INFO: task syz-executor313:8110 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-executor313 D27504 8110 8108 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: 0033:0x7fbf4ad3b4c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fbf4acec2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007fbf4adcc4c0 RCX: 00007fbf4ad3b4c9 RDX: 00007fbf4ad3b4c9 RSI: 0000000000000000 RDI: 00000000200001c0 RBP: 00007fbf4ad99164 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007fbf4ad95158 R14: 00007fbf4ad97160 R15: 00007fbf4adcc4c8 Showing all locks held in the system: 1 lock held by khungtaskd/1570: #0: 000000003edd9b83 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7805: #0: 000000008d495c16 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by syz-executor313/8110: #0: 00000000a419ffe6 (sb_writers#11){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline] #0: 00000000a419ffe6 (sb_writers#11){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360 #1: 00000000365c8ea8 (&sb->s_type->i_mutex_key#17){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #1: 00000000365c8ea8 (&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 01/01/2011 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 01/01/2011 RIP: 0010:_raw_spin_lock+0x1/0x40 kernel/locking/spinlock.c:143 Code: 82 f1 89 e8 71 16 7f f9 e9 2d fe ff ff 48 89 df e8 64 16 7f f9 e9 63 fe ff ff 4c 89 ef e8 77 17 7f f9 e9 2e ff ff ff 90 90 55 <48> 89 fd bf 01 00 00 00 e8 02 22 28 f9 45 31 c9 41 b8 01 00 00 00 RSP: 0018:ffff8880b5a67d78 EFLAGS: 00000282 RAX: fffffbfff148be2c RBX: ffffffff89f88322 RCX: ffffffff89f88330 RDX: 0000000000000004 RSI: 0000000000000001 RDI: ffffffff89f889c0 RBP: ffffffff89f88280 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000000 R12: 000000010000cb2c R13: ffffffff89f88330 R14: dffffc0000000000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd1589f3000 CR3: 00000000a1017000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: spin_lock include/linux/spinlock.h:329 [inline] rcu_gp_init kernel/rcu/tree.c:1939 [inline] rcu_gp_kthread+0x505/0x21c0 kernel/rcu/tree.c:2178 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: f1 icebp 1: 89 e8 mov %ebp,%eax 3: 71 16 jno 0x1b 5: 7f f9 jg 0x0 7: e9 2d fe ff ff jmpq 0xfffffe39 c: 48 89 df mov %rbx,%rdi f: e8 64 16 7f f9 callq 0xf97f1678 14: e9 63 fe ff ff jmpq 0xfffffe7c 19: 4c 89 ef mov %r13,%rdi 1c: e8 77 17 7f f9 callq 0xf97f1798 21: e9 2e ff ff ff jmpq 0xffffff54 26: 90 nop 27: 90 nop 28: 55 push %rbp * 29: 48 89 fd mov %rdi,%rbp <-- trapping instruction 2c: bf 01 00 00 00 mov $0x1,%edi 31: e8 02 22 28 f9 callq 0xf9282238 36: 45 31 c9 xor %r9d,%r9d 39: 41 b8 01 00 00 00 mov $0x1,%r8d