5305: b_state=0x00000029, b_size=512 #0: 000000000d583124 device loop0 blocksize: 4096 (&tty->ldisc_sem __find_get_block_slow() failed. block=1, b_blocknr=8 ){++++} b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 , at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 #1: b_state=0x00000029, b_size=512 00000000b98af300 ( device loop0 blocksize: 4096 &ldata->atomic_read_lock __find_get_block_slow() failed. block=1, b_blocknr=8 ){+.+.} b_state=0x00000029, b_size=512 , at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5306: device loop0 blocksize: 4096 #0: 00000000e032668f __find_get_block_slow() failed. block=1, b_blocknr=8 ( b_state=0x00000029, b_size=512 &tty->ldisc_sem){++++} device loop0 blocksize: 4096 , at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 __find_get_block_slow() failed. block=1, b_blocknr=8 #1: b_state=0x00000029, b_size=512 00000000f7cf7c3d ( device loop0 blocksize: 4096 &ldata->atomic_read_lock){+.+.} __find_get_block_slow() failed. block=1, b_blocknr=8 , at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 b_state=0x00000029, b_size=512 2 locks held by getty/5307: device loop0 blocksize: 4096 #0: 00000000540c13ba (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 __find_get_block_slow() failed. block=1, b_blocknr=8 #1: b_state=0x00000029, b_size=512 00000000094474f6 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 ( b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 &ldata->atomic_read_lock b_state=0x00000029, b_size=512 ){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 device loop0 blocksize: 4096 2 locks held by getty/5308: __find_get_block_slow() failed. block=1, b_blocknr=8 #0: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 00000000692e7129 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 ( b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 &tty->ldisc_sem){++++} __find_get_block_slow() failed. block=1, b_blocknr=8 , at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 b_state=0x00000029, b_size=512 #1: device loop0 blocksize: 4096 000000009cfe9913 __find_get_block_slow() failed. block=1, b_blocknr=8 ( b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 &ldata->atomic_read_lock b_state=0x00000029, b_size=512 ){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5309: device loop0 blocksize: 4096 #0: __find_get_block_slow() failed. block=1, b_blocknr=8 00000000553aecad b_state=0x00000029, b_size=512 ( device loop0 blocksize: 4096 &tty->ldisc_sem){++++} __find_get_block_slow() failed. block=1, b_blocknr=8 , at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 #1: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 00000000420f0694 b_state=0x00000029, b_size=512 (&ldata->atomic_read_lock device loop0 blocksize: 4096 ){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/5310: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 #0: device loop0 blocksize: 4096 00000000f0083953 ( __find_get_block_slow() failed. block=1, b_blocknr=8 &tty->ldisc_sem b_state=0x00000029, b_size=512 ){++++} device loop0 blocksize: 4096 , at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 __find_get_block_slow() failed. block=1, b_blocknr=8 #1: b_state=0x00000029, b_size=512 0000000057ad078e device loop0 blocksize: 4096 ( __find_get_block_slow() failed. block=1, b_blocknr=8 &ldata->atomic_read_lock b_state=0x00000029, b_size=512 ){+.+.} device loop0 blocksize: 4096 , at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/5311: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 #0: __find_get_block_slow() failed. block=1, b_blocknr=8 00000000da5179bb b_state=0x00000029, b_size=512 ( device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 &tty->ldisc_sem b_state=0x00000029, b_size=512 ){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 device loop0 blocksize: 4096 #1: 00000000ef7526ed __find_get_block_slow() failed. block=1, b_blocknr=8 ( b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 &ldata->atomic_read_lock b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 ){+.+.} __find_get_block_slow() failed. block=1, b_blocknr=8 , at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 b_state=0x00000029, b_size=512 1 lock held by syz-executor0/5345: device loop0 blocksize: 4096 #0: __find_get_block_slow() failed. block=1, b_blocknr=8 00000000c90aeff6 b_state=0x00000029, b_size=512 ( device loop0 blocksize: 4096 &type->s_umount_key __find_get_block_slow() failed. block=1, b_blocknr=8 #47){+.+.}, at: deactivate_super+0x2b3/0x320 fs/super.c:359 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 ============================================= __find_get_block_slow() failed. block=1, b_blocknr=8 NMI backtrace for cpu 1 b_state=0x00000029, b_size=512 CPU: 1 PID: 982 Comm: khungtaskd Not tainted 4.19.0-rc5+ #260 device loop0 blocksize: 4096 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __find_get_block_slow() failed. block=1, b_blocknr=8 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed lib/nmi_backtrace.c:62 __find_get_block_slow() failed. block=1, b_blocknr=8 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 b_state=0x00000029, b_size=512 trigger_all_cpu_backtrace include/linux/nmi.h:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb3e/0x1050 kernel/hung_task.c:265 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 1 to CPUs 0: __find_get_block_slow() failed. block=1, b_blocknr=8 NMI backtrace for cpu 0 CPU: 0 PID: 30 Comm: kworker/u4:2 Not tainted 4.19.0-rc5+ #260 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:__sanitizer_cov_trace_cmp8+0x0/0x20 kernel/kcov.c:163 Code: ff ff 5d c3 66 0f 1f 44 00 00 55 89 f2 89 fe bf 04 00 00 00 48 89 e5 48 8b 4d 08 e8 ea fe ff ff 5d c3 0f 1f 84 00 00 00 00 00 <55> 48 89 f2 48 89 fe bf 06 00 00 00 48 89 e5 48 8b 4d 08 e8 c8 fe RSP: 0018:ffff8801d951db98 EFLAGS: 00000093 RAX: ffff8801d9486080 RBX: 00000000000001b0 RCX: ffffffff87abf199 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00000000000001b0 RBP: ffff8801d951dcc0 R08: ffff8801d9486080 R09: fffffbfff12720ec R10: fffffbfff12720ec R11: ffffffff89390763 R12: 000000000000000a R13: 000000000000000a R14: 0000000000000000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001bdce3000 CR4: 00000000001406f0 Call Trace: vsnprintf+0x13d0/0x1b60 lib/vsprintf.c:2359 snprintf+0xae/0xe0 lib/vsprintf.c:2426 print_time kernel/printk/printk.c:1222 [inline] print_prefix+0x38e/0x3f0 kernel/printk/printk.c:1247 msg_print_text+0x83/0x1d0 kernel/printk/printk.c:1270 console_unlock+0x4d6/0x1160 kernel/printk/printk.c:2379 vprintk_emit+0x33d/0x930 kernel/printk/printk.c:1922 vprintk_default+0x28/0x30 kernel/printk/printk.c:1963 vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:1996 __find_get_block_slow fs/buffer.c:231 [inline] __find_get_block.cold.57+0x3a/0xff fs/buffer.c:1294 __getblk_slow fs/buffer.c:1039 [inline] __getblk_gfp+0x2b3/0xd50 fs/buffer.c:1320 __bread_gfp+0x2d/0x300 fs/buffer.c:1354 sb_bread include/linux/buffer_head.h:307 [inline] __fat_write_inode+0x347/0xb60 fs/fat/inode.c:859 fat_write_inode+0x97/0x180 fs/fat/inode.c:908 write_inode fs/fs-writeback.c:1183 [inline] __writeback_single_inode+0xf1f/0x1620 fs/fs-writeback.c:1382 writeback_sb_inodes+0x71f/0x11d0 fs/fs-writeback.c:1587 wb_writeback+0x48c/0xfc0 fs/fs-writeback.c:1763 wb_do_writeback fs/fs-writeback.c:1908 [inline] wb_workfn+0x495/0x1790 fs/fs-writeback.c:1949 process_one_work+0xc90/0x1b90 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413