rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=119/1/0x4000000000000002 softirq=34312/34312 fqs=0 
	(detected by 1, t=10506 jiffies, g=39653, q=4546)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15975 Comm: syz.1.5590 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:set_preempt_need_resched arch/x86/include/asm/preempt.h:61 [inline]
RIP: 0010:rcu_read_unlock_special+0x264/0x480 kernel/rcu/tree_plugin.h:660
Code: 89 74 24 08 4c 8b 74 24 10 45 89 f5 41 c1 ed 09 65 4c 8b 3d 0e 10 9e 7e 4c 89 ff be 08 00 00 00 e8 91 d6 57 00 f0 41 80 0f 08 <65> 81 25 f9 0f 9e 7e ff ff ff 7f 45 08 e5 41 f6 c5 01 49 bd 00 00
RSP: 0000:ffffc90003db72a0 EFLAGS: 00000006
RAX: 0000000000000001 RBX: 1ffff920007b6e58 RCX: ffffffff81645fbf
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88807d05bb80
RBP: ffffc90003db7380 R08: dffffc0000000000 R09: ffffed100fa0b771
R10: ffffed100fa0b771 R11: 1ffff1100fa0b770 R12: ffffffff8c120c00
R13: 0000000000000000 R14: 0000000000000046 R15: ffff88807d05bb80
FS:  0000555559f47500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff23cfd7000 CR3: 00000000230dc000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 __perf_event_output kernel/events/core.c:7813 [inline]
 perf_event_output_forward+0x216/0x280 kernel/events/core.c:7822
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_tp_event+0x32c/0xb50 kernel/events/core.c:10047
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021
 perf_trace_preemptirq_template+0x2be/0x380 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 ed 11 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0000:ffffc90003db7a00 EFLAGS: 00000206
RAX: 6e4dfdcece8b5600 RBX: 1ffff920007b6f44 RCX: 6e4dfdcece8b5600
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800
RBP: ffffc90003db7ad0 R08: dffffc0000000000 R09: fffffbfff1ff5419
R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: ffffffff8c120c00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 __unlock_page_memcg+0xea/0x100 mm/memcontrol.c:2093
 wp_page_copy+0xeb2/0x1fd0 mm/memory.c:3148
 handle_pte_fault mm/memory.c:4668 [inline]
 __handle_mm_fault mm/memory.c:4785 [inline]
 handle_mm_fault+0x1ec7/0x43b0 mm/memory.c:4883
 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357
 handle_page_fault arch/x86/mm/fault.c:1445 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x7ff23cc562e8
Code: 80 3d 3b 0d 38 00 00 89 7c 24 0c 88 54 24 10 48 89 74 24 28 0f 85 c8 09 00 00 80 3d 06 44 eb 00 00 48 89 f5 41 89 d4 41 89 cd <c6> 05 11 0d 38 00 01 0f 85 23 04 00 00 80 3d d4 43 eb 00 00 0f 85
RSP: 002b:00007ffe3e5aac30 EFLAGS: 00010246
RAX: 00007ff23cfdafa0 RBX: 0000000000095199 RCX: 0000000000000000
RDX: 00000000fffffc03 RSI: 00007ff23cfdb038 RDI: 0000000000000000
RBP: 00007ff23cfdb038 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 00000000fffffc03
R13: 0000000000000000 R14: 00007ffe3e5aaca8 R15: 00007ffe3e5aae00
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g39653 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=38471
rcu: rcu_preempt kthread starved for 10506 jiffies! g39653 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27744 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </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: 15975 Comm: syz.1.5590 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:227 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x32/0x80 kernel/kcov.c:293
Code: 44 a0 8a 7e 65 8b 15 45 a0 8a 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 5b 83 b9 34 16 00 00 00 74 52 8b 91 10 16 00 00 <83> fa 03 75 47 48 8b 91 18 16 00 00 44 8b 89 14 16 00 00 49 c1 e1
RSP: 0000:ffffc90003db7900 EFLAGS: 00000046
RAX: ffffffff817dec0b RBX: 0000000000000000 RCX: ffff88807d05bb80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000555559f47500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff23cfd7000 CR3: 00000000230dc000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 trace_hardirqs_off_finish+0x1b/0x1f0 kernel/trace/trace_preemptirq.c:63
 irqentry_enter+0x33/0x50 kernel/entry/common.c:384
 sysvec_irq_work+0xa/0xc0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 ed 11 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0000:ffffc90003db7a00 EFLAGS: 00000206
RAX: 6e4dfdcece8b5600 RBX: 1ffff920007b6f44 RCX: 6e4dfdcece8b5600
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800
RBP: ffffc90003db7ad0 R08: dffffc0000000000 R09: fffffbfff1ff5419
R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: ffffffff8c120c00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 __unlock_page_memcg+0xea/0x100 mm/memcontrol.c:2093
 wp_page_copy+0xeb2/0x1fd0 mm/memory.c:3148
 handle_pte_fault mm/memory.c:4668 [inline]
 __handle_mm_fault mm/memory.c:4785 [inline]
 handle_mm_fault+0x1ec7/0x43b0 mm/memory.c:4883
 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357
 handle_page_fault arch/x86/mm/fault.c:1445 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x7ff23cc562e8
Code: 80 3d 3b 0d 38 00 00 89 7c 24 0c 88 54 24 10 48 89 74 24 28 0f 85 c8 09 00 00 80 3d 06 44 eb 00 00 48 89 f5 41 89 d4 41 89 cd <c6> 05 11 0d 38 00 01 0f 85 23 04 00 00 80 3d d4 43 eb 00 00 0f 85
RSP: 002b:00007ffe3e5aac30 EFLAGS: 00010246
RAX: 00007ff23cfdafa0 RBX: 0000000000095199 RCX: 0000000000000000
RDX: 00000000fffffc03 RSI: 00007ff23cfdb038 RDI: 0000000000000000
RBP: 00007ff23cfdb038 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 00000000fffffc03
R13: 0000000000000000 R14: 00007ffe3e5aaca8 R15: 00007ffe3e5aae00
 </TASK>