syz-executor2(16552): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor2(16552): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor2(16552): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor2(16552): getblk(): executed=9 bh_count=0 bh_state=0 syz-executor2(16552): getblk(): executed=9 bh_count=0 bh_state=0 INFO: task syz-executor2:16554 blocked for more than 140 seconds. Not tainted 4.19.0-rc8-next-20181019+ #98 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D22776 16554 5659 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3480 schedule+0xfe/0x460 kernel/sched/core.c:3524 __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:00007fa5c7a8ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569 RDX: 0000000000002761 RSI: 0000000020000200 RDI: ffffffffffffffff RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa5c7a8f6d4 R13: 00000000004c2b12 R14: 00000000004d4140 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/982: #0: 000000009e6c2621 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 1 lock held by rsyslogd/5499: #0: 0000000063c97a93 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5589: #0: 0000000007bf9e87 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000a67f1fbb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5590: #0: 000000006cd73abe (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000bd71ab6e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5591: #0: 000000004fb4a6e0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000035e5bb98 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5592: #0: 00000000c0057656 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000005d8c6451 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5593: #0: 000000007baf813f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000001a082966 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5594: #0: 00000000994eb96c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000048f44324 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5595: #0: 00000000ac7b369e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000008f7faffe (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 1 lock held by syz-executor2/5659: #0: 00000000ce473cb6 (&sb->s_type->i_mutex_key#26){++++}, at: inode_lock_shared include/linux/fs.h:779 [inline] #0: 00000000ce473cb6 (&sb->s_type->i_mutex_key#26){++++}, at: lookup_slow+0x49/0x80 fs/namei.c:1687 3 locks held by syz-executor2/16552: 2 locks held by syz-executor2/16554: #0: 00000000f8033f30 (sb_writers#22){.+.+}, at: sb_start_write include/linux/fs.h:1602 [inline] #0: 00000000f8033f30 (sb_writers#22){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:359 #1: 00000000ce473cb6 (&sb->s_type->i_mutex_key#26){++++}, at: inode_lock include/linux/fs.h:764 [inline] #1: 00000000ce473cb6 (&sb->s_type->i_mutex_key#26){++++}, at: do_last fs/namei.c:3321 [inline] #1: 00000000ce473cb6 (&sb->s_type->i_mutex_key#26){++++}, at: path_openat+0x15c4/0x5150 fs/namei.c:3534 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 982 Comm: khungtaskd Not tainted 4.19.0-rc8-next-20181019+ #98 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:204 [inline] watchdog+0xb39/0x1050 kernel/hung_task.c:265 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.098 msecs NMI backtrace for cpu 0 CPU: 0 PID: 16552 Comm: syz-executor2 Not tainted 4.19.0-rc8-next-20181019+ #98 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:look_up_lock_class kernel/locking/lockdep.c:692 [inline] RIP: 0010:match_held_lock+0x2d2/0x8d0 kernel/locking/lockdep.c:3409 Code: ef 03 80 3c 0f 00 0f 85 d3 05 00 00 48 c1 e8 03 4d 85 ff 4d 89 7e 80 4d 89 fc 48 b9 00 00 00 00 00 fc ff df c6 04 08 f8 75 4a <31> c0 48 ba 00 00 00 00 00 fc ff df 48 01 d3 48 c7 03 00 00 00 00 RSP: 0018:ffff8801870fe270 EFLAGS: 00000046 RAX: 0000000000000003 RBX: 1ffff10030e1fc53 RCX: ffffc90005e7a000 RDX: 0000000000000000 RSI: ffff8801c52a7978 RDI: ffff8801807049e2 RBP: ffff8801870fe360 R08: ffff880180704140 R09: ffffed003b5c5b4f R10: ffffed003b5c5b4f R11: ffff8801dae2da7b R12: ffff880180704140 R13: ffff8801807049c0 R14: ffff8801870fe338 R15: 0000000000000000 FS: 00007fa5c7ab0700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001be667000 CR4: 00000000001406f0 DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __lock_is_held+0xb5/0x140 kernel/locking/lockdep.c:3664 lock_is_held_type+0x118/0x210 kernel/locking/lockdep.c:3882 lock_is_held include/linux/lockdep.h:339 [inline] xa_head include/linux/xarray.h:539 [inline] xas_start+0x2d0/0x740 lib/xarray.c:182 xas_load+0x21/0x1e0 lib/xarray.c:227 find_get_entry+0x3ca/0x1120 mm/filemap.c:1415 pagecache_get_page+0x12f/0xf00 mm/filemap.c:1518 find_get_page_flags include/linux/pagemap.h:278 [inline] __find_get_block_slow fs/buffer.c:205 [inline] __find_get_block+0x635/0xf10 fs/buffer.c:1325 __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:00007fa5c7aafc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569 RDX: 0000000000002761 RSI: 0000000020000200 RDI: ffffffffffffffff RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa5c7ab06d4 R13: 00000000004c2b12 R14: 00000000004d4140 R15: 00000000ffffffff