rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=bdcc/1/0x4000000000000000 softirq=107045/107045 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P18843/1:b..l rcu: (detected by 0, t=10502 jiffies, g=74061, q=267 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 18888 Comm: syz.7.4450 Not tainted 6.16.0-rc1-syzkaller-00203-g4774cfe3543a #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_preemption_disabled+0x1e/0x120 lib/smp_processor_id.c:16 Code: 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 7e 7e 36 07 48 89 44 24 08 65 8b 05 86 7e 36 07 <65> 8b 0d 7b 7e 36 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d 5b 7e 36 RSP: 0018:ffffc90000a08bc0 EFLAGS: 00000086 RAX: 0000000000000001 RBX: 0000000000000002 RCX: dc3c95bc37d72800 RDX: 0000000000010000 RSI: ffffffff8d99545d RDI: ffffffff8be28700 RBP: ffff88805a51a150 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200014117c R12: ffff88807b1f0340 R13: ffffffff8985f7ef R14: ffff88807b1f0300 R15: ffff88802f5e3c00 FS: 0000000000000000(0000) GS:ffff888125d52000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000040 CR3: 000000000df38000 CR4: 0000000000350ef0 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:468 [inline] lock_release+0xbc/0x3e0 kernel/locking/lockdep.c:5891 __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+0x99f/0xc90 net/sched/sch_taprio.c:981 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x52c/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:zap_present_ptes arch/x86/include/asm/jump_label.h:-1 [inline] RIP: 0010:do_zap_pte_range mm/memory.c:1691 [inline] RIP: 0010:zap_pte_range mm/memory.c:1735 [inline] RIP: 0010:zap_pmd_range mm/memory.c:1827 [inline] RIP: 0010:zap_pud_range mm/memory.c:1856 [inline] RIP: 0010:zap_p4d_range mm/memory.c:1877 [inline] RIP: 0010:unmap_page_range+0xee8/0x41c0 mm/memory.c:1898 Code: ff e8 8c 4a b6 ff 4c 89 e0 48 83 e0 01 4c 8b 6c 24 10 0f 85 7a 14 00 00 0f 1f 44 00 00 e8 90 45 b6 ff 4c 8b a4 24 80 00 00 00 <48> 83 bc 24 d0 00 00 00 00 48 8b 54 24 68 0f 84 2e 02 00 00 48 89 RSP: 0018:ffffc90013e873a0 EFLAGS: 00000293 RAX: ffffffff820a16b0 RBX: ffffea0001927988 RCX: ffff88802f5e3c00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90013e87650 R08: ffffea0001927973 R09: 1ffffd4000324f2e R10: dffffc0000000000 R11: fffff94000324f2f R12: ffffea0001927980 R13: 80000000649e6007 R14: 00007fb570bd5000 R15: ffff88802892b5c0 unmap_single_vma mm/memory.c:1941 [inline] unmap_vmas+0x399/0x580 mm/memory.c:1985 exit_mmap+0x248/0xb50 mm/mmap.c:1284 __mmput+0x118/0x420 kernel/fork.c:1121 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x640/0x22e0 kernel/exit.c:943 do_group_exit+0x21c/0x2d0 kernel/exit.c:1104 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb57238e929 Code: Unable to access opcode bytes at 0x7fb57238e8ff. RSP: 002b:00007fb5731fb0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007fb5725b5fa8 RCX: 00007fb57238e929 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fb5725b5fac RBP: 00007fb5725b5fa0 R08: 7fffffffffffffff R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 00007fb5725b5fac R13: 0000000000000000 R14: 00007ffc86182e60 R15: 00007ffc86182f48 task:syz.0.4435 state:R running task stack:25160 pid:18843 tgid:18843 ppid:5832 task_flags:0x40004c flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6965 preempt_schedule+0xae/0xc0 kernel/sched/core.c:6989 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] zap_pte_range mm/memory.c:1765 [inline] zap_pmd_range mm/memory.c:1827 [inline] zap_pud_range mm/memory.c:1856 [inline] zap_p4d_range mm/memory.c:1877 [inline] unmap_page_range+0x3842/0x41c0 mm/memory.c:1898 unmap_single_vma mm/memory.c:1941 [inline] unmap_vmas+0x399/0x580 mm/memory.c:1985 exit_mmap+0x248/0xb50 mm/mmap.c:1284 __mmput+0x118/0x420 kernel/fork.c:1121 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x640/0x22e0 kernel/exit.c:943 do_group_exit+0x21c/0x2d0 kernel/exit.c:1104 __do_sys_exit_group kernel/exit.c:1115 [inline] __se_sys_exit_group kernel/exit.c:1113 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1113 x64_sys_call+0x21ba/0x21c0 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: 0033:0x7f40dd38e929 RSP: 002b:00007ffdfaefc298 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f40dd38e929 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffdfaefc2fc R08: 00000004faefc38f R09: 00000000000927c0 R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000002ea R13: 00000000000927c0 R14: 000000000009c0d8 R15: 00007ffdfaefc350 rcu: rcu_preempt kthread starved for 10502 jiffies! g74061 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:26664 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256 kthread+0x711/0x8a0 kernel/kthread.c:464 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: 0 UID: 0 PID: 18882 Comm: syz.6.4449 Not tainted 6.16.0-rc1-syzkaller-00203-g4774cfe3543a #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216 Code: 8b 3d f4 17 fa 0b 48 89 de 5b e9 f3 b0 58 00 cc cc cc 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 08 e0 9c 92 65 8b 15 d8 83 dc 10 81 e2 00 01 ff 00 RSP: 0018:ffffc900147c76d8 EFLAGS: 00000202 RAX: ffffffff81b4e850 RBX: ffff8880b863cb40 RCX: ffff888025383c00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900147c7840 R08: ffffffff8fa108f7 R09: 1ffffffff1f4211e R10: dffffc0000000000 R11: ffffffff81703110 R12: 1ffff110170e828d R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b8741468 FS: 0000000000000000(0000) GS:ffff888125c52000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2ee1dff8 CR3: 0000000051654000 CR4: 0000000000350ef0 Call Trace: csd_lock_wait kernel/smp.c:340 [inline] smp_call_function_many_cond+0xf80/0x12d0 kernel/smp.c:885 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:1361 [inline] flush_tlb_mm_range+0x6b1/0x12c0 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 exit_mmap+0x44c/0xb50 mm/mmap.c:1297 __mmput+0x118/0x420 kernel/fork.c:1121 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x640/0x22e0 kernel/exit.c:943 do_group_exit+0x21c/0x2d0 kernel/exit.c:1104 __do_sys_exit_group kernel/exit.c:1115 [inline] __se_sys_exit_group kernel/exit.c:1113 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1113 x64_sys_call+0x21ba/0x21c0 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: 0033:0x7f912ed8e929 Code: Unable to access opcode bytes at 0x7f912ed8e8ff. RSP: 002b:00007ffc87be5f88 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f912ed8e929 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffc87be5fec R08: 0000000487be607f R09: 00000000000927c0 R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000002aa R13: 00000000000927c0 R14: 000000000009c928 R15: 00007ffc87be6040