INFO: task syz.4.690:11919 blocked for more than 430 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.690       state:D stack:0     pid:11919 tgid:11919 ppid:11187  task_flags:0x40044c flags:0x00000002
Call Trace:
[<ffffffff86544f00>] context_switch kernel/sched/core.c:5325 [inline]
[<ffffffff86544f00>] __schedule+0x1042/0x4114 kernel/sched/core.c:6929
[<ffffffff86548096>] __schedule_loop kernel/sched/core.c:7011 [inline]
[<ffffffff86548096>] schedule+0xc4/0x35e kernel/sched/core.c:7026
[<ffffffff86548a18>] schedule_preempt_disabled+0x16/0x28 kernel/sched/core.c:7083
[<ffffffff86553d18>] rwsem_down_read_slowpath+0x58c/0x9f4 kernel/locking/rwsem.c:1086
[<ffffffff86554264>] __down_read_common kernel/locking/rwsem.c:1261 [inline]
[<ffffffff86554264>] __down_read kernel/locking/rwsem.c:1274 [inline]
[<ffffffff86554264>] down_read+0xe4/0x460 kernel/locking/rwsem.c:1539
[<ffffffff8015ed4e>] mmap_read_lock include/linux/mmap_lock.h:368 [inline]
[<ffffffff8015ed4e>] exit_mm kernel/exit.c:558 [inline]
[<ffffffff8015ed4e>] do_exit+0x6c2/0x28e4 kernel/exit.c:954
[<ffffffff801614d0>] do_group_exit+0xd4/0x26c kernel/exit.c:1107
[<ffffffff8019a8d0>] get_signal+0x2076/0x22f8 kernel/signal.c:3034
[<ffffffff80071698>] arch_do_signal_or_restart+0x100/0x1c4e arch/riscv/kernel/signal.c:534
[<ffffffff8653b846>] exit_to_user_mode_loop kernel/entry/common.c:40 [inline]
[<ffffffff8653b846>] exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
[<ffffffff8653b846>] irqentry_exit_to_user_mode+0x2cc/0x3ca kernel/entry/common.c:73
[<ffffffff8653ba52>] irqentry_exit+0x10e/0x194 kernel/entry/common.c:191
[<ffffffff8653a768>] do_page_fault+0x3e/0x56 arch/riscv/kernel/traps.c:432
[<ffffffff86563eae>] handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232
INFO: task syz.4.690:11923 blocked for more than 430 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.690       state:D stack:0     pid:11923 tgid:11919 ppid:11187  task_flags:0x40044c flags:0x00000002
Call Trace:
[<ffffffff86544f00>] context_switch kernel/sched/core.c:5325 [inline]
[<ffffffff86544f00>] __schedule+0x1042/0x4114 kernel/sched/core.c:6929
[<ffffffff86548096>] __schedule_loop kernel/sched/core.c:7011 [inline]
[<ffffffff86548096>] schedule+0xc4/0x35e kernel/sched/core.c:7026
[<ffffffff86548a18>] schedule_preempt_disabled+0x16/0x28 kernel/sched/core.c:7083
[<ffffffff86553d18>] rwsem_down_read_slowpath+0x58c/0x9f4 kernel/locking/rwsem.c:1086
[<ffffffff86554264>] __down_read_common kernel/locking/rwsem.c:1261 [inline]
[<ffffffff86554264>] __down_read kernel/locking/rwsem.c:1274 [inline]
[<ffffffff86554264>] down_read+0xe4/0x460 kernel/locking/rwsem.c:1539
[<ffffffff8015ed4e>] mmap_read_lock include/linux/mmap_lock.h:368 [inline]
[<ffffffff8015ed4e>] exit_mm kernel/exit.c:558 [inline]
[<ffffffff8015ed4e>] do_exit+0x6c2/0x28e4 kernel/exit.c:954
[<ffffffff801614d0>] do_group_exit+0xd4/0x26c kernel/exit.c:1107
[<ffffffff8019a8d0>] get_signal+0x2076/0x22f8 kernel/signal.c:3034
[<ffffffff80071cd0>] arch_do_signal_or_restart+0x738/0x1c4e arch/riscv/kernel/signal.c:534
[<ffffffff803c2f24>] exit_to_user_mode_loop+0x8a/0x142 kernel/entry/common.c:40
[<ffffffff8653a590>] exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
[<ffffffff8653a590>] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
[<ffffffff8653a590>] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
[<ffffffff8653a590>] do_trap_ecall_u+0x3f8/0x53a arch/riscv/kernel/traps.c:357
[<ffffffff86563eae>] handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232

Showing all locks held in the system:
1 lock held by khungtaskd/33:
 #0: ffffffff885df920 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2a/0x1a0 kernel/locking/lockdep.c:6771
2 locks held by getty/3163:
 #0: ffffaf801d2560a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3a/0x46 drivers/tty/tty_ldsem.c:340
 #1: ffff8f800008e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x3e4/0x12b6 drivers/tty/n_tty.c:2222
1 lock held by sshd/3186:
2 locks held by syz-executor/3188:
2 locks held by kworker/0:4/3815:
3 locks held by kworker/u8:9/8147:
 #0: ffffaf8018f35148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x848/0x1f3a kernel/workqueue.c:3238
 #1: ffff8f8009d87b70 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x870/0x1f3a kernel/workqueue.c:3238
 #2: ffffffff89abe228 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x22/0x2a net/core/rtnetlink.c:80
3 locks held by kworker/u8:6/9220:
3 locks held by kworker/u8:3/10131:
5 locks held by kworker/u8:7/10684:
3 locks held by kworker/u8:0/11190:
2 locks held by kworker/u8:10/11687:
1 lock held by syz.4.690/11919:
 #0: ffffaf801c0065d0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:368 [inline]
 #0: ffffaf801c0065d0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm kernel/exit.c:558 [inline]
 #0: ffffaf801c0065d0 (&mm->mmap_lock){++++}-{4:4}, at: do_exit+0x6c2/0x28e4 kernel/exit.c:954
3 locks held by syz.4.690/11922:
1 lock held by syz.4.690/11923:
 #0: ffffaf801c0065d0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:368 [inline]
 #0: ffffaf801c0065d0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm kernel/exit.c:558 [inline]
 #0: ffffaf801c0065d0 (&mm->mmap_lock){++++}-{4:4}, at: do_exit+0x6c2/0x28e4 kernel/exit.c:954
1 lock held by syz-executor/11949:
 #0: ffffffff89abe228 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x22/0x2a net/core/rtnetlink.c:80
1 lock held by dhcpcd-run-hook/12563:
1 lock held by kworker/u8:10/12564:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 33 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT 
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff8007a1a2>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:149
[<ffffffff8000329c>] show_stack+0x30/0x3c arch/riscv/kernel/stacktrace.c:155
[<ffffffff800609c8>] __dump_stack lib/dump_stack.c:94 [inline]
[<ffffffff800609c8>] dump_stack_lvl+0x12a/0x1a2 lib/dump_stack.c:120
[<ffffffff80060a5c>] dump_stack+0x1c/0x24 lib/dump_stack.c:129
[<ffffffff864fc02a>] nmi_cpu_backtrace+0x3b0/0x3b2 lib/nmi_backtrace.c:113
[<ffffffff864fc2e2>] nmi_trigger_cpumask_backtrace+0x2b6/0x45a lib/nmi_backtrace.c:62
[<ffffffff80087ede>] arch_trigger_cpumask_backtrace+0x2c/0x3e arch/riscv/kernel/smp.c:350
[<ffffffff8050735e>] trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
[<ffffffff8050735e>] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
[<ffffffff8050735e>] watchdog+0xf58/0x11ac kernel/hung_task.c:495
[<ffffffff801e8940>] kthread+0x39c/0x7d6 kernel/kthread.c:463
[<ffffffff80069a46>] ret_from_fork_kernel+0x2a/0xbc6 arch/riscv/kernel/process.c:228
[<ffffffff86563fde>] ret_from_fork_kernel_asm+0x16/0x18 arch/riscv/kernel/entry.S:363
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 3012 Comm: klogd Not tainted syzkaller #0 PREEMPT 
Hardware name: riscv-virtio,qemu (DT)
epc : __sanitizer_cov_trace_pc+0x0/0x78 kernel/kcov.c:210
 ra : __virt_to_phys+0x24/0x262 arch/riscv/mm/physaddr.c:14
epc : ffffffff80504f34 ra : ffffffff800a5a68 sp : ffff8f8003ca7450
 gp : ffffffff89ede020 tp : ffffaf8019070000 t0 : fffff5ef06111000
 t1 : 0000000000000001 t2 : 000000001c66184e s0 : ffff8f8003ca7490
 s1 : ffffaf8034b47600 a0 : ffffaf8034b47600 a1 : ffffaf8034b47600
 a2 : ffffffff80b57ae4 a3 : 0000000000000001 a4 : 0000020000000000
 a5 : 0000220000000000 a6 : 0000000000000003 a7 : ffffffff80aa6b5a
 s2 : ffff8d8000000000 s3 : ffffffff88030340 s4 : ffffffff80b57ae4
 s5 : ffffaf80146ccb40 s6 : ffffaf8034b47600 s7 : 00000000000000f5
 s8 : ffffffff88030378 s9 : ffffffff88030338 s10: ffffffff88030340
 s11: ffffaf8034b47600 t3 : d97c821500000000 t4 : 0000000000000000
 t5 : 0000000000000000 t6 : 0000000000000002 ssp : 0000000000000000
status: 0000000200000120 badaddr: 0000000000000000 cause: 8000000000000001
[<ffffffff80504f34>] __sanitizer_cov_trace_pc+0x0/0x78 kernel/kcov.c:442
[<ffffffff80ab1a9e>] virt_to_folio include/linux/mm.h:1252 [inline]
[<ffffffff80ab1a9e>] virt_to_slab mm/slab.h:191 [inline]
[<ffffffff80ab1a9e>] ___cache_free+0x64/0x1dc mm/slub.c:6700
[<ffffffff80b57aee>] qlink_free mm/kasan/quarantine.c:163 [inline]
[<ffffffff80b57aee>] qlist_free_all+0x76/0x168 mm/kasan/quarantine.c:179
[<ffffffff80b5819c>] kasan_quarantine_reduce+0x158/0x1ba mm/kasan/quarantine.c:286
[<ffffffff80b53ec8>] __kasan_slab_alloc+0x5c/0x82 mm/kasan/common.c:352
[<ffffffff80aa8462>] kasan_slab_alloc include/linux/kasan.h:252 [inline]
[<ffffffff80aa8462>] slab_post_alloc_hook mm/slub.c:4974 [inline]
[<ffffffff80aa8462>] slab_alloc_node mm/slub.c:5284 [inline]
[<ffffffff80aa8462>] kmem_cache_alloc_node_noprof+0x1f6/0x762 mm/slub.c:5336
[<ffffffff852109a4>] __alloc_skb+0x33a/0x438 net/core/skbuff.c:660
[<ffffffff8522575a>] alloc_skb include/linux/skbuff.h:1383 [inline]
[<ffffffff8522575a>] alloc_skb_with_frags+0xe2/0x838 net/core/skbuff.c:6671
[<ffffffff851e6212>] sock_alloc_send_pskb+0x6e2/0x82a net/core/sock.c:2965
[<ffffffff85d36546>] unix_dgram_sendmsg+0x370/0x1586 net/unix/af_unix.c:2153
[<ffffffff851d04be>] sock_sendmsg_nosec net/socket.c:727 [inline]
[<ffffffff851d04be>] __sock_sendmsg+0xcc/0x160 net/socket.c:742
[<ffffffff851d972a>] __sys_sendto+0x27a/0x34e net/socket.c:2244
[<ffffffff851d98be>] __do_sys_sendto net/socket.c:2251 [inline]
[<ffffffff851d98be>] __se_sys_sendto net/socket.c:2247 [inline]
[<ffffffff851d98be>] __riscv_sys_sendto+0xc0/0x158 net/socket.c:2247
[<ffffffff80077d1c>] syscall_handler+0x94/0x118 arch/riscv/include/asm/syscall.h:112
[<ffffffff8653a536>] do_trap_ecall_u+0x39e/0x53a arch/riscv/kernel/traps.c:343
[<ffffffff86563eae>] handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232