rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7684/1:b..l P47/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=42265, q=274 ncpus=2)
task:kworker/u8:3    state:R  running task     stack:21248 pid:47    tgid:47    ppid:2      flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 preempt_schedule_notrace+0x100/0x140 kernel/sched/core.c:6801
 preempt_schedule_notrace_thunk+0x1a/0x30 arch/x86/entry/thunk.S:13
 rcu_is_watching+0x7e/0xb0 kernel/rcu/tree.c:727
 rcu_read_unlock include/linux/rcupdate.h:867 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0x207/0x610 net/batman-adv/network-coding.c:719
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
task:syz.2.414       state:R  running task     stack:24544 pid:7684  tgid:7682  ppid:5230   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5763
Code: 2b 00 74 08 4c 89 f7 e8 0a 0e 8b 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90002cfef80 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff9200059fdfc RCX: 4b8f82e09ef10300
RDX: dffffc0000000000 RSI: ffffffff8c0ae720 RDI: ffffffff8c606920
RBP: ffffc90002cff0c8 R08: ffffffff93726807 R09: 1ffffffff26e4d00
R10: dffffc0000000000 R11: fffffbfff26e4d01 R12: 1ffff9200059fdf8
R13: dffffc0000000000 R14: ffffc90002cfefe0 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 rcu_read_lock include/linux/rcupdate.h:838 [inline]
 __pte_offset_map+0x9e/0x380 mm/pgtable-generic.c:287
 __pte_offset_map_lock+0xc7/0x300 mm/pgtable-generic.c:371
 pte_offset_map_lock include/linux/mm.h:2985 [inline]
 finish_fault+0x79d/0x1480 mm/memory.c:4908
 do_shared_fault mm/memory.c:5141 [inline]
 do_fault mm/memory.c:5195 [inline]
 do_pte_missing mm/memory.c:3947 [inline]
 handle_pte_fault+0x1e66/0x6eb0 mm/memory.c:5522
 __handle_mm_fault mm/memory.c:5665 [inline]
 handle_mm_fault+0x1029/0x1980 mm/memory.c:5833
 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline]
RIP: 0010:raw_copy_to_user arch/x86/include/asm/uaccess_64.h:131 [inline]
RIP: 0010:_copy_to_user+0x81/0xb0 lib/usercopy.c:46
Code: fc 4c 89 f0 4c 01 e0 78 3b 4c 39 f0 72 36 e8 16 72 e3 fc 4c 89 ff 44 89 e6 e8 eb ac 4a fd 0f 01 cb 4c 89 e1 4c 89 fe 4c 89 f7 <f3> a4 0f 1f 00 49 89 cc 0f 01 ca 4c 89 e0 5b 41 5c 41 5e 41 5f e9
RSP: 0018:ffffc90002cffad8 EFLAGS: 00050256
RAX: ffffffff84b01101 RBX: 0000000020061040 RCX: 0000000000000040
RDX: 0000000000000000 RSI: ffffc90002cffb60 RDI: 0000000020061000
RBP: ffffc90002cffc10 R08: ffffc90002cffb9f R09: 1ffff9200059ff73
R10: dffffc0000000000 R11: fffff5200059ff74 R12: 0000000000000040
R13: 000000000002d580 R14: 0000000020061000 R15: ffffc90002cffb60
 copy_to_user include/linux/uaccess.h:191 [inline]
 rng_dev_read+0x3be/0x6d0 drivers/char/hw_random/core.c:251
 do_loop_readv_writev fs/read_write.c:761 [inline]
 vfs_readv+0x6c4/0xa90 fs/read_write.c:934
 do_preadv fs/read_write.c:1049 [inline]
 __do_sys_preadv fs/read_write.c:1099 [inline]
 __se_sys_preadv fs/read_write.c:1094 [inline]
 __x64_sys_preadv+0x1c7/0x2d0 fs/read_write.c:1094
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe4a2d77299
RSP: 002b:00007fe4a3b83048 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00007fe4a2f05f80 RCX: 00007fe4a2d77299
RDX: 0000000000000001 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 00007fe4a2de48e6 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fe4a2f05f80 R15: 00007fff631e7588
 </TASK>
rcu: rcu_preempt kthread starved for 10210 jiffies! g42265 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:25232 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.10.0-syzkaller-12710-g3a7e02c040b1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline]
RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112
Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 40 d7 03 00 48 f7 00 08 00 00 00 75 10 eb 07 0f 00 2d b5 c0 b4 00 f3 0f 1e fa fb f4 <fa> e9 f4 e4 3a 00 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90
RSP: 0018:ffffffff8e607ca8 EFLAGS: 00000246
RAX: ffffffff8e694680 RBX: ffff88801ce98864 RCX: 00000000000db779
RDX: 0000000000000001 RSI: ffff88801ce98800 RDI: ffff88801ce98864
RBP: 000000000003a6b8 R08: ffff8880b9237c7b R09: 1ffff11017246f8f
R10: dffffc0000000000 R11: ffffffff8bb557c0 R12: ffff88801bfe0800
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8f0d9de0
FS:  0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007febedda1924 CR3: 000000002e6b8000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:702
 cpuidle_enter_state+0x114/0x480 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:388
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:230 [inline]
 do_idle+0x375/0x5d0 kernel/sched/idle.c:326
 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:424
 rest_init+0x2dc/0x300 init/main.c:747
 start_kernel+0x47a/0x500 init/main.c:1103
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:488
 common_startup_64+0x13e/0x147
 </TASK>