syz-executor0(22589): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor0(22589): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor0(22589): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor0(22589): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor0(22589): getblk(): executed=9 bh_count=0 bh_state=0 INFO: task syz-executor0:22599 blocked for more than 140 seconds. Not tainted 4.20.0-rc1-next-20181109+ #110 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D24872 22599 5950 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xef/0x370 kernel/sched/core.c:3516 d_wait_lookup fs/dcache.c:2408 [inline] d_alloc_parallel+0x1478/0x1f40 fs/dcache.c:2490 lookup_open+0x560/0x1b90 fs/namei.c:3147 do_last fs/namei.c:3324 [inline] path_openat+0x2464/0x5150 fs/namei.c:3534 do_filp_open+0x255/0x380 fs/namei.c:3564 do_sys_open+0x568/0x700 fs/open.c:1063 __do_sys_openat fs/open.c:1090 [inline] __se_sys_openat fs/open.c:1084 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1084 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: Bad RIP value. RSP: 002b:00007f1a18118c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569 RDX: 0000000000000002 RSI: 0000000020000080 RDI: 0000000000000004 RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1a181196d4 R13: 00000000004c2e2f R14: 00000000004d4d98 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1010: #0: 0000000091389d0b (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 1 lock held by rsyslogd/5816: #0: 00000000601ef41e (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5906: #0: 00000000afa46c81 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000014a13ac8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5907: #0: 00000000173eae26 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000ecd60aae (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5908: #0: 000000001f277050 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000d7600b7e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5909: syz-executor0(22589): getblk(): executed=9 bh_count=0 bh_state=0 #0: 000000001bd82f65 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000088bdec2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5910: #0: 00000000099b603c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000088fc93ea (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5911: #0: 00000000acc34b4f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000cdf2e936 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5912: #0: 00000000be21eae7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000142c5120 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 3 locks held by syz-executor0/22589: 2 locks held by syz-executor0/22599: #0: 0000000028a43425 (sb_writers#13){.+.+}, at: sb_start_write include/linux/fs.h:1607 [inline] #0: 0000000028a43425 (sb_writers#13){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:359 #1: 0000000071dcf672 (&sb->s_type->i_mutex_key#23){++++}, at: inode_lock_shared include/linux/fs.h:774 [inline] #1: 0000000071dcf672 (&sb->s_type->i_mutex_key#23){++++}, at: do_last fs/namei.c:3323 [inline] #1: 0000000071dcf672 (&sb->s_type->i_mutex_key#23){++++}, at: path_openat+0x2444/0x5150 fs/namei.c:3534 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1010 Comm: khungtaskd Not tainted 4.20.0-rc1-next-20181109+ #110 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 nmi_trigger_cpumask_backtrace+0x1e8/0x22a 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:205 [inline] watchdog+0xb4c/0x1060 kernel/hung_task.c:289 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 22589 Comm: syz-executor0 Not tainted 4.20.0-rc1-next-20181109+ #110 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__find_get_block+0x6e/0xf10 fs/buffer.c:1320 Code: fe ff ff 48 c7 85 b8 fe ff ff b3 8a b5 41 48 c7 85 c0 fe ff ff 20 db 0f 89 48 c7 85 c8 fe ff ff e0 c6 e1 81 c7 00 f1 f1 f1 f1 40 04 04 f2 f2 f2 c7 40 08 f2 f2 f2 f2 c7 40 0c 00 f2 f2 f2 c7 RSP: 0018:ffff8801c3e9ec38 EFLAGS: 00000286 RAX: ffffed00387d3d90 RBX: dffffc0000000000 RCX: ffffc90005dcd000 RDX: 0000000000000200 RSI: 0000000000000004 RDI: ffff8801c051c680 RBP: ffff8801c3e9edc8 R08: ffff880178a8c600 R09: fffff94000e01eb6 R10: fffff94000e01eb6 R11: ffffea000700f5b7 R12: 0000000000000001 R13: 0000000000000200 R14: dffffc0000000000 R15: 1ffff100387d3ddd FS: 00007f1a1815b700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 000000017a82a000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __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+0x2464/0x5150 fs/namei.c:3534 do_filp_open+0x255/0x380 fs/namei.c:3564 do_sys_open+0x568/0x700 fs/open.c:1063 __do_sys_openat fs/open.c:1090 [inline] __se_sys_openat fs/open.c:1084 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1084 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:00007f1a1815ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569 RDX: 0000000000000002 RSI: 0000000020000080 RDI: 0000000000000004 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1a1815b6d4 R13: 00000000004c2e2f R14: 00000000004d4d98 R15: 00000000ffffffff