INFO: task syz-executor320:7990 blocked for more than 140 seconds. Not tainted 4.14.291-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor320 D28560 7990 7988 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 fuse_wait_on_page_writeback fs/fuse/file.c:385 [inline] fuse_wait_on_page_writeback.isra.0+0xdc/0x120 fs/fuse/file.c:381 fuse_launder_page fs/fuse/file.c:2042 [inline] fuse_launder_page+0xa2/0xd0 fs/fuse/file.c:2035 do_launder_page mm/truncate.c:609 [inline] invalidate_inode_pages2_range+0x547/0xc00 mm/truncate.c:685 fuse_finish_open+0x262/0x500 fs/fuse/file.c:181 fuse_open_common+0x234/0x290 fs/fuse/file.c:224 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3571 do_filp_open+0x179/0x3c0 fs/namei.c:3605 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f3d272564c9 RSP: 002b:00007f3d272072f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f3d272e74c0 RCX: 00007f3d272564c9 RDX: 0000000000000000 RSI: 0000000000000600 RDI: 0000000020000100 RBP: 00007f3d272b4164 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007f3d272b0158 R14: 00007f3d272b2160 R15: 00007f3d272e74c8 Showing all locks held in the system: 1 lock held by khungtaskd/1532: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 1 lock held by in:imklog/7667: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0x1fb/0x2b0 fs/file.c:819 2 locks held by syz-executor320/7990: #0: (sb_writers#10){.+.+}, at: [] sb_start_write include/linux/fs.h:1551 [inline] #0: (sb_writers#10){.+.+}, at: [] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 #1: (&sb->s_type->i_mutex_key#17){+.+.}, at: [] inode_lock include/linux/fs.h:719 [inline] #1: (&sb->s_type->i_mutex_key#17){+.+.}, at: [] fuse_open_common+0x1a4/0x290 fs/fuse/file.c:217 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1532 Comm: khungtaskd Not tainted 4.14.291-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 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: 4608 Comm: systemd-journal Not tainted 4.14.291-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 task: ffff8880a22c4440 task.stack: ffff8880a22c8000 RIP: 0010:__lock_acquire+0x452/0x3f20 kernel/locking/lockdep.c:3446 RSP: 0018:ffff8880a22cf8f0 EFLAGS: 00000097 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000007 RSI: 1ffff1101445899d RDI: ffff8880a22c4cb4 RBP: 0000000000000002 R08: 0000000000000001 R09: 0000000000000001 R10: ffff8880a22c4cf0 R11: ffff8880a22c4440 R12: ffff8880a22c4d08 R13: 00000000000000bb R14: 00000000000000bb R15: ffffffff8becddc0 FS: 00007f48b21d08c0(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f48af5a3000 CR3: 00000000a231a000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 seqcount_lockdep_reader_access include/linux/seqlock.h:81 [inline] read_seqcount_begin include/linux/seqlock.h:164 [inline] set_root+0x125/0x550 fs/namei.c:835 path_init+0xee3/0x1a20 fs/namei.c:2220 path_parentat+0x22/0x120 fs/namei.c:2394 filename_parentat+0x176/0x520 fs/namei.c:2420 filename_create+0x8a/0x3f0 fs/namei.c:3659 user_path_create fs/namei.c:3734 [inline] SYSC_mkdirat fs/namei.c:3866 [inline] SyS_mkdirat+0x95/0x270 fs/namei.c:3858 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f48b148b687 RSP: 002b:00007fffddf31418 EFLAGS: 00000293 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007fffddf34480 RCX: 00007f48b148b687 RDX: 0000000000000000 RSI: 00000000000001ed RDI: 00005606d2fec8a0 RBP: 00007fffddf31450 R08: 00005606d21673e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 00005606d2fec8a0 R15: 00007fffddf31a90 Code: 48 ba 00 00 00 00 00 fc ff df 0f b6 0c 11 48 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 dd 25 00 00 41 83 bb 74 08 00 00 01 <49> 8d 7a 24 48 89 fa 83 d8 ff c1 e3 0f c1 e0 0d c1 e5 10 0f b7