INFO: task syz-executor994:8099 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-executor994 D28248 8099 8094 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 fuse_wait_on_page_writeback fs/fuse/file.c:383 [inline] fuse_wait_on_page_writeback.isra.0+0x11b/0x170 fs/fuse/file.c:379 fuse_launder_page fs/fuse/file.c:2033 [inline] fuse_launder_page+0xb6/0xe0 fs/fuse/file.c:2026 do_launder_page mm/truncate.c:655 [inline] invalidate_inode_pages2_range+0x795/0x1110 mm/truncate.c:725 fuse_finish_open+0x2e2/0x590 fs/fuse/file.c:182 fuse_open_common+0x254/0x2c0 fs/fuse/file.c:222 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f29dd6434c9 Code: Bad RIP value. RSP: 002b:00007f29dd5d32f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007f29dd6d44d0 RCX: 00007f29dd6434c9 RDX: 00007f29dd6434c9 RSI: 0000000000000000 RDI: 00000000200001c0 RBP: 00007f29dd6a1164 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007f29dd69d158 R14: 00007f29dd69f160 R15: 00007f29dd6d44d8 Showing all locks held in the system: 1 lock held by khungtaskd/1570: #0: 000000007e56b580 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7798: #0: 000000009af91d1e (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by syz-executor994/8099: #0: 00000000289a851f (sb_writers#11){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline] #0: 00000000289a851f (sb_writers#11){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360 #1: 0000000050b7a538 (&sb->s_type->i_mutex_key#17){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #1: 0000000050b7a538 (&sb->s_type->i_mutex_key#17){+.+.}, at: fuse_open_common+0x1bc/0x2c0 fs/fuse/file.c:215 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 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: 10 Comm: rcu_preempt Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:2318 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:2337 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:2391 [inline] RIP: 0010:__lock_acquire+0xbed/0x3ff0 kernel/locking/lockdep.c:3416 Code: db 74 55 48 83 eb 08 74 4f 48 bd 00 00 00 00 00 fc ff df eb 06 48 83 eb 08 74 3d 48 8d 7b 18 48 89 f8 48 c1 e8 03 80 3c 28 00 <0f> 85 8c 1e 00 00 4c 3b 63 18 0f 84 f1 fc ff ff 48 8d 7b 08 48 89 RSP: 0018:ffff8880b5a67980 EFLAGS: 00000046 RAX: 1ffffffff18e4be3 RBX: ffffffff8c725f00 RCX: 0000000000000ff8 RDX: 1ffffffff19a3ea0 RSI: 000000008dae0b10 RDI: ffffffff8c725f18 RBP: dffffc0000000000 R08: ffffffff8cd1f500 R09: 0000000000000000 R10: ffff8880b5a4eb08 R11: 0000000000000000 R12: a8b925c7f0ce6f64 R13: ffff8880b5a4e280 R14: ffff8880b5a4eb20 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa874eb4018 CR3: 00000000a106f000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:152 __free_object+0x17/0x1e0 lib/debugobjects.c:251 free_object lib/debugobjects.c:272 [inline] debug_object_free lib/debugobjects.c:652 [inline] debug_object_free+0x1cc/0x380 lib/debugobjects.c:624 destroy_timer_on_stack kernel/time/timer.c:753 [inline] schedule_timeout+0x4e6/0xfe0 kernel/time/timer.c:1822 rcu_gp_kthread+0xdad/0x21c0 kernel/rcu/tree.c:2202 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415