syz-executor0(9722): getblk(): executed=9 bh_count=0 bh_state=0 kworker/u4:7(24916): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor0(30085): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor0(9722): getblk(): executed=9 bh_count=0 bh_state=0 kworker/u4:7(24916): getblk(): executed=9 bh_count=0 bh_state=0 INFO: task syz-executor0:30094 blocked for more than 140 seconds. Not tainted 4.19.0-rc1-next-20180831+ #53 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D23416 30094 9722 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x87c/0x1df0 kernel/sched/core.c:3473 schedule+0xfb/0x450 kernel/sched/core.c:3517 __rwsem_down_write_failed_common+0x98b/0x1650 kernel/locking/rwsem-xadd.c:566 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:595 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+0xaa/0x130 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:746 [inline] do_truncate+0x19f/0x2b0 fs/open.c:61 handle_truncate fs/namei.c:3008 [inline] do_last fs/namei.c:3424 [inline] path_openat+0x34e3/0x5340 fs/namei.c:3534 do_filp_open+0x255/0x380 fs/namei.c:3564 do_sys_open+0x584/0x720 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: 0033:0x457099 Code: 48 8b 54 24 38 48 8b 7c 24 48 eb 8d 48 8b 6c 24 50 48 83 c4 58 c3 48 89 04 24 48 89 5c 24 08 e8 0d a9 fb ff 48 8b 44 24 40 48 <8b> 4c 24 48 48 8b 54 24 38 4c 8b 54 24 18 e9 ee fe ff ff 48 89 74 RSP: 002b:00007fe1dc301c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fe1dc3026d4 RCX: 0000000000457099 RDX: 0000000000002761 RSI: 00000000200000c0 RDI: ffffffffffffffff RBP: 0000000000930140 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d3318 R14: 00000000004c819c R15: 0000000000000001 INFO: task syz-executor0:30165 blocked for more than 140 seconds. Not tainted 4.19.0-rc1-next-20180831+ #53 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D26472 30165 9722 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x87c/0x1df0 kernel/sched/core.c:3473 schedule+0xfb/0x450 kernel/sched/core.c:3517 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3575 __mutex_lock_common kernel/locking/mutex.c:1003 [inline] __mutex_lock+0xbf9/0x1700 kernel/locking/mutex.c:1073 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 __fdget_pos+0x1bb/0x200 fs/file.c:766 fdget_pos include/linux/file.h:70 [inline] ksys_write+0x7f/0x260 fs/read_write.c:593 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457099 Code: 48 8b 54 24 38 48 8b 7c 24 48 eb 8d 48 8b 6c 24 50 48 83 c4 58 c3 48 89 04 24 48 89 5c 24 08 e8 0d a9 fb ff 48 8b 44 24 40 48 <8b> 4c 24 48 48 8b 54 24 38 4c 8b 54 24 18 e9 ee fe ff ff 48 89 74 RSP: 002b:00007fe1dc2bfc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe1dc2c06d4 RCX: 0000000000457099 RDX: 00000000000297ef RSI: 0000000020000080 RDI: 0000000000000005 RBP: 0000000000930280 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d7ec0 R14: 00000000004cab41 R15: 0000000000000003 Showing all locks held in the system: 1 lock held by khungtaskd/793: #0: 00000000473c4417 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4436 1 lock held by rsyslogd/4549: 2 locks held by getty/4640: #0: 00000000bda57991 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000971acbe0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4641: #0: 000000004180f002 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000001b96ede2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4642: #0: 000000003e2f4c0d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000008b3b063e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4643: #0: 0000000050e1506e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000022945e5a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4644: #0: 0000000028f17f82 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000008b4e2e5c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4645: #0: 00000000c7177350 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000888d7b23 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4646: #0: 00000000850333f2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000005dc86f5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-executor0/9722: 3 locks held by kworker/u4:7/24916: 4 locks held by syz-executor0/30085: 2 locks held by syz-executor0/30094: #0: 00000000f3e2a501 (sb_writers#21){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline] #0: 00000000f3e2a501 (sb_writers#21){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 00000000ac0b37ba (&sb->s_type->i_mutex_key#29){++++}, at: inode_lock include/linux/fs.h:746 [inline] #1: 00000000ac0b37ba (&sb->s_type->i_mutex_key#29){++++}, at: do_truncate+0x19f/0x2b0 fs/open.c:61 1 lock held by syz-executor0/30165: #0: 000000004c1955b5 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 793 Comm: khungtaskd Not tainted 4.19.0-rc1-next-20180831+ #53 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 nmi_cpu_backtrace.cold.3+0x48/0x88 lib/nmi_backtrace.c:101 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 trigger_all_cpu_backtrace include/linux/nmi.h:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb39/0x1040 kernel/hung_task.c:265 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 syz-executor0(30085): getblk(): executed=9 bh_count=0 bh_state=0 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.780 msecs CPU: 1 PID: 24916 Comm: kworker/u4:7 Not tainted 4.19.0-rc1-next-20180831+ #53 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:lookup_bh_lru fs/buffer.c:1295 [inline] RIP: 0010:__find_get_block+0x1a4/0xdf0 fs/buffer.c:1322 Code: 20 93 02 00 65 4a 8b 1c f0 48 89 9d 90 fe ff ff 48 85 db 74 c0 e8 fc cb a4 ff 48 8d 7b 18 48 89 f8 48 c1 e8 03 42 80 3c 28 00 <0f> 85 8f 0a 00 00 4c 8b 7b 18 48 8b bd b0 fe ff ff 4c 89 fe e8 83 RSP: 0018:ffff880187d7e228 EFLAGS: 00000046 RAX: 1ffff1003037682d RBX: ffff880181bb4150 RCX: ffffffff81d7fbc5 RDX: 0000000000000000 RSI: ffffffff81d7fbf4 RDI: ffff880181bb4168 RBP: ffff880187d7e3b8 R08: ffff88018d138280 R09: fffff94000d059b6 R10: fffff94000d059b6 R11: ffffea000682cdb7 R12: 000000000000000b R13: dffffc0000000000 R14: 000000000000000b R15: 0000000000031393 FS: 0000000000000000(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001bdb77000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __getblk_slow fs/buffer.c:1059 [inline] __getblk_gfp+0x3dc/0xe00 fs/buffer.c:1352 __bread_gfp+0x2d/0x310 fs/buffer.c:1386 sb_bread include/linux/buffer_head.h:307 [inline] __fat_write_inode+0x347/0xb60 fs/fat/inode.c:860 fat_write_inode+0x97/0x180 fs/fat/inode.c:909 write_inode fs/fs-writeback.c:1183 [inline] __writeback_single_inode+0xd8e/0x1330 fs/fs-writeback.c:1382 writeback_sb_inodes+0x71f/0x1150 fs/fs-writeback.c:1587 __writeback_inodes_wb+0x1b8/0x340 fs/fs-writeback.c:1656 wb_writeback+0x989/0xe80 fs/fs-writeback.c:1765 wb_check_old_data_flush fs/fs-writeback.c:1867 [inline] wb_do_writeback fs/fs-writeback.c:1920 [inline] wb_workfn+0xee6/0x1610 fs/fs-writeback.c:1949 process_one_work+0xc73/0x1aa0 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:415