rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=d4b/1/0x4000000000000000 softirq=32556/32556 fqs=0 
	(detected by 1, t=10502 jiffies, g=49185, q=292)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10095 Comm: syz.0.2776 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:226 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x4/0x80 kernel/kcov.c:300
Code: 77 22 89 ff 89 f6 4a c7 44 02 08 05 00 00 00 4a 89 7c 02 10 4a 89 74 02 18 4a 89 44 02 20 48 ff c1 48 89 0a c3 90 48 8b 04 24 <65> 48 8b 0d 84 a1 8a 7e 65 8b 15 85 a1 8a 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc9000cc16c30 EFLAGS: 00000046
RAX: ffffffff81010d1f RBX: ffff8880b9035120 RCX: ffff888025c91dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffc9000cc16da0
R10: fffff52001982dbb R11: 1ffff92001982db4 R12: dffffc0000000000
R13: ffffc9000cc16e06 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33a63fff CR3: 0000000074784000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 user_mode arch/x86/include/asm/ptrace.h:136 [inline]
 perf_misc_flags+0x13f/0x1b0 arch/x86/events/core.c:2970
 perf_prepare_sample+0x132/0x1cb0 kernel/events/core.c:7622
 __perf_event_output kernel/events/core.c:7802 [inline]
 perf_event_output_forward+0x146/0x280 kernel/events/core.c:7822
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_swevent_overflow kernel/events/core.c:9591 [inline]
 perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629
 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 ad 13 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: 0018:ffffc9000cc17420 EFLAGS: 00000206
RAX: 0d7e13e3f8ad8e00 RBX: 1ffff92001982e88 RCX: 0d7e13e3f8ad8e00
RDX: dffffc0000000000 RSI: ffffffff8a0b1820 RDI: ffffffff8a59a4c0
RBP: ffffc9000cc174f0 R08: dffffc0000000000 R09: fffffbfff1ff7a19
R10: fffffbfff1ff7a19 R11: 1ffffffff1ff7a18 R12: ffffffff8c120b00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:771 [inline]
 __unlock_page_memcg+0xea/0x100 mm/memcontrol.c:2093
 zap_pte_range mm/memory.c:1384 [inline]
 zap_pmd_range mm/memory.c:1505 [inline]
 zap_pud_range mm/memory.c:1534 [inline]
 zap_p4d_range mm/memory.c:1555 [inline]
 unmap_page_range+0xfbc/0x2520 mm/memory.c:1576
 unmap_vmas+0x11b/0x230 mm/memory.c:1653
 exit_mmap+0x38f/0x5f0 mm/mmap.c:3216
 __mmput+0x115/0x3b0 kernel/fork.c:1127
 exit_mm+0x567/0x6c0 kernel/exit.c:550
 do_exit+0x5a1/0x20a0 kernel/exit.c:870
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 get_signal+0x6ca/0x12c0 kernel/signal.c:2900
 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa915e4dec9
Code: Unable to access opcode bytes at RIP 0x7fa915e4de9f.
RSP: 002b:00007fa9154bd0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fa9160a4fa8 RCX: 00007fa915e4dec9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fa9160a4fa8
RBP: 00007fa9160a4fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa9160a5038 R14: 00007fffec2879e0 R15: 00007fffec287ac8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g49185 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=18088
rcu: rcu_preempt kthread starved for 10502 jiffies! g49185 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:27008 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: 10095 Comm: syz.0.2776 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:hlock_class kernel/locking/lockdep.c:197 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4711 [inline]
RIP: 0010:__lock_acquire+0x91e/0x7c60 kernel/locking/lockdep.c:4962
Code: 89 c6 41 81 e6 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 c0 d0 fb 8f be 08 00 00 00 e8 7a 2d 60 00 4c 0f a3 35 42 ca 9f 0e <73> 1a 4b 8d 04 76 c1 e0 06 4c 8d b0 80 4f 94 8f 49 b8 00 00 00 00
RSP: 0018:ffffc9000cc16860 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff815c0676
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffbd0c0
RBP: ffffc9000cc16ab0 R08: dffffc0000000000 R09: fffffbfff1ff7a19
R10: fffffbfff1ff7a19 R11: 1ffffffff1ff7a18 R12: ffff888025c928f8
R13: 0000000000000002 R14: 0000000000000015 R15: ffff888025c928f8
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33a63fff CR3: 0000000074784000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 __perf_output_begin kernel/events/ring_buffer.c:163 [inline]
 perf_output_begin_forward+0x97/0xa30 kernel/events/ring_buffer.c:271
 __perf_event_output kernel/events/core.c:7804 [inline]
 perf_event_output_forward+0x15c/0x280 kernel/events/core.c:7822
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_swevent_overflow kernel/events/core.c:9591 [inline]
 perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629
 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 ad 13 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: 0018:ffffc9000cc17420 EFLAGS: 00000206
RAX: 0d7e13e3f8ad8e00 RBX: 1ffff92001982e88 RCX: 0d7e13e3f8ad8e00
RDX: dffffc0000000000 RSI: ffffffff8a0b1820 RDI: ffffffff8a59a4c0
RBP: ffffc9000cc174f0 R08: dffffc0000000000 R09: fffffbfff1ff7a19
R10: fffffbfff1ff7a19 R11: 1ffffffff1ff7a18 R12: ffffffff8c120b00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:771 [inline]
 __unlock_page_memcg+0xea/0x100 mm/memcontrol.c:2093
 zap_pte_range mm/memory.c:1384 [inline]
 zap_pmd_range mm/memory.c:1505 [inline]
 zap_pud_range mm/memory.c:1534 [inline]
 zap_p4d_range mm/memory.c:1555 [inline]
 unmap_page_range+0xfbc/0x2520 mm/memory.c:1576
 unmap_vmas+0x11b/0x230 mm/memory.c:1653
 exit_mmap+0x38f/0x5f0 mm/mmap.c:3216
 __mmput+0x115/0x3b0 kernel/fork.c:1127
 exit_mm+0x567/0x6c0 kernel/exit.c:550
 do_exit+0x5a1/0x20a0 kernel/exit.c:870
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 get_signal+0x6ca/0x12c0 kernel/signal.c:2900
 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa915e4dec9
Code: Unable to access opcode bytes at RIP 0x7fa915e4de9f.
RSP: 002b:00007fa9154bd0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fa9160a4fa8 RCX: 00007fa915e4dec9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fa9160a4fa8
RBP: 00007fa9160a4fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa9160a5038 R14: 00007fffec2879e0 R15: 00007fffec287ac8
 </TASK>