syz-executor0(12414): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor0(12414): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor0(12414): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor0(12414): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor0(12414): getblk(): executed=9 bh_count=0 bh_state=0 INFO: task syz-executor0:12457 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 D24704 12457 8051 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 syz-executor0(12414): getblk(): executed=9 bh_count=0 bh_state=0 schedule+0xef/0x370 kernel/sched/core.c:3516 __rwsem_down_write_failed_common+0xc9a/0x15e0 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:764 [inline] do_last fs/namei.c:3321 [inline] path_openat+0x15c4/0x5150 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:00007f7a690a4c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569 RDX: 0000000000002761 RSI: 0000000020000180 RDI: ffffffffffffffff RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7a690a56d4 R13: 00000000004c2d83 R14: 00000000004d4728 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1010: #0: 00000000c7c8680d (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 1 lock held by rsyslogd/5871: #0: 00000000a9f0d66b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5962: #0: 000000004897e2e3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000009660814 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5963: #0: 000000007519d809 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000b56c4486 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5964: #0: 00000000031ebd46 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000007b4453d2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5965: #0: 00000000a45f9a8a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000c208b284 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5966: #0: 00000000a0f34415 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000006caa92ee (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5967: #0: 0000000026f01f16 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000009037cf8b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5968: #0: 0000000092a702ea (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000077dfdd21 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 4 locks held by syz-executor0/12414: 2 locks held by syz-executor0/12457: #0: 000000002ed2dc3c (sb_writers#12){.+.+}, at: sb_start_write include/linux/fs.h:1607 [inline] #0: 000000002ed2dc3c (sb_writers#12){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:359 #1: 00000000d4281235 (&sb->s_type->i_mutex_key#20){++++}, at: inode_lock include/linux/fs.h:764 [inline] #1: 00000000d4281235 (&sb->s_type->i_mutex_key#20){++++}, at: do_last fs/namei.c:3321 [inline] #1: 00000000d4281235 (&sb->s_type->i_mutex_key#20){++++}, at: path_openat+0x15c4/0x5150 fs/namei.c:3534 ============================================= NMI backtrace for cpu 0 CPU: 0 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 0 to CPUs 1: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.402 msecs NMI backtrace for cpu 1 CPU: 1 PID: 12414 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:arch_local_save_flags arch/x86/include/asm/paravirt.h:756 [inline] RIP: 0010:check_preemption_disabled+0x95/0x280 lib/smp_processor_id.c:18 Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 42 01 00 00 48 83 3d ff f4 bf 05 00 0f 84 2d 01 00 00 e8 fc a1 ed fd 9c <58> 0f 1f 44 00 00 25 00 02 00 00 31 ff 48 89 c3 48 89 c6 e8 13 a3 RSP: 0018:ffff8801b3296bd8 EFLAGS: 00000046 RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc90005a47000 RDX: 0000000000040000 RSI: ffffffff839206b4 RDI: ffffffff8951fba8 RBP: ffff8801b3296c10 R08: ffff8801819d6340 R09: fffff94000e13fe6 R10: fffff94000e13fe6 R11: ffffea000709ff37 R12: 0000000000000001 R13: ffffffff8860fe60 R14: ffffffff8835cec0 R15: 0000000000000447 FS: 00007f7a690e7700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001cdf43000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __this_cpu_preempt_check+0x1c/0x20 lib/smp_processor_id.c:62 lookup_bh_lru fs/buffer.c:1292 [inline] __find_get_block+0x183/0xf10 fs/buffer.c:1321 __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 __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:00007f7a690e6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569 RDX: 0000000000002761 RSI: 0000000020000180 RDI: ffffffffffffffff RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7a690e76d4 R13: 00000000004c2d83 R14: 00000000004d4728 R15: 00000000ffffffff