print_req_error: I/O error, dev nbd4, sector 0 ldm_validate_partition_table(): Disk read failed. Dev nbd4: unable to read RDB block 0 nbd4: unable to read partition table nbd4: partition table beyond EOD, truncated INFO: task syz-executor.4:26641 blocked for more than 140 seconds. Not tainted 4.19.81 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D26544 26641 27708 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 schedule_timeout+0x8c8/0xfc0 kernel/time/timer.c:1782 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 flush_workqueue+0x40f/0x14b0 kernel/workqueue.c:2707 nbd_start_device_ioctl drivers/block/nbd.c:1223 [inline] __nbd_ioctl drivers/block/nbd.c:1294 [inline] nbd_ioctl+0xb52/0xcb0 drivers/block/nbd.c:1334 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0xc38/0x1ab6 block/ioctl.c:601 block_ioctl+0xee/0x130 fs/block_dev.c:1891 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459f49 Code: Bad RIP value. RSP: 002b:00007f4d16283c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459f49 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000006 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4d162846d4 R13: 00000000004c3a06 R14: 00000000004d7a98 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1038: #0: 000000006b06cfa0 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438 3 locks held by rs:main Q:Reg/7355: #0: 000000008596f024 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 #1: 000000007d8760d0 (sb_writers#4){.+.+}, at: file_start_write include/linux/fs.h:2775 [inline] #1: 000000007d8760d0 (sb_writers#4){.+.+}, at: vfs_write+0x429/0x560 fs/read_write.c:548 #2: 000000009d50becc (&sb->s_type->i_mutex_key#9){++++}, at: inode_lock include/linux/fs.h:747 [inline] #2: 000000009d50becc (&sb->s_type->i_mutex_key#9){++++}, at: __generic_file_fsync+0xb5/0x200 fs/libfs.c:985 1 lock held by rsyslogd/7357: #0: 00000000689d92b7 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 2 locks held by getty/7479: #0: 0000000018a76e5d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000c9090589 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7480: #0: 0000000095b1cb42 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000e145f0d2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7481: #0: 000000007d2fc280 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000668117d6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7482: #0: 00000000b73784df (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000001a06afd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7483: #0: 00000000729ae22f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000047b1e080 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7484: #0: 00000000c725127f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000e24fddcf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7485: #0: 000000000ad08fa3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000adad95ed (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by kworker/u5:2/9487: #0: 00000000424cb892 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000424cb892 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000424cb892 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 00000000424cb892 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 00000000424cb892 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 00000000424cb892 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 00000000424cb892 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124 #1: 00000000934b4c80 ((work_completion)(&args->work)){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128 1 lock held by syz-executor.5/30050: #0: 000000007d8760d0 (sb_writers#4){.+.+}, at: file_start_write include/linux/fs.h:2775 [inline] #0: 000000007d8760d0 (sb_writers#4){.+.+}, at: do_sendfile+0x9b9/0xce0 fs/read_write.c:1446 1 lock held by syz-executor.5/7705: 2 locks held by kworker/u4:2/8368: #0: 00000000f271810e (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1821 [inline] #0: 00000000f271810e (&rq->lock){-.-.}, at: __schedule+0x1f8/0x1dc0 kernel/sched/core.c:3453 #1: 00000000804848c8 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128 2 locks held by syz-executor.3/10922: #0: 000000007d8760d0 (sb_writers#4){.+.+}, at: file_start_write include/linux/fs.h:2775 [inline] #0: 000000007d8760d0 (sb_writers#4){.+.+}, at: do_sendfile+0x9b9/0xce0 fs/read_write.c:1446 #1: 00000000f271810e (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1821 [inline] #1: 00000000f271810e (&rq->lock){-.-.}, at: __schedule+0x1f8/0x1dc0 kernel/sched/core.c:3453 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1038 Comm: khungtaskd Not tainted 4.19.81 #0 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+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 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+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 30050 Comm: syz-executor.5 Not tainted 4.19.81 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:784 [inline] RIP: 0010:check_preemption_disabled+0x93/0x290 lib/smp_processor_id.c:18 Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 3f 01 00 00 48 83 3d 5a 39 4e 05 00 0f 84 2a 01 00 00 e8 4f ba 46 fe 9c 58 <0f> 1f 44 00 00 25 00 02 00 00 31 ff 48 89 c3 48 89 c6 e8 d6 bb 46 RSP: 0018:ffff888038a5f110 EFLAGS: 00000093 RAX: 0000000000000093 RBX: 0000000000000000 RCX: ffffffff83240c9a RDX: 0000000000000000 RSI: ffffffff83240cf1 RDI: 0000000000000005 RBP: ffff888038a5f140 R08: ffff88808abcc180 R09: ffff88809a430500 R10: ffffed1015d04732 R11: ffff8880ae823993 R12: ffffffff87823d40 R13: 0000000000000000 R14: ffffffff87560d60 R15: 0000000000000001 FS: 00007f82f5ada700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 0000000047c0a000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __this_cpu_preempt_check+0x1d/0x30 lib/smp_processor_id.c:62 lookup_bh_lru fs/buffer.c:1262 [inline] __find_get_block+0xfa/0xcf0 fs/buffer.c:1291 __getblk_gfp+0x38/0x970 fs/buffer.c:1317 sb_getblk include/linux/buffer_head.h:325 [inline] __ext4_get_inode_loc+0x362/0x10d0 fs/ext4/inode.c:4587 ext4_write_inode+0x313/0x510 fs/ext4/inode.c:5419 write_inode fs/fs-writeback.c:1227 [inline] __writeback_single_inode+0xc74/0x12c0 fs/fs-writeback.c:1426 writeback_single_inode+0x2c1/0x420 fs/fs-writeback.c:1480 sync_inode fs/fs-writeback.c:2517 [inline] sync_inode_metadata+0xa8/0xe0 fs/fs-writeback.c:2537 __generic_file_fsync+0x169/0x200 fs/libfs.c:992 ext4_sync_file+0x826/0x1450 fs/ext4/fsync.c:120 vfs_fsync_range+0x141/0x230 fs/sync.c:197 generic_write_sync include/linux/fs.h:2746 [inline] ext4_file_write_iter+0x7a0/0x1060 fs/ext4/file.c:281 call_write_iter include/linux/fs.h:1820 [inline] do_iter_readv_writev+0x558/0x830 fs/read_write.c:681 do_iter_write fs/read_write.c:960 [inline] do_iter_write+0x184/0x5f0 fs/read_write.c:941 vfs_iter_write+0x77/0xb0 fs/read_write.c:973 iter_file_splice_write+0x661/0xbd0 fs/splice.c:750 do_splice_from fs/splice.c:852 [inline] direct_splice_actor+0x123/0x190 fs/splice.c:1019 splice_direct_to_actor+0x2e7/0x890 fs/splice.c:974 do_splice_direct+0x1da/0x2a0 fs/splice.c:1062 do_sendfile+0x597/0xce0 fs/read_write.c:1447 __do_sys_sendfile64 fs/read_write.c:1502 [inline] __se_sys_sendfile64 fs/read_write.c:1494 [inline] __x64_sys_sendfile64+0x15a/0x220 fs/read_write.c:1494 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459f49 Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f82f5ad9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459f49 RDX: 00000000200001c0 RSI: 0000000000000003 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 00008080fffffffe R11: 0000000000000246 R12: 00007f82f5ada6d4 R13: 00000000004c7b7f R14: 00000000004ddc78 R15: 00000000ffffffff