INFO: task syz-executor379:8111 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-executor379 D27512 8111 8109 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: 0033:0x7f66e38174c9 Code: Bad RIP value. RSP: 002b:00007f66e37c82f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007f66e38a84c0 RCX: 00007f66e38174c9 RDX: 00007f66e38174c9 RSI: 0000000000000000 RDI: 00000000200001c0 RBP: 00007f66e3875164 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007f66e3871158 R14: 00007f66e3873160 R15: 00007f66e38a84c8 Showing all locks held in the system: 1 lock held by khungtaskd/1570: #0: 00000000e7d4009a (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7767: #0: 00000000ecc62b4a (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by syz-executor379/8111: #0: 00000000731f07c0 (sb_writers#11){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline] #0: 00000000731f07c0 (sb_writers#11){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360 #1: 000000008f063a06 (&sb->s_type->i_mutex_key#17){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #1: 000000008f063a06 (&sb->s_type->i_mutex_key#17){+.+.}, at: fuse_open_common+0x1bc/0x2c0 fs/fuse/file.c:215 ============================================= NMI backtrace for cpu 0 CPU: 0 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 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60