rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=0a34/1/0x4000000000000000 softirq=22336/22337 fqs=108 rcu: (detected by 0, t=10502 jiffies, g=19513, q=188 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 7104 Comm: syz-executor Not tainted 6.14.0-rc3-syzkaller-00295-g27102b38b8ca #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:mark_lock+0x15/0x360 kernel/locking/lockdep.c:4712 Code: 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 48 83 ec 10 49 89 f7 48 89 3c 24 <49> bd 00 00 00 00 00 fc ff df 83 fa 08 75 27 49 8d 5f 20 48 89 d8 RSP: 0018:ffffc90000a188e8 EFLAGS: 00000086 RAX: 0000000000000001 RBX: 1ffff11005f908ec RCX: 00000000000c4000 RDX: 0000000000000000 RSI: ffff88802fc84740 RDI: ffff88802fc83c00 RBP: ffff88802fc84740 R08: ffffffff9451184f R09: 1ffffffff28a2309 R10: dffffc0000000000 R11: fffffbfff28a230a R12: ffff88802fc846d4 R13: ffff88802fc83c00 R14: 0000000000000000 R15: ffff88802fc84740 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3f6cb1 CR3: 0000000056016000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_usage kernel/locking/lockdep.c:4637 [inline] __lock_acquire+0xbc3/0x2100 kernel/locking/lockdep.c:5182 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __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:460 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:502 __run_hrtimer kernel/time/hrtimer.c:1769 [inline] __hrtimer_run_queues+0x305/0xd30 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 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:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210 Code: 89 fb e8 23 00 00 00 48 8b 3d c4 05 92 0c 48 89 de 5b e9 23 5e 59 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 00 d5 03 00 65 8b 15 50 17 RSP: 0018:ffffc90005a07a78 EFLAGS: 00000246 RAX: ffffffff8215211e RBX: 00000000ff000000 RCX: ffff88802fc83c00 RDX: 0000000000000000 RSI: 00000000ff000000 RDI: 00000000f5000000 RBP: ffffc90005a07b50 R08: ffffffff82152104 R09: 1ffffffff28a2308 R10: dffffc0000000000 R11: fffffbfff28a2309 R12: ffffea0001d8af80 R13: 0000000000000000 R14: ffffea0001d8afb0 R15: 0000000000000000 mod_memcg_page_state+0x476/0x800 include/linux/memcontrol.h:934 vfree+0x1af/0x360 mm/vmalloc.c:3378 kcov_put kernel/kcov.c:439 [inline] kcov_close+0x28/0x50 kernel/kcov.c:535 __fput+0x3e9/0x9f0 fs/file_table.c:464 task_work_run+0x24f/0x310 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2a/0x28e0 kernel/exit.c:938 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 __do_sys_exit_group kernel/exit.c:1098 [inline] __se_sys_exit_group kernel/exit.c:1096 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096 x64_sys_call+0x26a8/0x26b0 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: 0033:0x7f1543f8d169 Code: Unable to access opcode bytes at 0x7f1543f8d13f. RSP: 002b:00007fff82eb4ef8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000043 RCX: 00007f1543f8d169 RDX: 00007f1543f8bbe0 RSI: 0000000000000004 RDI: 0000000000000043 RBP: 00007f15441a6738 R08: 00007fff82eb2c96 R09: 0000000000000008 R10: 000000000000001a R11: 0000000000000246 R12: 0000000000000008 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10286 jiffies! g19513 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:25240 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x18bc/0x4c40 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 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: 6342 Comm: udevd Not tainted 6.14.0-rc3-syzkaller-00295-g27102b38b8ca #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1ba4/0x2d30 kernel/smp.c:885 Code: 03 84 c0 75 7e 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 30 f5 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 e0 f0 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00 RSP: 0018:ffffc9000ec174e0 EFLAGS: 00000293 RAX: ffffffff81b5cce5 RBX: 1ffff110170e88c9 RCX: ffff888025b09e00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000ec176e0 R08: ffffffff81b5ccb0 R09: 1ffffffff28a230e R10: dffffc0000000000 R11: fffffbfff28a230f R12: ffff8880b863f9c8 R13: ffff8880b8744648 R14: ffff8880b863f9c0 R15: 0000000000000001 FS: 00007f5bdd4a8c80(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c34f288 CR3: 000000003487e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:966 [inline] flush_tlb_mm_range+0x42d/0x710 arch/x86/mm/tlb.c:1054 tlb_flush arch/x86/include/asm/tlb.h:20 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:481 [inline] tlb_flush_mmu+0x1aa/0x680 mm/mmu_gather.c:395 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:488 vms_clear_ptes+0x432/0x530 mm/vma.c:1144 vms_complete_munmap_vmas+0x210/0x8f0 mm/vma.c:1186 do_vmi_align_munmap+0x5ef/0x6f0 mm/vma.c:1445 do_vmi_munmap+0x24e/0x2d0 mm/vma.c:1493 __vm_munmap+0x372/0x510 mm/vma.c:2951 __do_sys_munmap mm/mmap.c:1084 [inline] __se_sys_munmap mm/mmap.c:1081 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1081 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: 0033:0x7f5bdd585817 Code: ff ff 76 10 48 8b 15 10 36 0d 00 f7 d8 64 89 02 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 35 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007ffdd772e8e8 EFLAGS: 00000206 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 000055bce986d5b0 RCX: 00007f5bdd585817 RDX: 000055b859b27959 RSI: 0000000000906623 RDI: 00007f5bdc800000 RBP: 000055bd0261dc20 R08: 0000000000000003 R09: 463025999bbf93f7 R10: 00000000ffffffff R11: 0000000000000206 R12: 000055bce986d5e8 R13: 00007ffdd772e968 R14: 0000000000000001 R15: 000055bd0260d910