rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4469/1:b..l
	(detected by 0, t=10502 jiffies, g=11817, q=364 ncpus=2)
task:udevd           state:R  running task     stack:24544 pid:4469  ppid:3637   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5710
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90004967340 EFLAGS: 00000206
RAX: 86fb1d6e3e991900 RBX: ffff88807c298000 RCX: 86fb1d6e3e991900
RDX: ffff88807c298000 RSI: ffffffff8a6c1780 RDI: ffffffff8abef920
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff2119049
R10: fffffbfff2119049 R11: 1ffffffff2119048 R12: 0000000000000003
R13: 0000000000000246 R14: ffffffff8c953b68 R15: ffff88807c298b58
 lock_is_held include/linux/lockdep.h:283 [inline]
 task_css include/linux/cgroup.h:509 [inline]
 blkcg_css+0xa4/0x1c0 block/blk-cgroup.c:77
 blk_cgroup_congested+0xba/0x220 block/blk-cgroup.c:2013
 __cgroup_throttle_swaprate+0x6d/0x1a0 mm/swapfile.c:3671
 cgroup_throttle_swaprate include/linux/swap.h:672 [inline]
 do_anonymous_page mm/memory.c:4197 [inline]
 handle_pte_fault mm/memory.c:5029 [inline]
 __handle_mm_fault mm/memory.c:5173 [inline]
 handle_mm_fault+0x2c3f/0x3e60 mm/memory.c:5294
 do_user_addr_fault+0x51f/0xb10 arch/x86/mm/fault.c:1340
 handle_page_fault arch/x86/mm/fault.c:1431 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1487
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0010:copy_user_enhanced_fast_string+0xa/0x40 arch/x86/lib/copy_user_64.S:166
Code: ff c9 75 f2 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 20 0f 01 cb 83 fa 40 72 38 89 d1 <f3> a4 31 c0 0f 01 ca c3 89 ca eb 0a 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900049677b8 EFLAGS: 00050206
RAX: ffffffff8404df01 RBX: 0000000000001000 RCX: 0000000000001000
RDX: 0000000000001000 RSI: ffff8880555f9000 RDI: 00007f475e790000
RBP: ffffc90004967918 R08: dffffc0000000000 R09: ffffed100aabf400
R10: 0000000000000000 R11: 0000000000000200 R12: 1ffff9200092cfb7
R13: 00007f475e790000 R14: ffff8880555f9000 R15: 00007fffffffe000
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline]
 copyout lib/iov_iter.c:170 [inline]
 _copy_to_iter+0x2b6/0x1030 lib/iov_iter.c:527
 copy_page_to_iter+0xac/0x170 lib/iov_iter.c:725
 copy_folio_to_iter include/linux/uio.h:172 [inline]
 filemap_read+0x277e/0x2f80 mm/filemap.c:2819
 blkdev_read_iter+0x42d/0x570 block/fops.c:668
 call_read_iter include/linux/fs.h:2259 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x434/0x920 fs/read_write.c:470
 ksys_read+0x143/0x240 fs/read_write.c:613
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f475e0a7407
RSP: 002b:00007ffe5e7de770 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f475e7bb880 RCX: 00007f475e0a7407
RDX: 0000000000040000 RSI: 00007f475e753000 RDI: 0000000000000009
RBP: 0000560fe1346050 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 0000560fe134c8e8 R15: 00007f475e8e239c
 </TASK>
rcu: rcu_preempt kthread starved for 10546 jiffies! g11817 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:27840 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4729 Comm: syz.1.66 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:135 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x25d/0x290 mm/kasan/generic.c:189
Code: 04 eb 0c 4f 8d 4c 19 05 eb 05 4f 8d 4c 19 06 4d 89 ce 4d 85 c9 0f 84 5c ff ff ff 4c 8d 4c 3e ff 4d 89 ca 49 c1 ea 03 4d 01 c2 <4d> 39 d6 75 11 41 83 e1 07 4d 0f be 02 4d 39 c1 0f 8c 37 ff ff ff
RSP: 0018:ffffc90004107a60 EFLAGS: 00000082
RAX: 00000000ffffff01 RBX: ffffffffffffffff RCX: ffffffff8164462d
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90004107ac0
RBP: ffffc90004107b40 R08: dffffc0000000000 R09: ffffc90004107ac3
R10: fffff52000820f58 R11: 1ffff92000820f58 R12: ffff8880548a5c90
R13: ffff8880548a5c88 R14: fffff52000820f58 R15: dffffc0000000001
FS:  00007f36525d56c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5ab41156c0 CR3: 0000000026623000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
 atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:542 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
 do_raw_spin_lock+0x11d/0x280 kernel/locking/spinlock_debug.c:115
 spin_lock include/linux/spinlock.h:351 [inline]
 dequeue_signal+0x1cd/0x4b0 kernel/signal.c:705
 get_signal+0x547/0x1350 kernel/signal.c:2751
 arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f365438f747
Code: ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89
RSP: 002b:00007f36525d50e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f36545e6188 RCX: 00007f365438f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f36545e6188
RBP: 00007f36545e6180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f36545e6218 R14: 00007ffdbd55be20 R15: 00007ffdbd55bf08
 </TASK>