kernel msg: ebtables bug: please report to author: counter_offset != totalcnt INFO: task syz-executor6:25693 blocked for more than 140 seconds. Not tainted 4.18.0+ #189 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor6 D24040 25693 24338 0x00000004 Call Trace: context_switch kernel/sched/core.c:2823 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3471 schedule+0xfb/0x450 kernel/sched/core.c:3515 wb_wait_for_completion+0x201/0x2e0 fs/fs-writeback.c:221 sync_inodes_sb+0x33e/0x480 fs/fs-writeback.c:2424 sync_inodes_one_sb+0x59/0x70 fs/sync.c:74 iterate_supers+0x149/0x290 fs/super.c:630 ksys_sync+0xec/0x1e0 fs/sync.c:113 __ia32_sys_sync+0xe/0x20 fs/sync.c:124 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457089 Code: 08 e8 3b a9 fb ff 48 8b 44 24 20 48 8b 4c 24 18 48 8b 54 24 38 48 8b 7c 24 48 eb 8d 48 8b 6c 24 50 48 83 c4 58 c3 48 89 04 24 <48> 89 5c 24 08 e8 0d a9 fb ff 48 8b 44 24 40 48 8b 4c 24 48 48 8b RSP: 002b:00007fc598ad8c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007fc598ad96d4 RCX: 0000000000457089 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d5f78 R14: 00000000004c7f98 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/775: #0: 0000000063686300 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 2 locks held by rs:main Q:Reg/4251: #0: 000000007bee0d64 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 #1: 00000000010a6894 (sb_writers#6){.+.+}, at: file_start_write include/linux/fs.h:2752 [inline] #1: 00000000010a6894 (sb_writers#6){.+.+}, at: vfs_write+0x452/0x560 fs/read_write.c:548 1 lock held by rsyslogd/4253: #0: 0000000074625cf6 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/4343: #0: 00000000b97e6a6c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000050baf128 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4344: #0: 0000000083eb1c63 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000c64405a8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4345: #0: 000000004572728b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000fa5086f1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4346: #0: 00000000aef6fba9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000d5946448 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4347: #0: 00000000e38979ba (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000096da4303 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4348: #0: 00000000f1307625 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000008b262891 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4349: #0: 00000000f1d0b29f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000002b0ce1dc (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 3 locks held by kworker/u4:4/6890: 1 lock held by syz-executor6/25693: #0: 00000000f19c2dcd (&type->s_umount_key#44){++++}, at: iterate_supers+0xe2/0x290 fs/super.c:628 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 775 Comm: khungtaskd Not tainted 4.18.0+ #189 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+0x1c9/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 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:196 [inline] watchdog+0x9c4/0xf80 kernel/hung_task.c:252 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6890 Comm: kworker/u4:4 Not tainted 4.18.0+ #189 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:find_get_entry+0x0/0xc90 include/linux/compiler.h:188 Code: b3 20 00 e9 f6 f1 ff ff 48 89 df e8 7a b3 20 00 e9 00 f6 ff ff 4c 89 ef e8 cd b2 20 00 e9 d0 f5 ff ff 0f 1f 84 00 00 00 00 00 <55> 48 89 e5 41 57 41 56 48 8d 85 38 fd ff ff 41 55 48 c1 e8 03 4c RSP: 0018:ffff8801b89e60f0 EFLAGS: 00000293 RAX: ffff8801d929e5c0 RBX: 0000000000000003 RCX: 0000000000620848 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8801da8063d8 RBP: ffff8801b89e63b8 R08: ffff8801d929e5c0 R09: ffffed003b6246d6 R10: 0000000000000003 R11: 0000000000000003 R12: dffffc0000000000 R13: 0000000000000007 R14: 0000000000620848 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001b9dc5000 CR4: 00000000001406e0 DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: find_or_create_page include/linux/pagemap.h:322 [inline] grow_dev_page fs/buffer.c:940 [inline] grow_buffers fs/buffer.c:1009 [inline] __getblk_slow fs/buffer.c:1036 [inline] __getblk_gfp+0x3bb/0xb10 fs/buffer.c:1313 __bread_gfp+0x2d/0x310 fs/buffer.c:1347 sb_bread include/linux/buffer_head.h:307 [inline] __fat_write_inode+0x324/0xcc0 fs/fat/inode.c:864 fat_write_inode+0x97/0x180 fs/fat/inode.c:916 write_inode fs/fs-writeback.c:1183 [inline] __writeback_single_inode+0xf33/0x15e0 fs/fs-writeback.c:1382 writeback_sb_inodes+0x71f/0x11d0 fs/fs-writeback.c:1587 __writeback_inodes_wb+0x1b8/0x340 fs/fs-writeback.c:1656 wb_writeback+0x9f1/0xf80 fs/fs-writeback.c:1765 wb_check_old_data_flush fs/fs-writeback.c:1867 [inline] wb_do_writeback fs/fs-writeback.c:1920 [inline] wb_workfn+0xfb7/0x1760 fs/fs-writeback.c:1949 process_one_work+0xc73/0x1ba0 kernel/workqueue.c:2153 worker_thread+0x189/0x13c0 kernel/workqueue.c:2296 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413