rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=d1ec/1/0x4000000000000000 softirq=16995/16999 fqs=1 rcu: (detected by 1, t=10505 jiffies, g=11493, q=777 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5844 Comm: syz-executor Not tainted 6.12.0-syzkaller-10689-g7af08b57bcb9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:__lock_acquire+0x12be/0x2100 kernel/locking/lockdep.c:5223 Code: 10 8b 18 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 80 18 32 94 be 08 00 00 00 e8 2a 98 8f 00 48 0f a3 1d 92 e4 c0 12 <73> 1d 48 69 c3 c8 00 00 00 48 8d 98 40 97 c9 93 48 ba 00 00 00 00 RSP: 0018:ffffc90000007930 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff817133e6 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff94321880 RBP: 97064f26aa3bd169 R08: ffffffff94321887 R09: 1ffffffff2864310 R10: dffffc0000000000 R11: fffffbfff2864311 R12: ffff88802e931e00 R13: ffff88802e931e00 R14: 1ffff11005d26548 R15: 0000000000000000 FS: 000055555fb7a500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6543a756c0 CR3: 000000005c3b2000 CR4: 0000000000350ef0 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 debug_object_deactivate+0x158/0x390 lib/debugobjects.c:873 debug_hrtimer_deactivate kernel/time/hrtimer.c:433 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:475 __run_hrtimer kernel/time/hrtimer.c:1707 [inline] __hrtimer_run_queues+0x305/0xd30 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216 Code: 8b 3d 84 f0 9d 0c 48 89 de 5b e9 d3 cd 5e 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 d4 03 00 65 8b 15 e0 f2 6d 7e 81 e2 00 01 ff 00 RSP: 0018:ffffc900045ef2a0 EFLAGS: 00000246 RAX: ffffffff81e73cdf RBX: ffffea0001a84cc0 RCX: ffff88802e931e00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffea0001a84cc8 R08: ffffffff81e73cb7 R09: 1ffffd400035099e R10: dffffc0000000000 R11: fffff9400035099f R12: ffffea0001a84cc0 R13: dffffc0000000000 R14: ffffea0001a84cc0 R15: 0000000000000001 __folio_rmap_sanity_checks+0xff/0x3a0 include/linux/rmap.h:216 copy_pte_range mm/memory.c:1173 [inline] copy_pmd_range+0xc23/0x7eb0 mm/memory.c:1261 copy_pud_range mm/memory.c:1298 [inline] copy_p4d_range mm/memory.c:1322 [inline] copy_page_range+0x99f/0xe90 mm/memory.c:1420 dup_mmap kernel/fork.c:751 [inline] dup_mm kernel/fork.c:1695 [inline] copy_mm+0x11c7/0x1f90 kernel/fork.c:1744 copy_process+0x1845/0x3d50 kernel/fork.c:2395 kernel_clone+0x226/0x8e0 kernel/fork.c:2807 __do_sys_clone kernel/fork.c:2950 [inline] __se_sys_clone kernel/fork.c:2934 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2934 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6542d77053 Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffca0864d38 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6542d77053 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 000055555fb7a7d0 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000002a526 R14: 000000000002a38e R15: 00007ffca0864ec0 rcu: rcu_preempt kthread starved for 10490 jiffies! g11493 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 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:24152 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 51 Comm: kworker/u8:3 Not tainted 6.12.0-syzkaller-10689-g7af08b57bcb9 #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+0x19f8/0x2c60 kernel/smp.c:884 Code: 89 e6 83 e6 01 31 ff e8 66 e9 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 11 e5 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 f5 e4 0b 00 eb e4 44 RSP: 0018:ffffc90000bb76e0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff110170c8c61 RCX: ffff8880226e1e00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000bb78e0 R08: ffffffff8189fcaa R09: 1ffffffff2864310 R10: dffffc0000000000 R11: fffffbfff2864311 R12: dffffc0000000000 R13: ffff8880b8646308 R14: ffff8880b873f980 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007efcb28756c0 CR3: 000000000e738000 CR4: 0000000000350ef0 Call Trace: 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:2114 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2522 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+0xa68/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244