rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P17078/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=168949, q=539 ncpus=2)
task:syz.4.2500      state:R  running task     stack:25552 pid:17078 tgid:17076 ppid:16338  flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5727
Code: c1 05 aa 11 9a 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc9000317f3a8 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff9200062fe77 RCX: 0000000000000001
RDX: 0000000000000001 RSI: ffffffff8b4cc800 RDI: ffffffff8bb08500
RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff28c5ad8
R10: ffffffff9462d6c7 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8ddb5ca0 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 rcu_read_lock include/linux/rcupdate.h:838 [inline]
 blk_cgroup_congested+0x35/0x270 block/blk-cgroup.c:2188
 __folio_throttle_swaprate+0xa8/0x2f0 mm/swapfile.c:3742
 folio_throttle_swaprate include/linux/swap.h:641 [inline]
 folio_prealloc mm/memory.c:1072 [inline]
 wp_page_copy mm/memory.c:3335 [inline]
 do_wp_page+0x1042/0x3430 mm/memory.c:3727
 handle_pte_fault mm/memory.c:5538 [inline]
 __handle_mm_fault+0x2468/0x5660 mm/memory.c:5665
 handle_mm_fault+0x44e/0x7b0 mm/memory.c:5833
 do_user_addr_fault+0x7a3/0x13f0 arch/x86/mm/fault.c:1389
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:rep_movs_alternative+0x4a/0x70 arch/x86/lib/copy_user_64.S:71
Code: 75 f1 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 <f3> a4 c3 cc cc cc cc 48 89 c8 48 c1 e9 03 83 e0 07 f3 48 a5 89 c1
RSP: 0018:ffffc9000317f958 EFLAGS: 00050206
RAX: 0000000000000001 RBX: 0000000000001000 RCX: 0000000000000e80
RDX: 0000000000000000 RSI: ffff888013236180 RDI: 0000000020992000
RBP: 0000000000001000 R08: 0000000000000000 R09: ffffed1002646dff
R10: ffff888013236fff R11: 0000000000000000 R12: 0000000000991b80
R13: ffffc9000317fd50 R14: ffff888013236000 R15: 0000000020991e80
 copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:131 [inline]
 copy_to_user_iter lib/iov_iter.c:25 [inline]
 iterate_iovec include/linux/iov_iter.h:51 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:247 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x4d2/0x1150 lib/iov_iter.c:185
 copy_page_to_iter lib/iov_iter.c:362 [inline]
 copy_page_to_iter+0xf1/0x180 lib/iov_iter.c:349
 process_vm_rw_pages mm/process_vm_access.c:45 [inline]
 process_vm_rw_single_vec mm/process_vm_access.c:118 [inline]
 process_vm_rw_core.constprop.0+0x5c9/0xa10 mm/process_vm_access.c:216
 process_vm_rw+0x301/0x360 mm/process_vm_access.c:284
 __do_sys_process_vm_readv mm/process_vm_access.c:296 [inline]
 __se_sys_process_vm_readv mm/process_vm_access.c:292 [inline]
 __x64_sys_process_vm_readv+0xe2/0x1c0 mm/process_vm_access.c:292
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f87eb5779f9
RSP: 002b:00007f87ec3a1048 EFLAGS: 00000246 ORIG_RAX: 0000000000000136
RAX: ffffffffffffffda RBX: 00007f87eb705f80 RCX: 00007f87eb5779f9
RDX: 0000000000000002 RSI: 0000000020008400 RDI: 000000000000005d
RBP: 00007f87eb5e58ee R08: 0000000000000286 R09: 0000000000000000
R10: 0000000020008640 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f87eb705f80 R15: 00007ffc8a960968
 </TASK>
rcu: rcu_preempt kthread starved for 10376 jiffies! g168949 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27680 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6621
 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2034
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2236
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111
sched: RT throttling activated