INFO: task syz-executor.1:18601 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D29592 18601 23735 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x20a/0x390 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:83 [inline] down_read+0x44/0x80 kernel/locking/rwsem.c:26 __get_super.part.0+0x209/0x2e0 fs/super.c:698 __get_super include/linux/spinlock.h:329 [inline] get_super+0x2b/0x50 fs/super.c:727 fsync_bdev+0x14/0xc0 fs/block_dev.c:483 blkdev_flushbuf block/ioctl.c:436 [inline] blkdev_ioctl+0x912/0x1a80 block/ioctl.c:521 block_ioctl+0xe9/0x130 fs/block_dev.c:1906 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7feca9a33409 Code: Bad RIP value. RSP: 002b:00007feca83a8168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007feca9b45f80 RCX: 00007feca9a33409 RDX: 0000000000000000 RSI: 0000000000001261 RDI: 0000000000000003 RBP: 00007feca9a8e367 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc49995f1f R14: 00007feca83a8300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1571: #0: 00000000aa096fea (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7821: #0: 0000000005d7a2ef (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 3 locks held by kworker/u4:8/9642: 1 lock held by syz-executor.0/14077: 1 lock held by syz-executor.5/14485: 1 lock held by syz-executor.3/14489: 1 lock held by syz-executor.2/15136: 1 lock held by syz-executor.4/16199: 1 lock held by syz-executor.1/23649: 1 lock held by syz-executor.1/18601: #0: 000000008951d5c4 (&type->s_umount_key#75){++++}, at: __get_super.part.0+0x209/0x2e0 fs/super.c:698 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1571 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 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: 9642 Comm: kworker/u4:8 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Workqueue: bat_events batadv_nc_worker RIP: 0010:do_raw_spin_lock+0x141/0x220 kernel/locking/spinlock_debug.c:115 Code: 89 ea 89 5d 08 48 c1 ea 03 65 4c 8b 24 25 c0 df 01 00 80 3c 02 00 0f 85 ab 00 00 00 4c 89 65 10 48 83 c4 08 5b 5d 41 5c 41 5d 48 c7 c6 40 76 6a 88 48 89 ef e8 0f fd ff ff e9 68 ff ff ff 48 RSP: 0018:ffff888051c2fc38 EFLAGS: 00000286 RAX: dffffc0000000000 RBX: ffff88805bf31250 RCX: ffffffff814bdebb RDX: 1ffff1100b7e624c RSI: 0000000000000004 RDI: ffff88805bf31250 RBP: ffff8880b3201770 R08: 0000000000000001 R09: ffffed100b7e624a R10: ffff88805bf31253 R11: 0000000000000000 R12: dffffc0000000000 R13: ffffffff87d8d930 R14: 0000000000000016 R15: ffff8880b4aa16c0 FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555557445848 CR3: 000000004aee0000 CR4: 00000000003406f0 DR0: 00000000ffff070c DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: spin_lock_bh include/linux/spinlock.h:334 [inline] batadv_nc_purge_paths+0xdc/0x310 net/batman-adv/network-coding.c:453 batadv_nc_worker+0x731/0xd50 net/batman-adv/network-coding.c:733 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415