rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (0 ticks this GP) idle=339c/1/0x4000000000000000 softirq=161753/161753 fqs=2 rcu: (detected by 1, t=10502 jiffies, g=150241, q=388 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 29888 Comm: syz.1.8907 Not tainted 6.16.0-syzkaller-11895-gcca7a0aae895 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x98/0x110 kernel/locking/spinlock.c:194 Code: 22 f6 4c 89 f7 e8 c8 d4 22 f6 f7 c3 00 02 00 00 74 05 e8 ab 26 4c f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 <75> 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 e8 f3 cd 14 f6 65 RSP: 0018:ffffc90000007ca0 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000016 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b8627a80 RBP: ffffc90000007d30 R08: ffff8880b8627a83 R09: 1ffff110170c4f50 R10: dffffc0000000000 R11: ffffed10170c4f51 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff8880b8627a80 R15: 1ffff92000000f94 FS: 0000000000000000(0000) GS:ffff888125c24000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c40a77c CR3: 000000005e5f3000 CR4: 0000000000350ef0 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1757 [inline] __hrtimer_run_queues+0x408/0xc60 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:xa_is_value include/linux/xarray.h:85 [inline] RIP: 0010:shmem_undo_range+0x2da/0x14b0 mm/shmem.c:1144 Code: 81 bf ff 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 f7 e8 3e ec 22 00 4e 8b ac fc c0 00 00 00 <4c> 89 ee 48 83 e6 01 31 ff e8 68 86 bf ff 4c 89 e8 48 83 e0 01 0f RSP: 0018:ffffc90003a2f500 EFLAGS: 00000246 RAX: 1ffff92000745ec1 RBX: 0000000000000008 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 000000000000001f RBP: ffffc90003a2f8b0 R08: ffffea0001414c07 R09: 1ffffd4000282980 R10: dffffc0000000000 R11: fffff94000282981 R12: ffffc90003a2f740 R13: ffffea000045bac0 R14: ffffc90003a2f608 R15: 0000000000000009 shmem_truncate_range mm/shmem.c:1269 [inline] shmem_evict_inode+0x272/0xa70 mm/shmem.c:1397 evict+0x504/0x9c0 fs/inode.c:810 __dentry_kill+0x209/0x660 fs/dcache.c:669 dput+0x19f/0x2b0 fs/dcache.c:911 __fput+0x68e/0xa70 fs/file_table.c:476 task_work_run+0x1d4/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x2300 kernel/exit.c:961 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 __do_sys_exit_group kernel/exit.c:1113 [inline] __se_sys_exit_group kernel/exit.c:1111 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0b17f8ebe9 Code: Unable to access opcode bytes at 0x7f0b17f8ebbf. RSP: 002b:00007ffc18cc9928 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0b17f8ebe9 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffc18cc998c R08: 0000000418cc9a1f R09: 00000000000927c0 R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000006b6 R13: 00000000000927c0 R14: 000000000010359a R15: 00007ffc18cc99e0 rcu: rcu_preempt kthread starved for 10490 jiffies! g150241 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:27400 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 29895 Comm: syz.7.8909 Not tainted 6.16.0-syzkaller-11895-gcca7a0aae895 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xd38/0x12d0 kernel/smp.c:877 Code: 89 ee 83 e6 01 31 ff e8 b6 62 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5e 0b 00 eb 38 f3 90 42 0f b6 04 2b <84> c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 45 5e 0b 00 eb e4 44 RSP: 0018:ffffc9000389f560 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff110170c8341 RCX: 0000000000080000 RDX: ffffc9000b879000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc9000389f6e0 R08: ffffffff8fa34237 R09: 1ffffffff1f46846 R10: dffffc0000000000 R11: fffffbfff1f46847 R12: ffff8880b8641a08 R13: dffffc0000000000 R14: ffff8880b873b1c0 R15: 0000000000000000 FS: 00007f5e7eff66c0(0000) GS:ffff888125d24000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055558cdc0808 CR3: 000000005a270000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline] flush_tlb_mm_range+0x6b1/0x12d0 arch/x86/mm/tlb.c:1451 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline] tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497 vms_clear_ptes+0x42c/0x540 mm/vma.c:1235 vms_complete_munmap_vmas+0x206/0x8a0 mm/vma.c:1277 do_vmi_align_munmap+0x358/0x420 mm/vma.c:1536 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1584 __vm_munmap+0x23b/0x3d0 mm/vma.c:3155 __do_sys_munmap mm/mmap.c:1080 [inline] __se_sys_munmap mm/mmap.c:1077 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1077 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5e80d8ec77 Code: 00 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 0b 00 00 00 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:00007f5e7eff5e18 EFLAGS: 00000246 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 00000000013bd7ef RCX: 00007f5e80d8ec77 RDX: 0000000000000000 RSI: 0000000008400000 RDI: 00007f5e76a00000 RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000550b R10: 00002000000079c2 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f5e7eff5ef0 R14: 00007f5e7eff5eb0 R15: 00007f5e76a00000