INFO: task syz-executor.1:29500 blocked for more than 140 seconds. Not tainted 4.14.169-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D30000 29500 7262 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 wb_wait_for_completion fs/fs-writeback.c:221 [inline] wb_wait_for_completion+0x133/0x190 fs/fs-writeback.c:217 sync_inodes_sb+0x170/0x9b0 fs/fs-writeback.c:2461 sync_inodes_one_sb+0x48/0x60 fs/sync.c:74 iterate_supers+0x130/0x250 fs/super.c:613 sys_sync+0x7a/0x130 fs/sync.c:113 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45b399 RSP: 002b:00007f41cba61c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f41cba626d4 RCX: 000000000045b399 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000b72 R14: 00000000004c953f R15: 000000000075bf2c INFO: task syz-executor.1:29534 blocked for more than 140 seconds. Not tainted 4.14.169-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D29120 29534 7262 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384 schedule+0x92/0x1c0 kernel/sched/core.c:3428 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline] rwsem_down_write_failed+0x5ce/0xb50 kernel/locking/rwsem-xadd.c:617 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:56 bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:336 [inline] sync_inodes_sb+0x150/0x9b0 fs/fs-writeback.c:2459 sync_inodes_one_sb+0x48/0x60 fs/sync.c:74 iterate_supers+0x130/0x250 fs/super.c:613 sys_sync+0x7a/0x130 fs/sync.c:113 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45b399 RSP: 002b:00007f41cba40c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f41cba416d4 RCX: 000000000045b399 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000b72 R14: 00000000004c953f R15: 000000000075bfd4 Showing all locks held in the system: 1 lock held by khungtaskd/1057: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544 1 lock held by rsyslogd/7093: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xab/0xd0 fs/file.c:769 2 locks held by getty/7215: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7216: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7217: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7218: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7219: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7220: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by getty/7221: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.2/11316: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.2/11494: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.2/11701: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.2/11773: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.2/11932: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.2/12060: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.2/12123: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.2/12194: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.2/12232: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.3/12307: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.2/12316: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.3/12363: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.2/12370: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.2/12426: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.3/12502: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.2/12513: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.3/12580: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.2/12592: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.3/12652: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.3/12724: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.2/12830: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.3/12911: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.4/12912: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.5/12925: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.2/12944: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&rq->lock){-.-.}, at: [] rq_lock kernel/sched/sched.h:1741 [inline] #1: (&rq->lock){-.-.}, at: [] __schedule+0x1da/0x1cd0 kernel/sched/core.c:3321 2 locks held by syz-executor.4/13028: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&rq->lock){-.-.}, at: [] rq_lock kernel/sched/sched.h:1741 [inline] #1: (&rq->lock){-.-.}, at: [] __schedule+0x1da/0x1cd0 kernel/sched/core.c:3321 2 locks held by syz-executor.2/13042: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.0/13115: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.4/13128: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.2/13138: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.5/13142: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.5/13238: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.2/13273: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.4/13280: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.0/13365: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.5/13382: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.4/13877: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.2/13928: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.3/14308: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.5/14337: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.0/14458: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.3/14489: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.4/14752: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.5/14952: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.0/15131: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.3/16091: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.3/16727: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 1 lock held by syz-executor.2/16774: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 1 lock held by syz-executor.3/16787: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 2 locks held by syz-executor.3/16844: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 2 locks held by syz-executor.5/16985: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_trylock include/linux/fs.h:738 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234 4 locks held by kworker/u4:0/11795: #0: ("writeback"){+.+.}, at: [] work_static include/linux/workqueue.h:199 [inline] #0: ("writeback"){+.+.}, at: [] set_work_data kernel/workqueue.c:619 [inline] #0: ("writeback"){+.+.}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ("writeback"){+.+.}, at: [] process_one_work+0x76e/0x1600 kernel/workqueue.c:2085 #1: ((&(&wb->dwork)->work)){+.+.}, at: [] process_one_work+0x7ab/0x1600 kernel/workqueue.c:2089 #2: (&type->s_umount_key#45){++++}, at: [] trylock_super+0x20/0xf0 fs/super.c:402 #3: (&sbi->s_journal_flag_rwsem){.+.+}, at: [] do_writepages+0xd0/0x250 mm/page-writeback.c:2361 2 locks held by syz-executor.1/29500: #0: (&type->s_umount_key#45){++++}, at: [] iterate_supers+0xe1/0x250 fs/super.c:611 #1: (&bdi->wb_switch_rwsem){+.+.}, at: [] bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:336 [inline] #1: (&bdi->wb_switch_rwsem){+.+.}, at: [] sync_inodes_sb+0x150/0x9b0 fs/fs-writeback.c:2459 2 locks held by syz-executor.1/29534: #0: (&type->s_umount_key#45){++++}, at: [] iterate_supers+0xe1/0x250 fs/super.c:611 #1: (&bdi->wb_switch_rwsem){+.+.}, at: [] bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:336 [inline] #1: (&bdi->wb_switch_rwsem){+.+.}, at: [] sync_inodes_sb+0x150/0x9b0 fs/fs-writeback.c:2459 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1057 Comm: khungtaskd Not tainted 4.14.169-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x142/0x197 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x141/0x189 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:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5e7/0xb90 kernel/hung_task.c:274 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 12370 Comm: syz-executor.2 Not tainted 4.14.169-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888055c5e340 task.stack: ffff88803ed68000 RIP: 0010:radix_tree_load_root lib/radix-tree.c:608 [inline] RIP: 0010:__radix_tree_lookup+0x86/0x2f0 lib/radix-tree.c:1040 RSP: 0018:ffff88803ed6f6e8 EFLAGS: 00000286 RAX: 0000000000000000 RBX: ffff88807f3ca401 RCX: ffff88803ed6f778 RDX: 0000000000000000 RSI: 000000000000017d RDI: ffff88809434fac0 RBP: ffff88803ed6f748 R08: 0000000000000000 R09: ffff888055c5ec08 R10: ffff888055c5ebe8 R11: ffff888055c5e340 R12: ffff88807f3ca400 R13: 000000000000017d R14: dffffc0000000000 R15: dffffc0000000000 FS: 00007fd618295700(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c428d5cb00 CR3: 0000000090f6a000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: radix_tree_lookup_slot+0x63/0xa0 lib/radix-tree.c:1079 find_get_entry+0x8c/0x680 mm/filemap.c:1355 pagecache_get_page+0x4a/0x9e0 mm/filemap.c:1465 find_get_page include/linux/pagemap.h:276 [inline] generic_file_buffered_read mm/filemap.c:1999 [inline] generic_file_read_iter+0x66a/0x28d0 mm/filemap.c:2273 ext4_file_read_iter+0x14e/0x340 fs/ext4/file.c:75 call_read_iter include/linux/fs.h:1771 [inline] generic_file_splice_read+0x37d/0x600 fs/splice.c:307 do_splice_to+0x105/0x170 fs/splice.c:880 splice_direct_to_actor+0x222/0x7b0 fs/splice.c:952 do_splice_direct+0x18d/0x230 fs/splice.c:1061 do_sendfile+0x4db/0xbd0 fs/read_write.c:1441 SYSC_sendfile64 fs/read_write.c:1496 [inline] SyS_sendfile64+0x9d/0x110 fs/read_write.c:1488 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45b399 RSP: 002b:00007fd618294c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fd6182956d4 RCX: 000000000045b399 RDX: 0000000020d83ff8 RSI: 0000000000000007 RDI: 0000000000000005 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 00008000fffffffb R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000008ca R14: 00000000004ca24d R15: 000000000075bf2c Code: 83 e0 03 48 83 f8 01 0f 85 d9 01 00 00 e8 f3 7e f9 fa 48 89 d8 48 89 da 49 89 dc 48 c1 e8 03 83 e2 06 49 83 e4 fe 42 0f b6 04 30 <38> d0 7f 08 84 c0 0f 85 28 02 00 00 41 0f b6 0c 24 41 bc 40 00