syzbot


INFO: task hung in sync_inodes_sb

Status: auto-closed as invalid on 2020/06/02 17:26
Reported-by: syzbot+af03214457b32b28a28b@syzkaller.appspotmail.com
First crash: 877d, last: 877d
similar bugs (8):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in sync_inodes_sb (2) 4 1164d 1182d 0/22 auto-closed as invalid on 2019/10/19 16:22
upstream INFO: task hung in sync_inodes_sb (3) C done 6 907d 916d 16/22 fixed on 2020/02/14 01:19
upstream INFO: task hung in sync_inodes_sb 58 1261d 1500d 0/22 closed as dup on 2018/09/08 15:37
android-49 INFO: task hung in sync_inodes_sb 11 1401d 1480d 0/3 auto-closed as invalid on 2019/02/24 06:19
android-49 INFO: task hung in sync_inodes_sb (2) 2 990d 1152d 0/3 auto-closed as invalid on 2020/02/10 00:14
upstream INFO: task hung in sync_inodes_sb (4) C done inconclusive 6 78d 585d 0/22 upstream: reported C repro on 2020/11/21 04:55
linux-4.14 INFO: task hung in sync_inodes_sb (2) C 6 12d 538d 0/1 upstream: reported C repro on 2021/01/07 19:48
linux-4.19 INFO: task hung in sync_inodes_sb C error 4 206d 628d 0/1 upstream: reported C repro on 2020/10/09 07:19

Sample crash report:
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: [<ffffffff81488cf8>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544
1 lock held by rsyslogd/7093:
 #0:  (&f->f_pos_lock){+.+.}, at: [<ffffffff8196346b>] __fdget_pos+0xab/0xd0 fs/file.c:769
2 locks held by getty/7215:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff86692003>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834c3816>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7216:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff86692003>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834c3816>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7217:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff86692003>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834c3816>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7218:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff86692003>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834c3816>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7219:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff86692003>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834c3816>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7220:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff86692003>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834c3816>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by getty/7221:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff86692003>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834c3816>] n_tty_read+0x1e6/0x17d0 drivers/tty/n_tty.c:2156
2 locks held by syz-executor.2/11316:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.2/11494:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.2/11701:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.2/11773:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.2/11932:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.2/12060:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.2/12123:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.2/12194:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.2/12232:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.3/12307:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.2/12316:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.3/12363:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.2/12370:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.2/12426:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.3/12502:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.2/12513:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.3/12580:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.2/12592:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.3/12652:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.3/12724:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.2/12830:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.3/12911:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.4/12912:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.5/12925:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.2/12944:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&rq->lock){-.-.}, at: [<ffffffff8668004a>] rq_lock kernel/sched/sched.h:1741 [inline]
 #1:  (&rq->lock){-.-.}, at: [<ffffffff8668004a>] __schedule+0x1da/0x1cd0 kernel/sched/core.c:3321
2 locks held by syz-executor.4/13028:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&rq->lock){-.-.}, at: [<ffffffff8668004a>] rq_lock kernel/sched/sched.h:1741 [inline]
 #1:  (&rq->lock){-.-.}, at: [<ffffffff8668004a>] __schedule+0x1da/0x1cd0 kernel/sched/core.c:3321
2 locks held by syz-executor.2/13042:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.0/13115:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.4/13128:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.2/13138:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.5/13142:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.5/13238:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.2/13273:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.4/13280:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.0/13365:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.5/13382:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.4/13877:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.2/13928:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.3/14308:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.5/14337:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.0/14458:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.3/14489:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.4/14752:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.5/14952:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.0/15131:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.3/16091:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.3/16727:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
1 lock held by syz-executor.2/16774:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
1 lock held by syz-executor.3/16787:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
2 locks held by syz-executor.3/16844:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
2 locks held by syz-executor.5/16985:
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] file_start_write include/linux/fs.h:2707 [inline]
 #0:  (sb_writers#4){.+.+}, at: [<ffffffff818f7442>] do_sendfile+0x912/0xbd0 fs/read_write.c:1440
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] inode_trylock include/linux/fs.h:738 [inline]
 #1:  (&sb->s_type->i_mutex_key#9){++++}, at: [<ffffffff81c19584>] ext4_file_write_iter+0x1f4/0xe90 fs/ext4/file.c:234
4 locks held by kworker/u4:0/11795:
 #0:  ("writeback"){+.+.}, at: [<ffffffff813d223e>] work_static include/linux/workqueue.h:199 [inline]
 #0:  ("writeback"){+.+.}, at: [<ffffffff813d223e>] set_work_data kernel/workqueue.c:619 [inline]
 #0:  ("writeback"){+.+.}, at: [<ffffffff813d223e>] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
 #0:  ("writeback"){+.+.}, at: [<ffffffff813d223e>] process_one_work+0x76e/0x1600 kernel/workqueue.c:2085
 #1:  ((&(&wb->dwork)->work)){+.+.}, at: [<ffffffff813d227b>] process_one_work+0x7ab/0x1600 kernel/workqueue.c:2089
 #2:  (&type->s_umount_key#45){++++}, at: [<ffffffff81900cf0>] trylock_super+0x20/0xf0 fs/super.c:402
 #3:  (&sbi->s_journal_flag_rwsem){.+.+}, at: [<ffffffff817432c0>] do_writepages+0xd0/0x250 mm/page-writeback.c:2361
2 locks held by syz-executor.1/29500:
 #0:  (&type->s_umount_key#45){++++}, at: [<ffffffff81901301>] iterate_supers+0xe1/0x250 fs/super.c:611
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff819978b0>] bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:336 [inline]
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff819978b0>] 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: [<ffffffff81901301>] iterate_supers+0xe1/0x250 fs/super.c:611
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff819978b0>] bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:336 [inline]
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff819978b0>] 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 

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2020/02/03 17:26 linux-4.14.y 9fa690a2a016 93e5e335 .config log report