INFO: task syz.2.1816:10877 blocked for more than 430 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1816 state:D stack:0 pid:10877 tgid:10877 ppid:10483 task_flags:0x400040 flags:0x00000005 Call trace: [<81b5c47c>] (__schedule) from [<81b5d914>] (__schedule_loop kernel/sched/core.c:7311 [inline]) [<81b5c47c>] (__schedule) from [<81b5d914>] (schedule+0x2c/0xec kernel/sched/core.c:7326) r10:838e8980 r9:847f1880 r8:85983500 r7:859d9c28 r6:e023dea0 r5:e023de30 r4:847f1880 [<81b5d8e8>] (schedule) from [<8079fbe0>] (request_wait_answer fs/fuse/dev.c:743 [inline]) [<81b5d8e8>] (schedule) from [<8079fbe0>] (__fuse_request_send fs/fuse/dev.c:757 [inline]) [<81b5d8e8>] (schedule) from [<8079fbe0>] (fuse_chan_send+0x390/0x47c fs/fuse/dev.c:833) r5:e023de30 r4:859d9bd0 [<8079f850>] (fuse_chan_send) from [<807b2138>] (__fuse_simple_request+0x5c/0x68 fs/fuse/req.c:69) r8:864e6300 r7:84fc9fc0 r6:86253200 r5:868916c0 r4:e023dea0 [<807b20dc>] (__fuse_simple_request) from [<807a78d4>] (fuse_simple_request fs/fuse/fuse_i.h:1012 [inline]) [<807b20dc>] (__fuse_simple_request) from [<807a78d4>] (fuse_flush+0x178/0x1b4 fs/fuse/file.c:504) r5:850478c0 r4:838e8980 [<807a775c>] (fuse_flush) from [<805997b0>] (filp_flush+0x38/0x88 fs/open.c:1471) r8:86253240 r7:845be380 r6:0000001e r5:86253200 r4:838e8980 [<80599778>] (filp_flush) from [<80599814>] (filp_close+0x14/0x28 fs/open.c:1484) r7:845be380 r6:0000001e r5:838e8980 r4:86253200 [<80599800>] (filp_close) from [<805cbdbc>] (__range_close fs/file.c:793 [inline]) [<80599800>] (filp_close) from [<805cbdbc>] (__do_sys_close_range fs/file.c:854 [inline]) [<80599800>] (filp_close) from [<805cbdbc>] (sys_close_range+0x18c/0x224 fs/file.c:818) r5:00000005 r4:86253200 [<805cbc30>] (sys_close_range) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe023dfa8 to 0xe023dff0) dfa0: 00000000 00000000 00000003 0000001e 00000000 7ec7e918 dfc0: 00000000 00000000 00000000 000001b4 7ec7e918 00000000 00000000 00356384 dfe0: 7ec7e840 7ec7e830 0002853c 001308d0 r10:000001b4 r9:847f1880 r8:8020029c r7:000001b4 r6:00000000 r5:00000000 r4:00000000 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 29 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: ARM-Versatile Express Call trace: [<80201998>] (dump_backtrace) from [<80201a8c>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257) r7:60000093 r6:60000093 r5:82332b74 r4:00000000 [<80201a74>] (show_stack) from [<8021e580>] (__dump_stack lib/dump_stack.c:94 [inline]) [<80201a74>] (show_stack) from [<8021e580>] (dump_stack_lvl+0x5c/0x70 lib/dump_stack.c:120) [<8021e524>] (dump_stack_lvl) from [<8021e5ac>] (dump_stack+0x18/0x1c lib/dump_stack.c:129) r7:00000000 r6:00000013 r5:00000001 r4:00000001 [<8021e594>] (dump_stack) from [<81b45b1c>] (nmi_cpu_backtrace+0x150/0x170 lib/nmi_backtrace.c:122) [<81b459cc>] (nmi_cpu_backtrace) from [<81b45c70>] (nmi_trigger_cpumask_backtrace+0x134/0x208 lib/nmi_backtrace.c:65) r7:82a0b150 r6:83178000 r5:82a1c7b8 r4:ffffffff [<81b45b3c>] (nmi_trigger_cpumask_backtrace) from [<8022f0f4>] (arch_trigger_cpumask_backtrace+0x18/0x1c arch/arm/kernel/smp.c:851) r9:82a0b2f0 r8:00000001 r7:82a1ce80 r6:82ccae2c r5:00007f2b r4:00000048 [<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b4d7ac>] (trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]) [<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b4d7ac>] (__sys_info lib/sys_info.c:157 [inline]) [<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b4d7ac>] (sys_info+0x68/0xa8 lib/sys_info.c:165) [<81b4d744>] (sys_info) from [<8038f838>] (check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]) [<81b4d744>] (sys_info) from [<8038f838>] (watchdog+0x3a0/0x848 kernel/hung_task.c:561) r5:00007f2b r4:0000000a [<8038f498>] (watchdog) from [<80281710>] (kthread+0x11c/0x154 kernel/kthread.c:436) r10:00000000 r9:df819e60 r8:83110980 r7:00000000 r6:8038f498 r5:83178000 r4:8387c600 [<802815f4>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137) Exception stack(0xdf8d5fb0 to 0xdf8d5ff8) 5fa0: 00000000 00000000 00000000 00000000 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:802815f4 r4:8387c600 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 3099 Comm: sshd-session Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: ARM-Versatile Express PC is at __sys_shutdown+0x14/0xa8 net/socket.c:2535 LR is at class_fd_constructor include/linux/file.h:83 [inline] LR is at __sys_shutdown+0x14/0xa8 net/socket.c:2533 pc : [<81626094>] lr : [<81626094>] psr: 40030013 sp : df96df70 ip : df96df70 fp : df96df94 r10: 00000125 r9 : 8432ee40 r8 : 8020029c r7 : 00000001 r6 : 008b11d8 r5 : 0054613c r4 : 008bc578 r3 : 0c2e0003 r2 : 841fd554 r1 : 00000001 r0 : 8385a900 Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85ca6180 DAC: fffffffd Call trace: [<81626080>] (__sys_shutdown) from [<81626138>] (__do_sys_shutdown net/socket.c:2546 [inline]) [<81626080>] (__sys_shutdown) from [<81626138>] (sys_shutdown+0x10/0x14 net/socket.c:2544) r9:8432ee40 r8:8020029c r7:00000125 r6:008b11d8 r5:0054613c r4:008bc578 [<81626128>] (sys_shutdown) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf96dfa8 to 0xdf96dff0) dfa0: 008bc578 0054613c 00000009 00000001 00000000 00000000 dfc0: 008bc578 0054613c 008b11d8 00000125 00000006 0053e0a8 00000000 00000003 dfe0: 00564ccc 7eeaa0dc 004e3820 769d612c