rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 0, t=10502 jiffies, g=71709, q=106)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295014044-4295003542), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor.4  R  running task    26520 20003  10439 0x00004000
Call Trace:
 <IRQ>
 sched_show_task kernel/sched/core.c:5952 [inline]
 sched_show_task.cold+0x2ee/0x35d kernel/sched/core.c:5927
 print_other_cpu_stall kernel/rcu/tree_stall.h:430 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:558 [inline]
 rcu_pending kernel/rcu/tree.c:3225 [inline]
 rcu_sched_clock_irq.cold+0xbee/0xd22 kernel/rcu/tree.c:2296
 update_process_times+0x2d/0x70 kernel/time/timer.c:1727
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:171
 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1314
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1641
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1119 [inline]
 smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1144
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:wb_find_current include/linux/backing-dev.h:279 [inline]
RIP: 0010:wb_get_create_current include/linux/backing-dev.h:308 [inline]
RIP: 0010:balance_dirty_pages_ratelimited+0x7e1/0x1e00 mm/page-writeback.c:1876
Code: 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 43 14 00 00 48 b8 00 00 00 00 00 fc ff df 49 8b 5d 20 <48> 8d bb 28 01 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 6d 14
RSP: 0018:ffffc90007a47400 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffff88809ec0a000 RCX: ffffc90011a32000
RDX: 1ffff11011e0bd04 RSI: ffffffff8197b4e4 RDI: ffff88808f05e820
RBP: ffffc90007a474d0 R08: ffff888044672500 R09: ffffed1015d07084
R10: ffffed1015d07083 R11: ffff8880ae83841b R12: ffff8880a124c000
R13: ffff88808f05e800 R14: 0000000000000000 R15: ffffc90007a474a8
 generic_perform_write+0x364/0x540 mm/filemap.c:3323
 ext4_buffered_write_iter+0x1fe/0x460 fs/ext4/file.c:270
 ext4_file_write_iter+0x1fe/0x14e0 fs/ext4/file.c:642
 call_write_iter include/linux/fs.h:1901 [inline]
 do_iter_readv_writev+0x5f8/0x8f0 fs/read_write.c:693
 do_iter_write fs/read_write.c:998 [inline]
 do_iter_write+0x184/0x610 fs/read_write.c:979
 vfs_iter_write+0x77/0xb0 fs/read_write.c:1039
 iter_file_splice_write+0x717/0xc10 fs/splice.c:760
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0x123/0x190 fs/splice.c:1037
 splice_direct_to_actor+0x3b4/0xa30 fs/splice.c:992
 do_splice_direct+0x1da/0x2a0 fs/splice.c:1080
 do_sendfile+0x597/0xd00 fs/read_write.c:1520
 __do_sys_sendfile64 fs/read_write.c:1575 [inline]
 __se_sys_sendfile64 fs/read_write.c:1567 [inline]
 __x64_sys_sendfile64+0x15a/0x220 fs/read_write.c:1567
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c6c9
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fa9d373fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fa9d37406d4 RCX: 000000000045c6c9
RDX: 00000000200001c0 RSI: 0000000000000004 RDI: 0000000000000004
RBP: 000000000076c070 R08: 0000000000000000 R09: 0000000000000000
R10: 00008080fffffffe R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000008cb R14: 00000000004cb58f R15: 000000000076c07c
rcu: rcu_preempt kthread starved for 10502 jiffies! g71709 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29120    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3380 [inline]
 __schedule+0x934/0x1f90 kernel/sched/core.c:4080
 schedule+0xdc/0x2b0 kernel/sched/core.c:4154
 schedule_timeout+0x36e/0x8c0 kernel/time/timer.c:1896
 rcu_gp_fqs_loop kernel/rcu/tree.c:1673 [inline]
 rcu_gp_kthread+0xa02/0x1b00 kernel/rcu/tree.c:1836
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352