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-executor0:15186 blocked for more than 140 seconds. b_state=0x00000029, b_size=512 Not tainted 4.19.0-rc8-next-20181019+ #98 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 D24648 15186 5618 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:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3480 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 schedule+0xfe/0x460 kernel/sched/core.c:3524 __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 __rwsem_down_write_failed_common+0xc9a/0x15e0 kernel/locking/rwsem-xadd.c:577 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 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 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:606 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 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0xa5/0x130 kernel/locking/rwsem.c:72 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 inode_lock include/linux/fs.h:764 [inline] do_last fs/namei.c:3321 [inline] path_openat+0x15c4/0x5150 fs/namei.c:3534 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 do_filp_open+0x255/0x380 fs/namei.c:3564 __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 do_sys_open+0x568/0x700 fs/open.c:1063 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 ksys_open include/linux/syscalls.h:1292 [inline] __do_sys_creat fs/open.c:1121 [inline] __se_sys_creat fs/open.c:1119 [inline] __x64_sys_creat+0x61/0x80 fs/open.c:1119 device loop0 blocksize: 4096 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 __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 entry_SYSCALL_64_after_hwframe+0x49/0xbe __find_get_block_slow() failed. block=1, b_blocknr=8 RIP: 0033:0x457569 b_state=0x00000029, b_size=512 Code: Bad RIP value. device loop0 blocksize: 4096 RSP: 002b:00007fa58f60bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 __find_get_block_slow() failed. block=1, b_blocknr=8 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457569 b_state=0x00000029, b_size=512 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000180 device loop0 blocksize: 4096 RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000 __find_get_block_slow() failed. block=1, b_blocknr=8 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa58f60c6d4 b_state=0x00000029, b_size=512 R13: 00000000004bdb2f R14: 00000000004cc688 R15: 00000000ffffffff device loop0 blocksize: 4096 Showing all locks held in the system: __find_get_block_slow() failed. block=1, b_blocknr=8 1 lock held by khungtaskd/983: b_state=0x00000029, b_size=512 #0: 000000008edb1ec2 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 device loop0 blocksize: 4096 1 lock held by rsyslogd/5489: __find_get_block_slow() failed. block=1, b_blocknr=8 #0: 00000000fcf5d558 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 b_state=0x00000029, b_size=512 2 locks held by getty/5578: device loop0 blocksize: 4096 #0: 000000008cfa7408 (&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: 00000000bbf928ca (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 2 locks held by getty/5579: __find_get_block_slow() failed. block=1, b_blocknr=8 #0: 00000000c9b8a09a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 b_state=0x00000029, b_size=512 #1: 000000002337bc5c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 2 locks held by getty/5580: device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 #0: 00000000d8fe30a3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 b_state=0x00000029, b_size=512 #1: 000000004a4fc416 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 device loop0 blocksize: 4096 2 locks held by getty/5581: __find_get_block_slow() failed. block=1, b_blocknr=8 #0: 000000008abf1d34 (&tty->ldisc_sem){++++}, 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: 00000000413b7738 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 b_state=0x00000029, b_size=512 2 locks held by getty/5582: device loop0 blocksize: 4096 #0: 00000000b29b8fd1 (&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: 0000000045e2effc (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 b_state=0x00000029, b_size=512 2 locks held by getty/5583: device loop0 blocksize: 4096 #0: 00000000c609eddf (&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: 000000008bb8de66 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 b_state=0x00000029, b_size=512 2 locks held by getty/5584: device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 #0: 0000000052672e15 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 b_state=0x00000029, b_size=512 #1: 000000008a677ace (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 device loop0 blocksize: 4096 7 locks held by syz-executor0/15136: __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by syz-executor0/15186: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 #0: 0000000066c6c5db (sb_writers#19){.+.+}, at: sb_start_write include/linux/fs.h:1602 [inline] #0: 0000000066c6c5db (sb_writers#19){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:359 __find_get_block_slow() failed. block=1, b_blocknr=8 #1: 00000000ce469a2c (&sb->s_type->i_mutex_key#26){++++}, at: inode_lock include/linux/fs.h:764 [inline] #1: 00000000ce469a2c (&sb->s_type->i_mutex_key#26){++++}, at: do_last fs/namei.c:3321 [inline] #1: 00000000ce469a2c (&sb->s_type->i_mutex_key#26){++++}, at: path_openat+0x15c4/0x5150 fs/namei.c:3534 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 ============================================= __find_get_block_slow() failed. block=1, b_blocknr=8 NMI backtrace for cpu 0 b_state=0x00000029, b_size=512 CPU: 0 PID: 983 Comm: khungtaskd Not tainted 4.19.0-rc8-next-20181019+ #98 device loop0 blocksize: 4096 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 __find_get_block_slow() failed. block=1, b_blocknr=8 nmi_trigger_cpumask_backtrace+0x1e8/0x22a lib/nmi_backtrace.c:62 b_state=0x00000029, b_size=512 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 device loop0 blocksize: 4096 trigger_all_cpu_backtrace include/linux/nmi.h:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb39/0x1050 kernel/hung_task.c:265 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 kthread+0x35a/0x440 kernel/kthread.c:246 __find_get_block_slow() failed. block=1, b_blocknr=8 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: b_state=0x00000029, b_size=512 NMI backtrace for cpu 1 CPU: 1 PID: 15136 Comm: syz-executor0 Not tainted 4.19.0-rc8-next-20181019+ #98 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x1/0x50 kernel/kcov.c:94 Code: 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 <48> 89 e5 48 8b 75 08 65 48 8b 04 25 40 ee 01 00 65 8b 15 e8 b9 82 RSP: 0018:ffff8801875be490 EFLAGS: 00000046 RAX: ffff8801875be588 RBX: 0000000000000240 RCX: ffffc90001e6a000 RDX: 0000000000040000 RSI: 0000000000000240 RDI: ffff8801875be588 RBP: ffff8801875be4c0 R08: ffff88017e1662c0 R09: ffffed0030eb7cf5 R10: ffffed0030eb7cf5 R11: 0000000000000003 R12: ffff8801875be588 R13: 000000000000000a R14: 0000000000000000 R15: 0000000000000001 FS: 00007fa58f64e700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001cd766000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: number+0xb94/0xca0 lib/vsprintf.c:467 vsnprintf+0x13d0/0x1b60 lib/vsprintf.c:2362 snprintf+0xae/0xe0 lib/vsprintf.c:2429 print_time kernel/printk/printk.c:1226 [inline] print_prefix+0x38e/0x3f0 kernel/printk/printk.c:1251 msg_print_text+0x83/0x1d0 kernel/printk/printk.c:1274 console_unlock+0x4e6/0x1190 kernel/printk/printk.c:2388 vprintk_emit+0x391/0x990 kernel/printk/printk.c:1922 vprintk_default+0x28/0x30 kernel/printk/printk.c:1964 vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:1997 __find_get_block_slow fs/buffer.c:235 [inline] __find_get_block.cold.58+0x85/0xff fs/buffer.c:1325 __getblk_slow fs/buffer.c:1058 [inline] __getblk_gfp+0x3d3/0x1030 fs/buffer.c:1351 __bread_gfp+0x2d/0x310 fs/buffer.c:1385 sb_bread include/linux/buffer_head.h:307 [inline] fat__get_entry+0x5a6/0xa40 fs/fat/dir.c:101 fat_get_entry fs/fat/dir.c:129 [inline] fat_search_long+0x33b/0x1570 fs/fat/dir.c:479 vfat_find+0x16d/0x1a0 fs/fat/namei_vfat.c:697 vfat_lookup+0x107/0x640 fs/fat/namei_vfat.c:711 lookup_open+0x72e/0x1b90 fs/namei.c:3213 do_last fs/namei.c:3324 [inline] path_openat+0x15e4/0x5150 fs/namei.c:3534 do_filp_open+0x255/0x380 fs/namei.c:3564 do_sys_open+0x568/0x700 fs/open.c:1063 ksys_open include/linux/syscalls.h:1292 [inline] __do_sys_creat fs/open.c:1121 [inline] __se_sys_creat fs/open.c:1119 [inline] __x64_sys_creat+0x61/0x80 fs/open.c:1119 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fa58f64dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000180 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa58f64e6d4 R13: 00000000004bdb2f R14: 00000000004cc688 R15: 00000000ffffffff INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.995 msecs