rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=173c/1/0x4000000000000000 softirq=24803/24804 fqs=1 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8200/1:b..l rcu: (detected by 0, t=10505 jiffies, g=32873, q=257 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 8225 Comm: syz.1.803 Not tainted 6.11.0-rc2-syzkaller-00013-gd4560686726f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:__lock_release kernel/locking/lockdep.c:5413 [inline] RIP: 0010:lock_release+0x1c3/0xa30 kernel/locking/lockdep.c:5780 Code: 80 3c 3b 00 74 08 4c 89 f7 e8 c9 cc 8a 00 48 8b 9c 24 b0 00 00 00 fa 48 c7 c7 40 e2 0a 8c e8 34 05 46 0a 65 ff 05 ad a6 92 7e <48> 8d 94 24 80 00 00 00 48 c1 ea 03 42 0f b6 04 3a 84 c0 0f 85 6e RSP: 0018:ffffc90000a18b40 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000046 RCX: ffffffff816fe2c0 RDX: 0000000000000000 RSI: ffffffff8c0ae240 RDI: ffffffff8c605d00 RBP: ffffc90000a18c70 R08: ffffffff9017c16f R09: 1ffffffff202f82d R10: dffffc0000000000 R11: fffffbfff202f82e R12: 1ffff92000143174 R13: ffffffff89bcc274 R14: ffffc90000a18bf0 R15: dffffc0000000000 FS: 00007f117c79d6c0(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020028000 CR3: 00000000610e2000 CR4: 0000000000350ef0 Call Trace: __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline] _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] advance_sched+0x9b4/0xca0 net/sched/sch_taprio.c:981 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x59d/0xd50 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1815 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x112/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__might_sleep+0x5/0xe0 kernel/sched/core.c:8379 Code: 61 8a 85 03 e9 5f fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <41> 57 41 56 41 55 41 54 53 41 89 f6 49 89 ff 49 bc 00 00 00 00 00 RSP: 0018:ffffc90009217b78 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffff888062a78000 RCX: 0000000000040000 RDX: ffff888062a78000 RSI: 00000000000000b0 RDI: ffffffff8c600cc0 RBP: 0000000000000000 R08: ffffffff81e1d371 R09: 1ffffffff202f82d R10: dffffc0000000000 R11: fffffbfff202f82e R12: dffffc0000000000 R13: 0000000000018ff0 R14: 00000000000000b0 R15: ffffffff8c600cc0 __might_fault+0x72/0x120 mm/memory.c:6385 _inline_copy_to_user include/linux/uaccess.h:176 [inline] _copy_to_user+0x2a/0xb0 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:209 [inline] msr_read+0x187/0x260 arch/x86/kernel/msr.c:69 vfs_read+0x206/0xbc0 fs/read_write.c:474 ksys_read+0x1a0/0x2c0 fs/read_write.c:619 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: 0033:0x7f117b9779f9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f117c79d048 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f117bb05f80 RCX: 00007f117b9779f9 RDX: 0000000000018ff8 RSI: 0000000020019680 RDI: 0000000000000003 RBP: 00007f117b9e58ee R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f117bb05f80 R15: 00007ffc50b83238 task:syz.0.794 state:R running task stack:24672 pid:8200 tgid:8200 ppid:7294 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6708 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6732 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] zap_pte_range mm/memory.c:1688 [inline] zap_pmd_range mm/memory.c:1736 [inline] zap_pud_range mm/memory.c:1765 [inline] zap_p4d_range mm/memory.c:1786 [inline] unmap_page_range+0x3818/0x42c0 mm/memory.c:1807 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1897 exit_mmap+0x264/0xc80 mm/mmap.c:3412 __mmput+0x115/0x390 kernel/fork.c:1345 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x27f0 kernel/exit.c:869 do_group_exit+0x207/0x2c0 kernel/exit.c:1031 __do_sys_exit_group kernel/exit.c:1042 [inline] __se_sys_exit_group kernel/exit.c:1040 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232 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: 0033:0x7f1d781779f9 RSP: 002b:00007ffe9cdb7738 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1d781779f9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffe9cdb778c R08: 0000000000000006 R09: 00000000000500c4 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000032 R13: 00000000000500c4 R14: 000000000004fd2b R15: 00007ffe9cdb77e0 rcu: rcu_preempt kthread starved for 10500 jiffies! g32873 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:26448 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 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: 0 UID: 0 PID: 53 Comm: kworker/u8:3 Not tainted 6.11.0-rc2-syzkaller-00013-gd4560686726f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline] RIP: 0010:cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline] RIP: 0010:csd_lock_wait kernel/smp.c:312 [inline] RIP: 0010:smp_call_function_many_cond+0x185e/0x29d0 kernel/smp.c:856 Code: 00 00 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 99 14 0c 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 44 10 0c 00 eb 38 90 42 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 RSP: 0018:ffffc90000bd7700 EFLAGS: 00000293 RAX: ffffffff818766c8 RBX: 1ffff110172688f9 RCX: ffff8880159bda00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000bd78e0 R08: ffffffff81876697 R09: 1ffffffff26e5900 R10: dffffc0000000000 R11: fffffbfff26e5901 R12: dffffc0000000000 R13: ffff8880b93447c8 R14: ffff8880b923fb80 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f59ddb05f84 CR3: 000000000e734000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023 text_poke_bp_batch+0x9ef/0xb30 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+0xb5/0x250 mm/kfence/core.c:833 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 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