INFO: task syz-executor0:6458 blocked for more than 140 seconds. Not tainted 5.0.0-rc2-next-20190117 #14 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D27096 6458 13225 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] 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_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: 0033:0x458099 Code: Bad RIP value. RSP: 002b:00007fbd27fd2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458099 RDX: 0000000000000002 RSI: 0000000020000040 RDI: ffffffffffffffff RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbd27fd36d4 R13: 00000000004c4069 R14: 00000000004d7270 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1040: #0: 000000005c6b06ff (rcu_read_lock){....}, at: debug_show_all_locks+0xc6/0x41d kernel/locking/lockdep.c:4408 1 lock held by rsyslogd/7945: #0: 00000000703920b7 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1b3/0x1f0 fs/file.c:796 2 locks held by getty/8035: #0: 000000006afdd6ee (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000440a77be (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8036: #0: 00000000c2917821 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e15b7235 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8037: #0: 00000000391a187f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008a0bd668 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8038: #0: 000000008d520d5d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000009821b5cb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8039: #0: 00000000660fb573 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000eb31e152 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8040: #0: 000000001edbc49a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000ba3b2c6d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/8041: #0: 000000001ddf2032 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000d8e56775 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 1 lock held by syz-executor3/27680: #0: 00000000a5a74b0a (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1407 [inline] #0: 00000000a5a74b0a (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file.isra.0+0x45d/0x2700 fs/exec.c:1750 1 lock held by syz-executor3/27733: #0: 00000000558fc090 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1407 [inline] #0: 00000000558fc090 (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file.isra.0+0x45d/0x2700 fs/exec.c:1750 3 locks held by syz-executor0/6448: 2 locks held by syz-executor0/6458: #0: 000000001c2d1a81 (sb_writers#23){.+.+}, at: sb_start_write include/linux/fs.h:1615 [inline] #0: 000000001c2d1a81 (sb_writers#23){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:358 #1: 00000000ff75c3bd (&sb->s_type->i_mutex_key#28){++++}, at: inode_lock_shared include/linux/fs.h:776 [inline] #1: 00000000ff75c3bd (&sb->s_type->i_mutex_key#28){++++}, at: do_last fs/namei.c:3323 [inline] #1: 00000000ff75c3bd (&sb->s_type->i_mutex_key#28){++++}, at: path_openat+0x25da/0x5660 fs/namei.c:3534 2 locks held by syz-executor0/6461: #0: 000000001c2d1a81 (sb_writers#23){.+.+}, at: sb_start_write include/linux/fs.h:1615 [inline] #0: 000000001c2d1a81 (sb_writers#23){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:358 #1: 00000000ff75c3bd (&sb->s_type->i_mutex_key#28){++++}, at: inode_lock include/linux/fs.h:766 [inline] #1: 00000000ff75c3bd (&sb->s_type->i_mutex_key#28){++++}, at: do_last fs/namei.c:3321 [inline] #1: 00000000ff75c3bd (&sb->s_type->i_mutex_key#28){++++}, at: path_openat+0x1967/0x5660 fs/namei.c:3534 2 locks held by syz-executor0/6494: #0: 000000001c2d1a81 (sb_writers#23){.+.+}, at: sb_start_write include/linux/fs.h:1615 [inline] #0: 000000001c2d1a81 (sb_writers#23){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:358 #1: 00000000ff75c3bd (&sb->s_type->i_mutex_key#28){++++}, at: inode_lock_shared include/linux/fs.h:776 [inline] #1: 00000000ff75c3bd (&sb->s_type->i_mutex_key#28){++++}, at: do_last fs/namei.c:3323 [inline] #1: 00000000ff75c3bd (&sb->s_type->i_mutex_key#28){++++}, at: path_openat+0x25da/0x5660 fs/namei.c:3534 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1040 Comm: khungtaskd Not tainted 5.0.0-rc2-next-20190117 #14 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6448 Comm: syz-executor0 Not tainted 5.0.0-rc2-next-20190117 #14 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:match_held_lock+0x7d/0x780 kernel/locking/lockdep.c:3399 Code: 85 68 ff ff ff d0 88 63 81 c7 00 f1 f1 f1 f1 c7 40 04 00 f2 f2 f2 c7 40 08 00 f3 f3 f3 65 48 8b 04 25 28 00 00 00 48 89 45 d0 <31> c0 48 89 f8 48 c1 e8 03 80 3c 08 00 0f 85 8b 04 00 00 49 39 75 RSP: 0018:ffff8881d42568a0 EFLAGS: 00000086 RAX: 57d3d3d109458200 RBX: ffff88808ee343c0 RCX: dffffc0000000000 RDX: 1ffff1103a84ad18 RSI: ffffffff899a4600 RDI: ffff88808ee34c78 RBP: ffff8881d4256968 R08: ffff88808ee343c0 R09: ffffed1015ce5b90 R10: ffffed1015ce5b8f R11: ffff8880ae72dc7b R12: 1ffff1103a84ad18 R13: ffff88808ee34c68 R14: ffff8881d4256940 R15: ffff88808ee34c68 FS: 00007fbd27ff4700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000045806f CR3: 0000000091fcb000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_is_held+0xb6/0x140 kernel/locking/lockdep.c:3680 lock_is_held_type+0x110/0x210 kernel/locking/lockdep.c:3898 lock_is_held include/linux/lockdep.h:337 [inline] rcu_read_lock_held kernel/rcu/update.c:281 [inline] rcu_read_lock_held+0xa3/0xd0 kernel/rcu/update.c:273 xa_entry include/linux/xarray.h:1004 [inline] xas_descend+0x404/0x500 lib/xarray.c:198 xas_load+0xef/0x150 lib/xarray.c:234 find_get_entry+0x353/0x1090 mm/filemap.c:1476 pagecache_get_page+0xe5/0x1070 mm/filemap.c:1582 find_get_page_flags include/linux/pagemap.h:279 [inline] __find_get_block_slow fs/buffer.c:205 [inline] __find_get_block fs/buffer.c:1331 [inline] __find_get_block+0x615/0xf20 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: 0033:0x458099 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:00007fbd27ff3c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458099 RDX: 0000000000002761 RSI: 0000000020000040 RDI: ffffffffffffffff RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbd27ff46d4 R13: 00000000004c408f R14: 00000000004d72a0 R15: 00000000ffffffff