IPv6: ADDRCONF(NETDEV_UP): hsr0: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready BFS-fs: bfs_fill_super(): No BFS filesystem on loop4 (magic=00000000) INFO: task syz-executor.2:15573 blocked for more than 140 seconds. Not tainted 4.14.258-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D30296 15573 8027 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x1e6/0x350 kernel/locking/rwsem-xadd.c:309 call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:66 [inline] down_read+0x44/0x80 kernel/locking/rwsem.c:26 __get_super.part.0+0x271/0x390 fs/super.c:678 __get_super include/linux/spinlock.h:317 [inline] get_super+0x2b/0x50 fs/super.c:707 fsync_bdev+0x14/0xc0 fs/block_dev.c:495 blkdev_flushbuf block/ioctl.c:430 [inline] blkdev_ioctl+0x883/0x1830 block/ioctl.c:514 block_ioctl+0xd9/0x120 fs/block_dev.c:1893 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fcd69af0e99 RSP: 002b:00007fcd68445168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fcd69c04030 RCX: 00007fcd69af0e99 RDX: 0000000000000000 RSI: 0000000000001261 RDI: 0000000000000003 RBP: 00007fcd69b4aff1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff64d71f0f R14: 00007fcd68445300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1533: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 2 locks held by agetty/7943: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.2/15573: #0: (&type->s_umount_key#74){.+.+}, at: [] __get_super.part.0+0x271/0x390 fs/super.c:678 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1533 Comm: khungtaskd Not tainted 4.14.258-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+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 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: 15565 Comm: syz-executor.2 Not tainted 4.14.258-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880925f4100 task.stack: ffff8880597b8000 RIP: 0010:lookup_bh_lru fs/buffer.c:1324 [inline] RIP: 0010:__find_get_block+0xe1/0xc40 fs/buffer.c:1353 RSP: 0018:ffff8880597bf740 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 000000000000000c RCX: ffffc90005fe0000 RDX: 0000000000040000 RSI: ffffffff8319d715 RDI: ffffffff87ccf280 RBP: 000000000000000c R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: ffff8880925f4100 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000138 R15: 0000000000000000 FS: 00007fcd68466700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0914d78000 CR3: 00000000af859000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __getblk_slow+0x127/0x7a0 fs/buffer.c:1100 __getblk_gfp fs/buffer.c:1383 [inline] __bread_gfp+0x206/0x2e0 fs/buffer.c:1428 sb_bread include/linux/buffer_head.h:309 [inline] udf_tread+0xe1/0x130 fs/udf/misc.c:44 udf_read_tagged+0x40/0x4c0 fs/udf/misc.c:219 udf_check_anchor_block+0x18a/0x590 fs/udf/super.c:1823 udf_scan_anchors+0x16d/0x530 fs/udf/super.c:1863 udf_find_anchor fs/udf/super.c:1928 [inline] udf_load_vrs+0x775/0xa90 fs/udf/super.c:1985 udf_fill_super+0x715/0x1660 fs/udf/super.c:2177 mount_bdev+0x2b3/0x360 fs/super.c:1134 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2572 [inline] do_mount+0xe65/0x2a10 fs/namespace.c:2902 SYSC_mount fs/namespace.c:3118 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3095 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fcd69af0e99 RSP: 002b:00007fcd68466168 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fcd69c03f60 RCX: 00007fcd69af0e99 RDX: 0000000020000040 RSI: 0000000020000280 RDI: 00000000200004c0 RBP: 00007fcd69b4aff1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff64d71f0f R14: 00007fcd68466300 R15: 0000000000022000 Code: 83 c3 01 83 fb 10 0f 84 02 01 00 00 e8 99 55 c2 ff 48 c7 c7 c0 83 93 87 89 dd e8 7b f3 86 01 65 4c 8b 3c ed a0 1c 03 00 4d 85 ff <4d> 89 fc 74 cb e8 75 55 c2 ff 49 8d 7f 18 48 89 fa 48 c1 ea 03 ---------------- Code disassembly (best guess): 0: 83 c3 01 add $0x1,%ebx 3: 83 fb 10 cmp $0x10,%ebx 6: 0f 84 02 01 00 00 je 0x10e c: e8 99 55 c2 ff callq 0xffc255aa 11: 48 c7 c7 c0 83 93 87 mov $0xffffffff879383c0,%rdi 18: 89 dd mov %ebx,%ebp 1a: e8 7b f3 86 01 callq 0x186f39a 1f: 65 4c 8b 3c ed a0 1c mov %gs:0x31ca0(,%rbp,8),%r15 26: 03 00 28: 4d 85 ff test %r15,%r15 * 2b: 4d 89 fc mov %r15,%r12 <-- trapping instruction 2e: 74 cb je 0xfffffffb 30: e8 75 55 c2 ff callq 0xffc255aa 35: 49 8d 7f 18 lea 0x18(%r15),%rdi 39: 48 89 fa mov %rdi,%rdx 3c: 48 c1 ea 03 shr $0x3,%rdx