INFO: task syz-executor0:8755 blocked for more than 140 seconds. Not tainted 4.20.0-next-20190103 #5 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D24680 8755 8100 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x897/0x1e60 kernel/sched/core.c:3472 schedule+0xfe/0x350 kernel/sched/core.c:3516 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:280 [inline] rwsem_down_read_failed+0x360/0x6d0 kernel/locking/rwsem-xadd.c:297 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x9b/0x120 kernel/locking/rwsem.c:26 inode_lock_shared include/linux/fs.h:776 [inline] do_last fs/namei.c:3323 [inline] path_openat+0x25da/0x5660 fs/namei.c:3534 do_filp_open+0x26f/0x370 fs/namei.c:3564 do_sys_open+0x59a/0x7c0 fs/open.c:1063 __do_sys_open fs/open.c:1081 [inline] __se_sys_open fs/open.c:1076 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1076 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: Bad RIP value. RSP: 002b:00007f4b46828c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 0000000000000200 RDI: 0000000020000380 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4b468296d4 R13: 00000000004f471f R14: 00000000004d6d30 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1040: #0: 00000000623f3e4a (rcu_read_lock){....}, at: debug_show_all_locks+0xc6/0x41d kernel/locking/lockdep.c:4389 1 lock held by rsyslogd/7954: 2 locks held by getty/8066: #0: 000000001422fa06 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000000ac28b0c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8067: #0: 00000000404da27b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a1329683 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8068: #0: 00000000ce4e8842 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000078d99a49 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8069: #0: 00000000ff5fdc33 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000024c37d30 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8070: #0: 000000005a9469b5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000014ca2cbf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8071: #0: 00000000f900a0e9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000037463df2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8072: #0: 00000000f0d59f38 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000001df427 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by syz-executor0/8755: #0: 00000000ff6ae6a7 (sb_writers#17){.+.+}, at: sb_start_write include/linux/fs.h:1615 [inline] #0: 00000000ff6ae6a7 (sb_writers#17){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:358 #1: 00000000a773b74c (&sb->s_type->i_mutex_key#26){++++}, at: inode_lock_shared include/linux/fs.h:776 [inline] #1: 00000000a773b74c (&sb->s_type->i_mutex_key#26){++++}, at: do_last fs/namei.c:3323 [inline] #1: 00000000a773b74c (&sb->s_type->i_mutex_key#26){++++}, at: path_openat+0x25da/0x5660 fs/namei.c:3534 7 locks held by syz-executor0/8761: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1040 Comm: khungtaskd Not tainted 4.20.0-next-20190103 #5 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+0x1db/0x2d0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 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:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0xbbb/0x1170 kernel/hung_task.c:287 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8761 Comm: syz-executor0 Not tainted 4.20.0-next-20190103 #5 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:mark_irqflags kernel/locking/lockdep.c:2940 [inline] RIP: 0010:__lock_acquire+0x1360/0x4a10 kernel/locking/lockdep.c:3295 Code: 44 8b 44 24 68 0f 85 60 f7 ff ff e9 d1 f5 ff ff 83 e1 0f 41 bb 01 00 00 00 83 c9 20 66 89 48 22 e9 bf f5 ff ff ba 04 00 00 00 <4c> 89 d6 4c 89 e7 44 89 44 24 68 4c 89 54 24 70 e8 bb ce ff ff 85 RSP: 0018:ffff8880ae707750 EFLAGS: 00000002 RAX: 000000000000000c RBX: 0000000000000020 RCX: 0000000000042000 RDX: 0000000000000004 RSI: 0000000000000001 RDI: ffff888088b3ce81 RBP: ffff8880ae7079e0 R08: 0000000000000004 R09: 0000000000000001 R10: ffff888088b3ce60 R11: ffff8880ae723bd8 R12: ffff888088b3c540 R13: ffff888088b3ce82 R14: 0000000000000001 R15: 0000000000000050 FS: 00007f4b46808700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000019b9bf0 CR3: 000000009838e000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1db/0x570 kernel/locking/lockdep.c:3841 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0x60/0x80 kernel/locking/spinlock.c:160 __run_timers+0x121/0xd50 kernel/time/timer.c:1657 run_timer_softirq+0x52/0xb0 kernel/time/timer.c:1694 __do_softirq+0x30b/0xb11 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x180/0x1d0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1b7/0x760 arch/x86/kernel/apic/apic.c:1062 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:766 [inline] RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1744 [inline] RIP: 0010:vprintk_emit+0x84c/0x960 kernel/printk/printk.c:1977 Code: 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 ef 00 00 00 48 83 3d 44 57 2a 08 00 74 2d e8 4d d8 19 00 48 8b bd 10 ff ff ff 57 9d <0f> 1f 44 00 00 e9 a3 fe ff ff e8 35 d8 19 00 0f 0b e8 2e d8 19 00 RSP: 0018:ffff88804c8af1f0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000040000 RBX: 1ffff11009915e44 RCX: ffffc90005fba000 RDX: 0000000000040000 RSI: ffffffff816828b3 RDI: 0000000000000246 RBP: ffff88804c8af2e8 R08: 0000000000000006 R09: ffff888088b3ce58 R10: ffff888088b3c540 R11: 0000000000000000 R12: 0000000000000200 R13: ffffed1009915e4e R14: 0000000000000000 R15: ffff88804c8af2c0 vprintk_default+0x28/0x30 kernel/printk/printk.c:2005 vprintk_func+0x7e/0x189 kernel/printk/printk_safe.c:398 printk+0xba/0xed kernel/printk/printk.c:2038 __find_get_block_slow fs/buffer.c:237 [inline] __find_get_block fs/buffer.c:1325 [inline] __find_get_block.cold+0xd4/0xfb fs/buffer.c:1319 __getblk_slow fs/buffer.c:1058 [inline] __getblk_gfp+0x3c5/0x1130 fs/buffer.c:1351 __bread_gfp+0x2f/0x300 fs/buffer.c:1385 sb_bread include/linux/buffer_head.h:307 [inline] fat__get_entry+0x586/0xa40 fs/fat/dir.c:101 fat_get_entry fs/fat/dir.c:129 [inline] fat_search_long+0x345/0x17d0 fs/fat/dir.c:479 vfat_find+0x10e/0x140 fs/fat/namei_vfat.c:697 vfat_lookup+0x10a/0x6b0 fs/fat/namei_vfat.c:711 __lookup_hash+0x122/0x190 fs/namei.c:1546 filename_create+0x1d6/0x5a0 fs/namei.c:3636 user_path_create fs/namei.c:3693 [inline] do_mknodat+0x1bd/0x530 fs/namei.c:3754 __do_sys_mknod fs/namei.c:3794 [inline] __se_sys_mknod fs/namei.c:3792 [inline] __x64_sys_mknod+0x7b/0xb0 fs/namei.c:3792 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: 6d b7 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f4b46807c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000085 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000440 RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4b468086d4 R13: 00000000004c3b27 R14: 00000000004d6880 R15: 00000000ffffffff