syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=a0c4/1/0x4000000000000000 softirq=36089/36089 fqs=6
rcu: 	(detected by 0, t=10502 jiffies, g=30257, q=1010 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7194 Comm: syz-executor Not tainted 6.12.0-rc3-syzkaller-00013-geca631b8fe80 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210
Code: 89 fb e8 23 00 00 00 48 8b 3d 04 fb 9c 0c 48 89 de 5b e9 c3 c7 5d 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 c0 d7 03 00 65 8b 15 60 f0
RSP: 0018:ffffc90000a18d58 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffff8880b872c948 RCX: ffffffff818244b0
RDX: ffff88802d585a00 RSI: ffffffff8c60fc80 RDI: ffffffff8c60fc40
RBP: ffffc90000a18ea8 R08: ffffffff818244d6 R09: 1ffffffff2039edd
R10: dffffc0000000000 R11: fffffbfff2039ede R12: 1ffff110170e592b
R13: 0000000000000001 R14: ffff88805ef15340 R15: ffff8880b872c880
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f75ccc9c CR3: 00000000322ee000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 trace_hrtimer_expire_exit include/trace/events/timer.h:306 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1694 [inline]
 __hrtimer_run_queues+0x643/0xd50 kernel/time/hrtimer.c:1755
 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline]
 __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1043
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1037
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5829
Code: 2b 00 74 08 4c 89 f7 e8 8a 3f 8e 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc9000daf7380 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92001b5ee7c RCX: a50c2cd9a2d3dd00
RDX: dffffc0000000000 RSI: ffffffff8c0adc40 RDI: ffffffff8c60fca0
RBP: ffffc9000daf74d0 R08: ffffffff942c8807 R09: 1ffffffff2859100
R10: dffffc0000000000 R11: fffffbfff2859101 R12: 1ffff92001b5ee78
R13: dffffc0000000000 R14: ffffc9000daf73e0 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 rcu_read_lock_sched include/linux/rcupdate.h:941 [inline]
 pfn_valid+0x113/0x450 include/linux/mmzone.h:2043
 page_table_check_clear+0x1e/0x550 mm/page_table_check.c:70
 get_and_clear_full_ptes include/linux/pgtable.h:684 [inline]
 zap_present_folio_ptes mm/memory.c:1496 [inline]
 zap_present_ptes mm/memory.c:1579 [inline]
 zap_pte_range mm/memory.c:1621 [inline]
 zap_pmd_range mm/memory.c:1739 [inline]
 zap_pud_range mm/memory.c:1768 [inline]
 zap_p4d_range mm/memory.c:1789 [inline]
 unmap_page_range+0x2a13/0x40e0 mm/memory.c:1810
 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900
 exit_mmap+0x275/0xc40 mm/mmap.c:1864
 __mmput+0x115/0x390 kernel/fork.c:1347
 exit_mm+0x220/0x310 kernel/exit.c:571
 do_exit+0x9b2/0x28e0 kernel/exit.c:926
 do_group_exit+0x207/0x2c0 kernel/exit.c:1088
 __do_sys_exit_group kernel/exit.c:1099 [inline]
 __se_sys_exit_group kernel/exit.c:1097 [inline]
 __ia32_sys_exit_group+0x3f/0x40 kernel/exit.c:1097
 ia32_sys_call+0x2624/0x2630 arch/x86/include/generated/asm/syscalls_32.h:253
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7fe6579
Code: Unable to access opcode bytes at 0xf7fe654f.
RSP: 002b:00000000f75cec9c EFLAGS: 00000206 ORIG_RAX: 00000000000000fc
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00000000f75ceda0
RDX: 00000000f727fdd7 RSI: 0000000000000000 RDI: 00000000f7340a37
RBP: 00000000f75cecf8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10490 jiffies! g30257 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:25952 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5322 [inline]
 __schedule+0x1895/0x4b30 kernel/sched/core.c:6682
 __schedule_loop kernel/sched/core.c:6759 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6774
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 1074 Comm: kworker/u8:6 Not tainted 6.12.0-rc3-syzkaller-00013-geca631b8fe80 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x19f3/0x2ca0 kernel/smp.c:884
Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 56 f3 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 01 ef 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 e5 ee
RSP: 0018:ffffc90003f576e0 EFLAGS: 00000293
RAX: ffffffff8188f86b RBX: 1ffff110170e8919 RCX: ffff8880273f1e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003f578e0 R08: ffffffff8188f83a R09: 1ffffffff2859100
R10: dffffc0000000000 R11: fffffbfff2859101 R12: dffffc0000000000
R13: ffff8880b87448c8 R14: ffff8880b863fc80 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f281b777108 CR3: 000000000e734000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2085 [inline]
 text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2295
 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline]
 text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2493
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate+0xbc/0x260 mm/kfence/core.c:849
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>