__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 INFO: task syz-executor0:4495 blocked for more than 140 seconds. device loop0 blocksize: 4096 Not tainted 4.18.0+ #192 __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 syz-executor0 D device loop0 blocksize: 4096 17856 4495 1 0x00000004 __find_get_block_slow() failed. block=1, b_blocknr=8 Call Trace: b_state=0x00000029, b_size=512 context_switch kernel/sched/core.c:2823 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3471 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+0xfb/0x450 kernel/sched/core.c:3515 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+0x201/0x2e0 fs/fs-writeback.c:221 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 __writeback_inodes_sb_nr+0x405/0x580 fs/fs-writeback.c:2340 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 fs/fs-writeback.c:2357 [inline] writeback_inodes_sb+0x27/0x30 fs/fs-writeback.c:2372 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 generic_shutdown_super+0xdd/0x530 fs/super.c:439 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 kill_block_super+0xa4/0x100 fs/super.c:1201 deactivate_locked_super+0x97/0x100 fs/super.c:326 deactivate_super+0x2bb/0x320 fs/super.c:357 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 cleanup_mnt+0xbf/0x160 fs/namespace.c:1183 __find_get_block_slow() failed. block=1, b_blocknr=8 __cleanup_mnt+0x16/0x20 fs/namespace.c:1190 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 b_state=0x00000029, b_size=512 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 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a97 Code: Bad RIP value. b_state=0x00000029, b_size=512 RSP: 002b:00007ffe8fa507a8 EFLAGS: 00000202 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000459a97 RDX: 0000000000408440 RSI: 0000000000000002 RDI: 00007ffe8fa50850 RBP: 000000000000044c R08: 0000000000000000 R09: 000000000000000b b_state=0x00000029, b_size=512 R10: 0000000000000005 R11: 0000000000000202 R12: 00007ffe8fa518b0 R13: 000000000225f940 R14: 0000000000000000 R15: badc0ffeebadface device loop0 blocksize: 4096 Showing all locks held in the system: __find_get_block_slow() failed. block=1, b_blocknr=8 4 locks held by kworker/u4:1/22: 1 lock held by khungtaskd/774: #0: 00000000af1033a6 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 2 locks held by rs:main Q:Reg/4358: b_state=0x00000029, b_size=512 #0: 0000000080f8ef71 (&f->f_pos_lock device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 ){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 #1: 000000006df8c12b (sb_writers#6){.+.+}, at: file_start_write include/linux/fs.h:2752 [inline] #1: 000000006df8c12b (sb_writers#6){.+.+}, at: vfs_write+0x452/0x560 fs/read_write.c:548 1 lock held by rsyslogd/4360: 2 locks held by getty/4450: #0: 0000000011892a4a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: b_state=0x00000029, b_size=512 00000000fc37f77a 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 2 locks held by getty/4451: #0: 000000000a890b2e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000015d3e465 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4452: #0: 00000000c044765f b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 ( __find_get_block_slow() failed. block=1, b_blocknr=8 &tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000768a43e4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4453: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 #0: 0000000039901f36 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000005bab82cc (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4454: #0: 00000000256e0439 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 00000000c0435c22 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4455: #0: 00000000b677ea54 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000e04d2ce7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4456: #0: b_state=0x00000029, b_size=512 00000000bb31c23c ( device loop0 blocksize: 4096 &tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000690b0eaf __find_get_block_slow() failed. block=1, b_blocknr=8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 1 lock held by syz-executor0/4495: #0: 0000000037db1b8d (&type->s_umount_key#74){++++}, at: deactivate_super+0x2b3/0x320 fs/super.c:356 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 774 Comm: khungtaskd Not tainted 4.18.0+ #192 __find_get_block_slow() failed. block=1, b_blocknr=8 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+0x1c9/0x2b4 lib/dump_stack.c:113 b_state=0x00000029, b_size=512 nmi_cpu_backtrace.cold.3+0x48/0x88 lib/nmi_backtrace.c:101 device loop0 blocksize: 4096 nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 __find_get_block_slow() failed. block=1, b_blocknr=8 trigger_all_cpu_backtrace include/linux/nmi.h:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline] watchdog+0x9c4/0xf80 kernel/hung_task.c:252 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: b_state=0x00000029, b_size=512 NMI backtrace for cpu 0 CPU: 0 PID: 22 Comm: kworker/u4:1 Not tainted 4.18.0+ #192 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_pc+0x0/0x50 kernel/kcov.c:146 Code: 14 dd 28 00 00 00 4d 39 d0 72 1b 49 83 c1 01 4a 89 7c 10 e0 4a 89 74 10 e8 4a 89 54 10 f0 4a 89 4c d8 20 4c 89 08 5d c3 66 90 <55> 65 48 8b 04 25 40 ee 01 00 65 8b 15 af 1c 85 7e 48 89 e5 81 e2 RSP: 0018:ffff8801d981dbd8 EFLAGS: 00000097 RAX: ffff8801d98105c0 RBX: 0000000000000001 RCX: ffffffff86b1d779 RDX: 0000000000000000 RSI: ffffffff86b1d794 RDI: 0000000000000005 RBP: ffff8801d981dd00 R08: ffff8801d98105c0 R09: fffffbfff0ff1390 R10: fffffbfff0ff1390 R11: ffffffff87f89c83 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000021a81a8 CR3: 00000001c7352000 CR4: 00000000001406f0 DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: vsnprintf+0x13d6/0x1b60 lib/vsprintf.c:2359 snprintf+0xae/0xe0 lib/vsprintf.c:2426 print_time kernel/printk/printk.c:1221 [inline] print_prefix+0x38e/0x3f0 kernel/printk/printk.c:1246 msg_print_text+0x85/0x1c0 kernel/printk/printk.c:1269 console_unlock+0x71c/0x1110 kernel/printk/printk.c:2379 vprintk_emit+0x33a/0x910 kernel/printk/printk.c:1924 vprintk_default+0x28/0x30 kernel/printk/printk.c:1965 vprintk_func+0x7a/0x117 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:1998 __find_get_block_slow fs/buffer.c:235 [inline] __find_get_block.cold.60+0x85/0xff fs/buffer.c:1287 __getblk_slow fs/buffer.c:1032 [inline] __getblk_gfp+0x2be/0xb10 fs/buffer.c:1313 __bread_gfp+0x2d/0x310 fs/buffer.c:1347 sb_bread include/linux/buffer_head.h:307 [inline] __fat_write_inode+0x324/0xcc0 fs/fat/inode.c:864 fat_write_inode+0x97/0x180 fs/fat/inode.c:916 write_inode fs/fs-writeback.c:1183 [inline] __writeback_single_inode+0xf33/0x15e0 fs/fs-writeback.c:1382 writeback_sb_inodes+0x71f/0x11d0 fs/fs-writeback.c:1587 wb_writeback+0x470/0xf80 fs/fs-writeback.c:1763 wb_do_writeback fs/fs-writeback.c:1908 [inline] wb_workfn+0x477/0x1760 fs/fs-writeback.c:1949 process_one_work+0xc73/0x1ba0 kernel/workqueue.c:2153 worker_thread+0x189/0x13c0 kernel/workqueue.c:2296 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413