INFO: task syz.0.413:5418 blocked for more than 430 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.413       state:D stack:0     pid:5418  tgid:5416  ppid:3242   task_flags:0x400640 flags:0x00000002
Call Trace:
[<ffffffff8639c964>] context_switch kernel/sched/core.c:5260 [inline]
[<ffffffff8639c964>] __schedule+0xf10/0x4098 kernel/sched/core.c:6867
[<ffffffff8639fba0>] __schedule_loop kernel/sched/core.c:6949 [inline]
[<ffffffff8639fba0>] schedule+0xb4/0x334 kernel/sched/core.c:6964
[<ffffffff863b5a06>] schedule_timeout+0x1c2/0x2a0 kernel/time/sleep_timeout.c:75
[<ffffffff863a1750>] do_wait_for_common kernel/sched/completion.c:100 [inline]
[<ffffffff863a1750>] __wait_for_common+0x1c0/0x3e8 kernel/sched/completion.c:121
[<ffffffff863a1a52>] wait_for_common kernel/sched/completion.c:132 [inline]
[<ffffffff863a1a52>] wait_for_completion_state+0x1a/0x2c kernel/sched/completion.c:269
[<ffffffff80e45f56>] coredump_wait fs/coredump.c:534 [inline]
[<ffffffff80e45f56>] vfs_coredump+0x702/0x5588 fs/coredump.c:1196
[<ffffffff80195264>] get_signal+0x1fe8/0x224c kernel/signal.c:3019
[<ffffffff80071b44>] arch_do_signal_or_restart+0xf4/0x1ddc arch/riscv/kernel/signal.c:534
[<ffffffff8639337c>] __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
[<ffffffff8639337c>] exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
[<ffffffff8639337c>] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
[<ffffffff8639337c>] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
[<ffffffff8639337c>] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
[<ffffffff8639337c>] irqentry_exit+0x3f0/0xb04 kernel/entry/common.c:196
[<ffffffff8639211a>] do_page_fault+0x3e/0x58 arch/riscv/kernel/traps.c:434
[<ffffffff863bb61e>] handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232

Showing all locks held in the system:
1 lock held by khungtaskd/33:
 #0: ffffffff885ec160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2a/0x1a8 kernel/locking/lockdep.c:6771
1 lock held by klogd/3015:
2 locks held by getty/3178:
 #0: ffffaf801da1b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3a/0x48 drivers/tty/tty_ldsem.c:340
 #1: ffff8f800008e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x3be/0x1324 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/3229:
4 locks held by syz-executor/3243:
4 locks held by kworker/u8:1/3257:
4 locks held by kworker/u8:7/3809:
3 locks held by kworker/u8:0/4268:
2 locks held by kworker/1:4/5232:
2 locks held by syz.0.413/5417:
1 lock held by syz-executor/5437:
3 locks held by kworker/u8:5/5772:
 #0: ffffaf801d64e948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x814/0x1e14 kernel/workqueue.c:3232
 #1: ffff8f8009b07b70 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x83c/0x1e14 kernel/workqueue.c:3232
 #2: ffffffff89b593e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x22/0x2c net/core/rtnetlink.c:80

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 33 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT 
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff8007afc2>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:149
[<ffffffff800032f8>] show_stack+0x30/0x3c arch/riscv/kernel/stacktrace.c:155
[<ffffffff80060e34>] __dump_stack lib/dump_stack.c:94 [inline]
[<ffffffff80060e34>] dump_stack_lvl+0x114/0x1ac lib/dump_stack.c:120
[<ffffffff80060ee8>] dump_stack+0x1c/0x28 lib/dump_stack.c:129
[<ffffffff863532a6>] nmi_cpu_backtrace+0x25e/0x3b0 lib/nmi_backtrace.c:113
[<ffffffff86353696>] nmi_trigger_cpumask_backtrace+0x29e/0x460 lib/nmi_backtrace.c:62
[<ffffffff8008885c>] arch_trigger_cpumask_backtrace+0x2c/0x3c arch/riscv/kernel/smp.c:350
[<ffffffff86367c9c>] trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
[<ffffffff86367c9c>] __sys_info lib/sys_info.c:157 [inline]
[<ffffffff86367c9c>] sys_info+0x20c/0x254 lib/sys_info.c:165
[<ffffffff80506688>] check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
[<ffffffff80506688>] watchdog+0xb44/0x1184 kernel/hung_task.c:515
[<ffffffff801e2fcc>] kthread+0x37c/0x778 kernel/kthread.c:463
[<ffffffff80069946>] ret_from_fork_kernel+0x2a/0xbbc arch/riscv/kernel/process.c:228
[<ffffffff863bb74e>] ret_from_fork_kernel_asm+0x16/0x18 arch/riscv/kernel/entry.S:363
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 3011 Comm: syslogd Not tainted syzkaller #0 PREEMPT 
Hardware name: riscv-virtio,qemu (DT)
epc : syscall_enter_from_user_mode_work include/linux/entry-common.h:75 [inline]
epc : syscall_enter_from_user_mode include/linux/entry-common.h:109 [inline]
epc : do_trap_ecall_u+0x64/0x58c arch/riscv/kernel/traps.c:338
 ra : syscall_enter_from_user_mode include/linux/entry-common.h:108 [inline]
 ra : do_trap_ecall_u+0x60/0x58c arch/riscv/kernel/traps.c:338
epc : ffffffff8639189c ra : ffffffff86391898 sp : ffff8f8003eb7e90
 gp : ffffffff89f9df20 tp : ffffaf8018d8b500 t0 : ffffffff86806d10
 t1 : ffffffff8007a568 t2 : ffffffff86806d68 s0 : ffff8f8003eb7ee0
 s1 : ffff8f8003eb7ee0 a0 : 0000000000000001 a1 : 0000000000000000
 a2 : 0000000000000000 a3 : 0000000000000001 a4 : 0000000000001000
 a5 : 0000000000014e93 a6 : 0000000000000003 a7 : 0000000041b58ab3
 s2 : 00007fff7fba8560 s3 : ffffffff863bb61e s4 : 000000000000003f
 s5 : 00007fff7fa5cc20 s6 : 00007fff7fd2ffe0 s7 : 000000000000000a
 s8 : 000055559a287a50 s9 : 000000000000006b s10: 00007fff7fd2ffd8
 s11: 0000000000000001 t3 : ffffffff87d89ca8 t4 : ffffffffffffffff
 t5 : 0000000000000053 t6 : 0000000000000065 ssp : 0000000000000000
status: 0000000200000120 badaddr: 0000000000000000 cause: 8000000000000001
[<ffffffff8639189c>] arch_local_irq_enable arch/riscv/include/asm/irqflags.h:21 [inline]
[<ffffffff8639189c>] syscall_enter_from_user_mode include/linux/entry-common.h:108 [inline]
[<ffffffff8639189c>] do_trap_ecall_u+0x64/0x58c arch/riscv/kernel/traps.c:338
[<ffffffff863bb61e>] handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232