INFO: task syz-executor0:22858 blocked for more than 140 seconds. Not tainted 5.0.0-rc1+ #18 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D21832 22858 8488 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_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:757 [inline] do_last fs/namei.c:3321 [inline] path_openat+0x1967/0x5650 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: Bad RIP value. RSP: 002b:00007f77a5970c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457ec9 RDX: 0000000000002761 RSI: 0000000020000180 RDI: ffffffffffffffff RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f77a59716d4 R13: 00000000004c3e63 R14: 00000000004d6ec8 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1040: #0: 00000000de65770f (rcu_read_lock){....}, at: debug_show_all_locks+0xc6/0x41d kernel/locking/lockdep.c:4389 1 lock held by rsyslogd/8327: #0: 00000000ffc0a933 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1b3/0x1f0 fs/file.c:795 2 locks held by getty/8449: #0: 00000000b0121902 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000048addd9e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8450: #0: 00000000336af1e9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000091c72f29 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8451: #0: 00000000e1d41778 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000056b1ad1a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8452: #0: 0000000087ddd0af (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000009532d540 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8453: #0: 0000000044c14f63 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000bf27fc1f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8454: #0: 000000008ce2048a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000efa0fb96 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8455: #0: 0000000088aeb162 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000009992ceee (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 3 locks held by syz-executor0/22854: 2 locks held by syz-executor0/22858: #0: 000000005ae28348 (sb_writers#13){.+.+}, at: sb_start_write include/linux/fs.h:1602 [inline] #0: 000000005ae28348 (sb_writers#13){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:357 #1: 000000009fb707fc (&sb->s_type->i_mutex_key#22){++++}, at: inode_lock include/linux/fs.h:757 [inline] #1: 000000009fb707fc (&sb->s_type->i_mutex_key#22){++++}, at: do_last fs/namei.c:3321 [inline] #1: 000000009fb707fc (&sb->s_type->i_mutex_key#22){++++}, at: path_openat+0x1967/0x5650 fs/namei.c:3534 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1040 Comm: khungtaskd Not tainted 5.0.0-rc1+ #18 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: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.370 msecs NMI backtrace for cpu 1 CPU: 1 PID: 22854 Comm: syz-executor0 Not tainted 5.0.0-rc1+ #18 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:find_held_lock+0xf3/0x120 kernel/locking/lockdep.c:3466 Code: 00 00 00 00 fc ff df 48 8b 55 d0 48 c1 ea 03 0f b6 04 02 84 c0 74 04 3c 03 7e 19 48 8b 45 d0 44 89 38 48 83 c4 08 4c 89 e0 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 48 8b 7d d0 e8 8a 87 62 00 eb dc e8 RSP: 0018:ffff888049f36b58 EFLAGS: 00000096 RAX: ffff88809946ac38 RBX: 1ffff110093e6d78 RCX: dffffc0000000000 RDX: 1ffff110093e6d7e RSI: 0000000000000000 RDI: ffff88809946ac48 RBP: ffff888049f36b78 R08: ffff88809946a340 R09: 0000000000000004 R10: 0000000000000000 R11: ffff8880ae72dc7b R12: ffff88809946ac38 R13: ffffffff81a08e15 R14: ffffffff899a3c40 R15: 0000000000000003 FS: 00007f77a5992700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000457e9f CR3: 00000000897ec000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_release kernel/locking/lockdep.c:3599 [inline] lock_release+0x28a/0xc40 kernel/locking/lockdep.c:3860 rcu_lock_release include/linux/rcupdate.h:228 [inline] rcu_read_unlock include/linux/rcupdate.h:661 [inline] find_get_entry+0x99c/0x10a0 mm/filemap.c:1506 pagecache_get_page+0xe6/0x1020 mm/filemap.c:1579 find_or_create_page include/linux/pagemap.h:322 [inline] grow_dev_page fs/buffer.c:947 [inline] grow_buffers fs/buffer.c:1016 [inline] __getblk_slow fs/buffer.c:1043 [inline] __getblk_gfp+0x38a/0xd20 fs/buffer.c:1320 __bread_gfp+0x2f/0x300 fs/buffer.c:1354 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+0x1983/0x5650 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:00007f77a5991c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457ec9 RDX: 0000000000002761 RSI: 0000000020000180 RDI: ffffffffffffffff RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f77a59926d4 R13: 00000000004c3e63 R14: 00000000004d6ec8 R15: 00000000ffffffff