rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 GPs behind) idle=0b64/1/0x4000000000000000 softirq=12397/12417 fqs=0
	(t=10501 jiffies g=11077 q=1299 ncpus=2)
rcu: rcu_preempt kthread starved for 10502 jiffies! g11077 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:27200 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:2167
 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4667 Comm: syz.3.20 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline]
RIP: 0010:kasan_check_range+0xf/0x290 mm/kasan/generic.c:189
Code: 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 a4 01 00 00 41 57 41 56 <53> 49 89 f8 49 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1 e8 2f 41 81
RSP: 0018:ffffc90000007ba8 EFLAGS: 00000002
RAX: 00000000ffffff01 RBX: ffff8880b8e2a580 RCX: ffffffff81643c2e
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff8880b8e2a580
RBP: ffffc90000007c70 R08: dffffc0000000000 R09: fffffbfff215c44a
R10: fffffbfff215c44a R11: 1ffffffff215c449 R12: ffff8880b8e2a590
R13: ffff8880b8e2a588 R14: 1ffff110171c54b2 R15: 1ffff110171c54b1
FS:  0000555556d3f500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f663fff CR3: 00000000252b3000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
 atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:541 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
 do_raw_spin_lock+0x10e/0x280 kernel/locking/spinlock_debug.c:115
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:120 [inline]
 _raw_spin_lock_irq+0xab/0xe0 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1751 [inline]
 __hrtimer_run_queues+0x63a/0xd60 kernel/time/hrtimer.c:1811
 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e 8f 41 f7 48 89 df e8 e6 54 42 f7 e8 31 48 65 f7 fb bf 01 00 00 00 <e8> 76 cd 35 f7 65 8b 05 f7 84 e0 75 85 c0 74 02 5b c3 e8 44 96 de
RSP: 0018:ffffc90003a67b98 EFLAGS: 00000282
RAX: 4ecf13175c808300 RBX: ffff88802d934a00 RCX: 4ecf13175c808300
RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: 0000000000000001
RBP: ffff88802d934c98 R08: dffffc0000000000 R09: ffffed1005b26941
R10: ffffed1005b26941 R11: 1ffff11005b26940 R12: 1ffff11005b26993
R13: 0000000000000011 R14: dffffc0000000000 R15: 0000000000000000
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x1163/0x1350 kernel/signal.c:2874
 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: 0033:0x7f3c3ff8f749
Code: 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 01 48
RSP: 002b:00007ffe87b717f8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000030b77 RCX: 00007f3c3ff8f749
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000587b71aef
R10: 0000001b2ea20000 R11: 0000000000000246 R12: 00007f3c401e5fac
R13: 00007f3c401e5fa0 R14: ffffffffffffffff R15: 0000000000000004
 </TASK>
CPU: 1 PID: 4666 Comm: syz.5.33 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:copy_user_enhanced_fast_string+0x3/0x40 arch/x86/lib/copy_user_64.S:164
Code: 07 48 ff c6 48 ff c7 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
RSP: 0018:ffffc90003b57cc8 EFLAGS: 00040246
RAX: ffffffff84072901 RBX: 00000000000000c0 RCX: ffffffff84072987
RDX: 00000000000000c0 RSI: 00007ffed6436e68 RDI: ffffc90003b57d60
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff5200076afc4
R10: 0000000000000000 R11: 0000000000000010 R12: 00007fffffffef40
R13: 1ffff9200076affe R14: ffffc90003b57d60 R15: 00007ffed6436e68
FS:  0000555567ff6500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ed63fff CR3: 00000000739bc000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline]
 _copy_from_user+0xf4/0x170 lib/usercopy.c:23
 copy_from_user include/linux/uaccess.h:161 [inline]
 restore_sigcontext arch/x86/kernel/signal.c:92 [inline]
 __ia32_sys_rt_sigreturn+0x1e6/0x790 arch/x86/kernel/signal.c:675
 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: 0033:0x7fadd492b829
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007ffed6436e40 EFLAGS: 00000246 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007fadd4be5fa0 RCX: 00007fadd492b829
RDX: 00007ffed6436e40 RSI: 00007ffed6436f70 RDI: 0000000000000011
RBP: 00007fadd4a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fadd4be5fa0 R14: 00007fadd4be5fa0 R15: 0000000000000004
 </TASK>