INFO: task syz-executor0:7966 blocked for more than 140 seconds. Not tainted 5.0.0-rc1-next-20190111 #10 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D20104 7966 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2834 [inline] __schedule+0x897/0x1e60 kernel/sched/core.c:3475 schedule+0xfe/0x350 kernel/sched/core.c:3519 __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] lookup_slow+0x4a/0x80 fs/namei.c:1687 walk_component+0x8e5/0x26a0 fs/namei.c:1810 link_path_walk.part.0+0xa57/0x1550 fs/namei.c:2141 link_path_walk fs/namei.c:2072 [inline] path_openat+0x222/0x5660 fs/namei.c:3533 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: 0033:0x455ef0 Code: 48 48 8d 58 18 48 89 5c 24 40 48 8d 70 58 48 89 74 24 38 4c 8d 40 60 4c 89 44 24 30 85 c9 0f 85 3b 03 00 00 48 c7 40 20 00 00 <00> 00 48 c7 40 18 00 00 00 00 48 c7 40 58 00 00 00 00 48 c7 40 60 RSP: 002b:00007ffc8d1ebba0 EFLAGS: 00000206 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000455ef0 RDX: 0000000000000000 RSI: 0000000000090800 RDI: 00000000004bc9af RBP: 00000000000001cd R08: 0000000000000001 R09: 0000000001d67940 R10: 0000000000000000 R11: 0000000000000206 R12: 000000000000000e R13: 0000000000053aa7 R14: 000000000000007b R15: 0000000000000000 INFO: task syz-executor0:11544 blocked for more than 140 seconds. Not tainted 5.0.0-rc1-next-20190111 #10 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D27144 11544 7966 0x00000004 Call Trace: context_switch kernel/sched/core.c:2834 [inline] __schedule+0x897/0x1e60 kernel/sched/core.c:3475 schedule+0xfe/0x350 kernel/sched/core.c:3519 __rwsem_down_write_failed_common+0xa4d/0x1620 kernel/locking/rwsem-xadd.c:577 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:606 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 inode_lock include/linux/fs.h:766 [inline] do_last fs/namei.c:3321 [inline] path_openat+0x1967/0x5660 fs/namei.c:3534 do_filp_open+0x26f/0x370 fs/namei.c:3564 do_sys_open+0x59a/0x7c0 fs/open.c:1063 __do_sys_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+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: 28 c3 e8 aa 20 00 00 eb a8 cc cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 2e 48 83 ec 18 48 89 6c 24 10 48 <8d> 6c 24 10 48 8b 42 08 48 8b 4a 10 48 89 04 24 48 89 4c 24 08 e8 RSP: 002b:00007fee8ee8ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457ec9 RDX: 0000000000002761 RSI: 0000000020000200 RDI: ffffffffffffffff RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fee8ee8b6d4 R13: 00000000004c3e63 R14: 00000000004d6ec8 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1039: #0: 00000000a18de593 (rcu_read_lock){....}, at: debug_show_all_locks+0xc6/0x41d kernel/locking/lockdep.c:4408 1 lock held by rsyslogd/7840: 2 locks held by getty/7931: #0: 0000000058ea60e4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000001e6a9300 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7932: #0: 0000000079127453 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000051258eeb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7933: #0: 000000002c3db56d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000006575a57b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7934: #0: 00000000db3d83d9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000351047c4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7935: #0: 000000003fdbe00a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000002fc950be (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7936: #0: 000000003418fb6e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000609f73c9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7937: #0: 000000008cf46482 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000194f62b9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 1 lock held by syz-executor0/7966: #0: 000000005d99b887 (&sb->s_type->i_mutex_key#25){++++}, at: inode_lock_shared include/linux/fs.h:776 [inline] #0: 000000005d99b887 (&sb->s_type->i_mutex_key#25){++++}, at: lookup_slow+0x4a/0x80 fs/namei.c:1687 10 locks held by syz-executor0/11539: 2 locks held by syz-executor0/11544: #0: 00000000cabd6efb (sb_writers#16){.+.+}, at: sb_start_write include/linux/fs.h:1615 [inline] #0: 00000000cabd6efb (sb_writers#16){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:358 #1: 000000005d99b887 (&sb->s_type->i_mutex_key#25){++++}, at: inode_lock include/linux/fs.h:766 [inline] #1: 000000005d99b887 (&sb->s_type->i_mutex_key#25){++++}, at: do_last fs/namei.c:3321 [inline] #1: 000000005d99b887 (&sb->s_type->i_mutex_key#25){++++}, at: path_openat+0x1967/0x5660 fs/namei.c:3534 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1039 Comm: khungtaskd Not tainted 5.0.0-rc1-next-20190111 #10 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:247 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: 11539 Comm: syz-executor0 Not tainted 5.0.0-rc1-next-20190111 #10 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:450 Code: e9 00 00 00 49 8d 7c 24 38 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 17 41 03 5c 24 38 89 da ec <5b> 0f b6 c0 41 5c 5d c3 e8 08 ea e2 fd eb c2 e8 61 ea e2 fd eb e2 RSP: 0018:ffff8880a85fe9f0 EFLAGS: 00000002 RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: ffffffff83e394d1 RDI: ffffffff8bf7cbf8 RBP: ffff8880a85fea00 R08: ffff88809763e600 R09: ffffed10150bfd45 R10: ffffed10150bfd44 R11: 0000000000000003 R12: ffffffff8bf7cbc0 R13: 0000000000000020 R14: 0000000000000000 R15: fffffbfff17ef981 FS: 00007fee8eecd700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000023d9060 CR3: 0000000093652000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_in drivers/tty/serial/8250/8250.h:111 [inline] wait_for_xmitr+0xa7/0x250 drivers/tty/serial/8250/8250_port.c:2028 serial8250_console_putchar+0x20/0x60 drivers/tty/serial/8250/8250_port.c:3199 uart_console_write+0x57/0x120 drivers/tty/serial/serial_core.c:1907 serial8250_console_write+0x6d5/0xab0 drivers/tty/serial/8250/8250_port.c:3263 univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:586 call_console_drivers kernel/printk/printk.c:1784 [inline] console_unlock+0xc9a/0x1040 kernel/printk/printk.c:2455 vprintk_emit+0x370/0x960 kernel/printk/printk.c:1978 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:231 [inline] __find_get_block fs/buffer.c:1331 [inline] __find_get_block.cold+0x36/0xfb fs/buffer.c:1325 __getblk_slow fs/buffer.c:1058 [inline] __getblk_gfp+0x3c2/0x1140 fs/buffer.c:1357 __bread_gfp+0x2f/0x300 fs/buffer.c:1391 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_open+0x726/0x1b80 fs/namei.c:3213 do_last fs/namei.c:3324 [inline] path_openat+0x1983/0x5660 fs/namei.c:3534 do_filp_open+0x26f/0x370 fs/namei.c:3564 do_sys_open+0x59a/0x7c0 fs/open.c:1063 __do_sys_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+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:00007fee8eeccc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457ec9 RDX: 0000000000002761 RSI: 0000000020000200 RDI: ffffffffffffffff RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fee8eecd6d4 R13: 00000000004c3e63 R14: 00000000004d6ec8 R15: 00000000ffffffff