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 INFO: task syz-executor0:5538 blocked for more than 140 seconds. __find_get_block_slow() failed. block=1, b_blocknr=8 Not tainted 4.19.0-rc5+ #40 b_state=0x00000029, b_size=512 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. device loop0 blocksize: 4096 syz-executor0 D19016 5538 1 0x00000004 __find_get_block_slow() failed. block=1, b_blocknr=8 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 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 b_state=0x00000029, b_size=512 wb_wait_for_completion+0x1f9/0x2d0 fs/fs-writeback.c:221 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 __writeback_inodes_sb_nr+0x405/0x580 fs/fs-writeback.c:2340 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 writeback_inodes_sb_nr fs/fs-writeback.c:2357 [inline] writeback_inodes_sb+0x27/0x30 fs/fs-writeback.c:2372 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __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 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 generic_shutdown_super+0xdd/0x530 fs/super.c:442 __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 cleanup_mnt+0xbf/0x160 fs/namespace.c:1098 device loop0 blocksize: 4096 __cleanup_mnt+0x16/0x20 fs/namespace.c:1105 __find_get_block_slow() failed. block=1, b_blocknr=8 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 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 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 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 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 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 entry_SYSCALL_64_after_hwframe+0x49/0xbe device loop0 blocksize: 4096 RIP: 0033:0x459fc7 __find_get_block_slow() failed. block=1, b_blocknr=8 Code: Bad RIP value. b_state=0x00000029, b_size=512 RSP: 002b:00007ffdf3dec278 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 device loop0 blocksize: 4096 RAX: 0000000000000000 RBX: 00000000000453eb RCX: 0000000000459fc7 RDX: 0000000000402e70 RSI: 0000000000000002 RDI: 00007ffdf3dec320 __find_get_block_slow() failed. block=1, b_blocknr=8 RBP: 00000000000001fa R08: 0000000000000000 R09: 000000000000000a b_state=0x00000029, b_size=512 R10: 0000000000000005 R11: 0000000000000202 R12: 00007ffdf3ded3b0 R13: 00000000019b5940 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 6 locks held by kworker/u4:0/7: b_state=0x00000029, b_size=512 1 lock held by khungtaskd/985: #0: 00000000ea4f44b8 device loop0 blocksize: 4096 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4435 1 lock held by rsyslogd/5372: 2 locks held by getty/5495: __find_get_block_slow() failed. block=1, b_blocknr=8 #0: b_state=0x00000029, b_size=512 0000000004cc2a0f device loop0 blocksize: 4096 ( __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 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 00000000ac4875e2 b_state=0x00000029, b_size=512 ( device loop0 blocksize: 4096 &ldata->atomic_read_lock __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: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 b_state=0x00000029, b_size=512 2 locks held by getty/5496: device loop0 blocksize: 4096 #0: __find_get_block_slow() failed. block=1, b_blocknr=8 00000000789268df 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 00000000b2a30d57 ( device loop0 blocksize: 4096 &ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5497: __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 000000006f7320cf 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 &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 00000000e58ed6fa ( 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 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/5498: b_state=0x00000029, b_size=512 #0: 000000000822f9af device loop0 blocksize: 4096 ( __find_get_block_slow() failed. block=1, b_blocknr=8 &tty->ldisc_sem 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 , at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 b_state=0x00000029, b_size=512 #1: device loop0 blocksize: 4096 00000000214ba84b ( __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 ){+.+.} 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 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/5499: b_state=0x00000029, b_size=512 #0: 000000000bc5c0af device loop0 blocksize: 4096 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: __find_get_block_slow() failed. block=1, b_blocknr=8 000000005c9c0a20 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 &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/5500: b_state=0x00000029, b_size=512 #0: device loop0 blocksize: 4096 00000000a252b921 __find_get_block_slow() failed. block=1, b_blocknr=8 ( b_state=0x00000029, b_size=512 &tty->ldisc_sem 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 , at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 #1: __find_get_block_slow() failed. block=1, b_blocknr=8 0000000045f160e5 b_state=0x00000029, b_size=512 ( device loop0 blocksize: 4096 &ldata->atomic_read_lock __find_get_block_slow() failed. block=1, b_blocknr=8 ){+.+.} 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/5501: b_state=0x00000029, b_size=512 #0: device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 00000000979401b7 b_state=0x00000029, b_size=512 ( device loop0 blocksize: 4096 &tty->ldisc_sem __find_get_block_slow() failed. block=1, b_blocknr=8 ){++++} b_state=0x00000029, b_size=512 , at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 device loop0 blocksize: 4096 #1: __find_get_block_slow() failed. block=1, b_blocknr=8 00000000b669c9e3 b_state=0x00000029, b_size=512 ( 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 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 1 lock held by syz-executor0/5538: b_state=0x00000029, b_size=512 #0: device loop0 blocksize: 4096 00000000a0b7fd96 __find_get_block_slow() failed. block=1, b_blocknr=8 ( b_state=0x00000029, b_size=512 &type->s_umount_key device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 #59 b_state=0x00000029, b_size=512 ){+.+.} device loop0 blocksize: 4096 , at: deactivate_super+0x2b3/0x320 fs/super.c:359 __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 NMI backtrace for cpu 1 b_state=0x00000029, b_size=512 CPU: 1 PID: 985 Comm: khungtaskd Not tainted 4.19.0-rc5+ #40 device loop0 blocksize: 4096 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 __find_get_block_slow() failed. block=1, b_blocknr=8 Call Trace: b_state=0x00000029, b_size=512 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed 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: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 kthread+0x35a/0x420 kernel/kthread.c:246 device loop0 blocksize: 4096 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: 7 Comm: kworker/u4:0 Not tainted 4.19.0-rc5+ #40 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:inb arch/x86/include/asm/io.h:333 [inline] RIP: 0010:io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:449 Code: e1 00 00 00 49 8d 7c 24 38 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 17 41 03 5c 24 38 89 da ec <5b> 0f b6 c0 41 5c 5d c3 e8 c8 2f e5 fd eb c2 e8 21 30 e5 fd eb e2 RSP: 0018:ffff8801d9ad5d90 EFLAGS: 00000006 RAX: dffffc0000000005 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: ffffffff83dce591 RDI: ffffffff8b8e7498 RBP: ffff8801d9ad5da0 R08: fffffbfff171ce8d R09: fffffbfff171ce8c R10: fffffbfff171ce8c R11: ffffffff8b8e7463 R12: ffffffff8b8e7460 R13: ffffffff8b8e7680 R14: 0000000000000001 R15: ffffffff8b8e74a8 FS: 0000000000000000(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001d2f20000 CR4: 00000000001406f0 DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: serial_port_in include/linux/serial_core.h:268 [inline] serial8250_console_write+0x2c5/0xb10 drivers/tty/serial/8250/8250_port.c:3252 univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:590 call_console_drivers kernel/printk/printk.c:1724 [inline] console_unlock+0xcd7/0x1160 kernel/printk/printk.c:2405 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 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.192 msecs