INFO: task syz-executor.1:6297 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 D30000 6297 8158 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: 0033:0x7f3b50cb70c9 Code: Bad RIP value. RSP: 002b:00007f3b4f208168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f3b50dd7050 RCX: 00007f3b50cb70c9 RDX: 0000000000000000 RSI: 0000000000001261 RDI: 0000000000000003 RBP: 00007f3b50d12ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd8130896f R14: 00007f3b4f208300 R15: 0000000000022000 Showing all locks held in the system: 2 locks held by kworker/u4:2/27: 1 lock held by khungtaskd/1571: #0: 000000000254dc24 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7798: #0: 0000000023c19ab4 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 1 lock held by syz-executor.1/6292: 1 lock held by syz-executor.1/6297: #0: 000000009fe3e467 (&type->s_umount_key#88){++++}, at: __get_super.part.0+0x209/0x2e0 fs/super.c:698 2 locks held by syz-executor.1/6617: #0: 00000000caafb589 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x90/0x3b0 fs/super.c:1125 #1: 000000009fe3e467 (&type->s_umount_key#88){++++}, at: grab_super+0xa2/0x350 fs/super.c:383 1 lock held by syz-executor.1/6618: #0: 000000009fe3e467 (&type->s_umount_key#88){++++}, at: __get_super.part.0+0x209/0x2e0 fs/super.c:698 1 lock held by syz-executor.0/7914: 2 locks held by syz-executor.1/7913: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1571 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 16457 Comm: syz-fuzzer Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 RIP: 0033:0x4fa084 Code: 0a 00 41 81 e1 ff ff 01 00 4d 89 e2 49 81 e4 ff 7f 00 00 46 8b 6c 88 68 46 89 ac a0 68 00 08 00 4c 8b a0 68 00 0a 00 4d 01 d4 <46> 89 64 88 68 e9 6e ff ff ff 4d 89 ca e9 66 ff ff ff 4c 89 88 70 RSP: 002b:000000c00005d6d0 EFLAGS: 00000202 RAX: 000000c016fb6000 RBX: 000000c00c640000 RCX: 000000000000f148 RDX: 0000000000010000 RSI: 0000000000002b02 RDI: 0000000000004001 RBP: 000000c00005d730 R08: 000000000000f1e2 R09: 0000000000000000 R10: 000000000000f144 R11: 0000000000000000 R12: 0000000000e27145 R13: 0000000000e27144 R14: 000000c0000016c0 R15: 00000000000070e0 FS: 000000c013340c90 GS: 0000000000000000