rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=cc5/1/0x4000000000000002 softirq=10355/10355 fqs=0 
	(detected by 1, t=10506 jiffies, g=13277, q=966)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3854 Comm: dhcpcd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:172 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:227 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0xc/0x80 kernel/kcov.c:293
Code: 44 02 08 03 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 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
RSP: 0018:ffffc900010def58 EFLAGS: 00000046
RAX: ffffffff819a0b98 RBX: ffff88805ce291e8 RCX: ffff888029d79dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900010df090 R08: dffffc0000000000 R09: fffffbfff1ff5419
R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: 1ffff9200021bdfc
R13: 0000000000000008 R14: 0000000000000001 R15: ffffc900010df300
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc7c4599f98 CR3: 000000002307f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 rcu_read_lock include/linux/rcupdate.h:741 [inline]
 __perf_output_begin kernel/events/ring_buffer.c:163 [inline]
 perf_output_begin_forward+0xa8/0xa30 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 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: 0018:ffffc900010df760 EFLAGS: 00000206
RAX: 476d7992a88cca00 RBX: 1ffff9200021bef0 RCX: 476d7992a88cca00
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800
RBP: ffffc900010df830 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
 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
 __do_sys_exit_group kernel/exit.c:1008 [inline]
 __se_sys_exit_group kernel/exit.c:1006 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2202f436c5
Code: Unable to access opcode bytes at RIP 0x7f2202f4369b.
RSP: 002b:00007ffc2c913268 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f2202f436c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000
RBP: 00007ffc2c913878 R08: 0000556b40cc12c0 R09: 0000000000000002
R10: 0000000000000020 R11: 0000000000000206 R12: 00007ffc2c9132b0
R13: 0000556b40cc28f0 R14: 00007ffc2c9134f0 R15: 00007ffc2c9132a0
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g13277 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=8648
rcu: rcu_preempt kthread starved for 10506 jiffies! g13277 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:27968 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: 3854 Comm: dhcpcd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x0/0x80 kernel/kcov.c:301
Code: 28 4d 39 ca 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 c4 9f 8a 7e 65 8b 15 c5 9f 8a 7e 81 e2 00
RSP: 0018:ffffc900010def98 EFLAGS: 00000046
RAX: ffffffff8196511d RBX: ffffc900010df140 RCX: ffff888029d79dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900010df090 R08: dffffc0000000000 R09: ffffc900010df0e0
R10: fffff5200021be23 R11: 1ffff9200021be1c R12: dffffc0000000000
R13: ffffc900010df146 R14: 0000000000000000 R15: ffffc900010df300
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc7c4599f98 CR3: 000000002307f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 perf_prepare_sample+0x97b/0x1cb0 kernel/events/core.c:7692
 __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 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: 0018:ffffc900010df760 EFLAGS: 00000206
RAX: 476d7992a88cca00 RBX: 1ffff9200021bef0 RCX: 476d7992a88cca00
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800
RBP: ffffc900010df830 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
 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
 __do_sys_exit_group kernel/exit.c:1008 [inline]
 __se_sys_exit_group kernel/exit.c:1006 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2202f436c5
Code: Unable to access opcode bytes at RIP 0x7f2202f4369b.
RSP: 002b:00007ffc2c913268 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f2202f436c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000
RBP: 00007ffc2c913878 R08: 0000556b40cc12c0 R09: 0000000000000002
R10: 0000000000000020 R11: 0000000000000206 R12: 00007ffc2c9132b0
R13: 0000556b40cc28f0 R14: 00007ffc2c9134f0 R15: 00007ffc2c9132a0
 </TASK>