INFO: task syz.6.8893:30286 blocked for more than 430 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.8893 state:D stack:0 pid:30286 tgid:30286 ppid:25699 task_flags:0x400040 flags:0x00000005 Call trace: [<81b36cd0>] (__schedule) from [<81b38168>] (__schedule_loop kernel/sched/core.c:7307 [inline]) [<81b36cd0>] (__schedule) from [<81b38168>] (schedule+0x2c/0x134 kernel/sched/core.c:7322) r10:8744b380 r9:83184980 r8:89c59a00 r7:84d00a68 r6:e022dea8 r5:e022de50 r4:83184980 [<81b3813c>] (schedule) from [<80794fb0>] (request_wait_answer fs/fuse/dev.c:590 [inline]) [<81b3813c>] (schedule) from [<80794fb0>] (__fuse_request_send fs/fuse/dev.c:604 [inline]) [<81b3813c>] (schedule) from [<80794fb0>] (__fuse_simple_request+0x3b8/0x520 fs/fuse/dev.c:699) r5:e022de50 r4:84d00a10 [<80794bf8>] (__fuse_simple_request) from [<8079e5a4>] (fuse_simple_request fs/fuse/fuse_i.h:1262 [inline]) [<80794bf8>] (__fuse_simple_request) from [<8079e5a4>] (fuse_flush+0x178/0x1b4 fs/fuse/file.c:500) r8:8748ce00 r7:85f99600 r6:85e2ed00 r5:837a0900 r4:8744b380 [<8079e42c>] (fuse_flush) from [<8059133c>] (filp_flush+0x38/0x88 fs/open.c:1498) r8:85e2ed40 r7:860bb3c0 r6:0000001e r5:85e2ed00 r4:8744b380 [<80591304>] (filp_flush) from [<805913a0>] (filp_close+0x14/0x28 fs/open.c:1511) r7:860bb3c0 r6:0000001e r5:8744b380 r4:85e2ed00 [<8059138c>] (filp_close) from [<805c38c0>] (__range_close fs/file.c:793 [inline]) [<8059138c>] (filp_close) from [<805c38c0>] (__do_sys_close_range fs/file.c:854 [inline]) [<8059138c>] (filp_close) from [<805c38c0>] (sys_close_range+0x18c/0x224 fs/file.c:818) r5:00000005 r4:85e2ed00 [<805c3734>] (sys_close_range) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe022dfa8 to 0xe022dff0) dfa0: 00000000 00000000 00000003 0000001e 00000000 7ea6f918 dfc0: 00000000 00000000 00000000 000001b4 0050a08a ffffffff 00000000 003462e4 dfe0: 7ea6f840 7ea6f830 0002853c 00130820 r10:000001b4 r9:83184980 r8:8020029c r7:000001b4 r6:00000000 r5:00000000 r4:00000000 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express Call trace: [<80201998>] (dump_backtrace) from [<80201a8c>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257) r7:60000193 r6:60000193 r5:82328eb0 r4:00000000 [<80201a74>] (show_stack) from [<8021e4ac>] (__dump_stack lib/dump_stack.c:94 [inline]) [<80201a74>] (show_stack) from [<8021e4ac>] (dump_stack_lvl+0x5c/0x70 lib/dump_stack.c:120) [<8021e450>] (dump_stack_lvl) from [<8021e4d8>] (dump_stack+0x18/0x1c lib/dump_stack.c:129) r7:00000000 r6:00000113 r5:00000000 r4:00000001 [<8021e4c0>] (dump_stack) from [<81b20368>] (nmi_cpu_backtrace+0x150/0x170 lib/nmi_backtrace.c:113) [<81b20218>] (nmi_cpu_backtrace) from [<81b204b8>] (nmi_trigger_cpumask_backtrace+0x130/0x1d8 lib/nmi_backtrace.c:62) r7:00000000 r6:82a0b150 r5:82a1c738 r4:ffffffff [<81b20388>] (nmi_trigger_cpumask_backtrace) from [<8022f0f4>] (arch_trigger_cpumask_backtrace+0x18/0x1c arch/arm/kernel/smp.c:851) r9:82a0b2f0 r8:00000001 r7:82a1ce00 r6:82cc5e2c r5:00007ed9 r4:00000048 [<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b28004>] (trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]) [<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b28004>] (__sys_info lib/sys_info.c:157 [inline]) [<8022f0dc>] (arch_trigger_cpumask_backtrace) from [<81b28004>] (sys_info+0x68/0xa8 lib/sys_info.c:165) [<81b27f9c>] (sys_info) from [<8038f83c>] (check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]) [<81b27f9c>] (sys_info) from [<8038f83c>] (watchdog+0x3a0/0x848 kernel/hung_task.c:561) r5:00007ed9 r4:0000000a [<8038f49c>] (watchdog) from [<80281740>] (kthread+0x11c/0x154 kernel/kthread.c:436) r10:00000000 r9:df819e60 r8:8310f880 r7:00000000 r6:8038f49c r5:83380000 r4:8387b640 [<80281624>] (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 r5:80281624 r4:8387b640 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 2821 Comm: pr/ttyAMA-1 Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline] PC is at _raw_spin_unlock_irqrestore+0x28/0x54 kernel/locking/spinlock.c:198 LR is at spin_unlock_irqrestore include/linux/spinlock.h:408 [inline] LR is at __uart_port_unlock_irqrestore include/linux/serial_core.h:616 [inline] LR is at pl011_console_device_unlock+0x20/0x24 drivers/tty/serial/amba-pl011.c:2668 pc : [<81b41678>] lr : [<80af4844>] psr: 60000113 sp : eb251ec8 ip : eb251ed8 fp : eb251ed4 r10: 82b5be2c r9 : 00000001 r8 : 00000000 r7 : 00000117 r6 : 82b5bd90 r5 : 00000000 r4 : 00000001 r3 : 00001ffb r2 : 00000000 r1 : 60000113 r0 : 846f0440 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 860c2dc0 DAC: 00000000 Call trace: [<81b41650>] (_raw_spin_unlock_irqrestore) from [<80af4844>] (spin_unlock_irqrestore include/linux/spinlock.h:408 [inline]) [<81b41650>] (_raw_spin_unlock_irqrestore) from [<80af4844>] (__uart_port_unlock_irqrestore include/linux/serial_core.h:616 [inline]) [<81b41650>] (_raw_spin_unlock_irqrestore) from [<80af4844>] (pl011_console_device_unlock+0x20/0x24 drivers/tty/serial/amba-pl011.c:2668) [<80af4824>] (pl011_console_device_unlock) from [<802ec160>] (nbcon_emit_one+0x88/0x100 kernel/printk/nbcon.c:1165) [<802ec0d8>] (nbcon_emit_one) from [<802ec3e0>] (nbcon_kthread_func+0x208/0x2ec kernel/printk/nbcon.c:1271) r6:82cc22ec r5:82b5bd90 r4:8410ee40 [<802ec1d8>] (nbcon_kthread_func) from [<80281740>] (kthread+0x11c/0x154 kernel/kthread.c:436) r10:00000000 r9:df8ddb38 r8:84c14f00 r7:82b5bd90 r6:802ec1d8 r5:8410ee40 r4:83e5b900 [<80281624>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137) Exception stack(0xeb251fb0 to 0xeb251ff8) 1fa0: 00000000 00000000 00000000 00000000 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80281624 r4:83e5b900