syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=3fec/1/0x4000000000000000 softirq=93533/93533 fqs=4
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5265/1:b..l P942/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=141933, q=124 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5267 Comm: syz-executor.5 Not tainted 6.7.0-rc5-syzkaller-00014-g26aff849438c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xd/0x60 kernel/kcov.c:207
Code: fa 48 8b be b0 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 65 48 8b 14 25 c0 bc 03 00 <65> 8b 05 b4 2e 7c 7e a9 00 01 ff 00 48 8b 34 24 74 0f f6 c4 01 74
RSP: 0018:ffffc900001f0dd0 EFLAGS: 00000046
RAX: 0000000000010001 RBX: ffff888079665340 RCX: ffffffff8a71fae8
RDX: ffff88801ffe9dc0 RSI: ffff888079665340 RDI: 0000000000000006
RBP: ffff888079665340 R08: 0000000000000006 R09: ffff888079665340
R10: ffff888079665340 R11: 0000000000000001 R12: ffff8880b992b940
R13: 0000000000000002 R14: ffff888079665340 R15: 0000000000000001
FS:  0000555555f4e480(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdbbc998000 CR3: 0000000015b3e000 CR4: 0000000000350ef0
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 timerqueue_add+0x56/0x330 lib/timerqueue.c:40
 enqueue_hrtimer+0x16f/0x310 kernel/time/hrtimer.c:1094
 __run_hrtimer kernel/time/hrtimer.c:1705 [inline]
 __hrtimer_run_queues+0xa12/0xc20 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline]
 __sysvec_apic_timer_interrupt+0x105/0x400 arch/x86/kernel/apic/apic.c:1082
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1076
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:__syscall_enter_from_user_work kernel/entry/common.c:91 [inline]
RIP: 0010:syscall_enter_from_user_mode+0x89/0x120 kernel/entry/common.c:112
Code: 85 b1 00 00 00 48 8b 7c 24 18 e8 a2 f9 ff ff 66 90 66 90 90 e8 68 26 0e f7 90 90 e8 d1 24 0e f7 fb 65 48 8b 04 25 c0 bc 03 00 <48> 8b 70 08 40 f6 c6 3f 75 6c 90 5b 48 89 e8 5d 41 5c c3 b8 00 44
RSP: 0018:ffffc9000aa17f20 EFLAGS: 00000202
RAX: ffff88801ffe9dc0 RBX: ffffc9000aa17f58 RCX: 1ffffffff1e32221
RDX: 0000000000000000 RSI: ffffffff8accb520 RDI: ffffffff8b2f0e20
RBP: 0000000000000003 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff8f194397 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 do_syscall_64+0x1c/0x110 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fdbbc87ba9a
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24
RSP: 002b:00007ffeec64cf00 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fdbbc87ba9a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 0000000000000032 R08: 0000001b32720000 R09: 000000000000011f
R10: 0000000081730447 R11: 0000000000000293 R12: 00007fdbbc400098
R13: ffffffffffffffff R14: 00007fdbbc400000 R15: 00000000002ae9cc
 </TASK>
task:kworker/u4:2    state:R  running task     stack:26960 pid:942   tgid:942   ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5376 [inline]
 __schedule+0xedb/0x5af0 kernel/sched/core.c:6688
 preempt_schedule_irq+0x52/0x90 kernel/sched/core.c:7008
 irqentry_exit+0x36/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:get_current arch/x86/include/asm/current.h:41 [inline]
RIP: 0010:__rcu_read_lock+0x8f/0xf0 kernel/rcu/tree_plugin.h:404
Code: ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c3 01 83 c0 03 38 d0 7c 04 84 d2 75 5a 48 b8 00 00 00 00 00 fc ff df 89 9d 3c 04 00 00 <65> 48 8b 1c 25 c0 bc 03 00 48 8d bb 3c 04 00 00 48 89 fa 48 c1 ea
RSP: 0018:ffffc90009d27ae0 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8accb820 RDI: ffff88802564843c
RBP: ffff888025648000 R08: 0000000000000004 R09: 000000000007ffff
R10: 000000000003597f R11: 0000000000000003 R12: 0000000000000000
R13: 000000000003597f R14: dffffc0000000000 R15: 000000000003597e
 rcu_read_lock include/linux/rcupdate.h:745 [inline]
 inet_twsk_purge+0x10c/0x900 net/ipv4/inet_timewait_sock.c:292
 ops_exit_list+0x125/0x170 net/core/net_namespace.c:175
 cleanup_net+0x505/0xb20 net/core/net_namespace.c:614
 process_one_work+0x886/0x15d0 kernel/workqueue.c:2627
 process_scheduled_works kernel/workqueue.c:2700 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2781
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
task:dhcpcd          state:R  running task     stack:28704 pid:5265  tgid:5265  ppid:4737   flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5376 [inline]
 __schedule+0xedb/0x5af0 kernel/sched/core.c:6688
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6865
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3a/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 wp_page_copy mm/memory.c:3228 [inline]
 do_wp_page+0x1a65/0x36b0 mm/memory.c:3511
 handle_pte_fault mm/memory.c:5055 [inline]
 __handle_mm_fault+0x1d7d/0x3d70 mm/memory.c:5180
 handle_mm_fault+0x47a/0xa10 mm/memory.c:5345
 do_user_addr_fault+0x30b/0x1000 arch/x86/mm/fault.c:1364
 handle_page_fault arch/x86/mm/fault.c:1505 [inline]
 exc_page_fault+0x5d/0xc0 arch/x86/mm/fault.c:1561
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7f8a04c87cfe
RSP: 002b:00007ffc5f42af20 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00007f8a04c9f1a0 RCX: 00007f8a04e71150
RDX: 000055c9a5cd3810 RSI: 00007f8a04e820c9 RDI: 0000000000000000
RBP: 000055c9a5cd3810 R08: 00007ffc5f42af90 R09: 00007ffc5f42b070
R10: 00007ffc5f42afd0 R11: 0000000000000007 R12: 00007f8a04c9d4f8
R13: 00007f8a04eaea80 R14: 0000000000000003 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10494 jiffies! g141933 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:27904 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5376 [inline]
 __schedule+0xedb/0x5af0 kernel/sched/core.c:6688
 __schedule_loop kernel/sched/core.c:6763 [inline]
 schedule+0xe9/0x270 kernel/sched/core.c:6778
 schedule_timeout+0x137/0x290 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x1ec/0xb10 kernel/rcu/tree.c:1631
 rcu_gp_kthread+0x24b/0x380 kernel/rcu/tree.c:1830
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 4606 Comm: kworker/u4:7 Not tainted 6.7.0-rc5-syzkaller-00014-g26aff849438c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0x4e9/0x1550 kernel/smp.c:855
Code: 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 9e b8 0b 00 f3 90 41 0f b6 04 24 <40> 38 c5 7c 08 84 c0 0f 85 24 0e 00 00 8b 43 08 31 ff 83 e0 01 41
RSP: 0018:ffffc9000450f930 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b9941a60 RCX: ffffffff817bd588
RDX: ffff888025a5d940 RSI: ffffffff817bd562 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000006 R12: ffffed101732834d
R13: 0000000000000001 R14: ffff8880b9941a68 R15: ffff8880b983d8c0
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffee46c4d68 CR3: 000000000cd77000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1023
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2006 [inline]
 text_poke_bp_batch+0x22b/0x750 arch/x86/kernel/alternative.c:2216
 text_poke_flush arch/x86/kernel/alternative.c:2407 [inline]
 text_poke_flush arch/x86/kernel/alternative.c:2404 [inline]
 text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2414
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 jump_label_update+0x1d7/0x400 kernel/jump_label.c:829
 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:205
 static_key_enable+0x1a/0x20 kernel/jump_label.c:218
 toggle_allocation_gate mm/kfence/core.c:830 [inline]
 toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:822
 process_one_work+0x886/0x15d0 kernel/workqueue.c:2627
 process_scheduled_works kernel/workqueue.c:2700 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2781
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>