Adjusting tsc more than 11% (8583078 vs 8464875) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=a1f4/1/0x4000000000000000 softirq=107598/107604 fqs=4 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17243/1:b..l rcu: (detected by 1, t=10502 jiffies, g=122145, q=2049 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 17261 Comm: syz.1.2238 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:97 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:115 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline] RIP: 0010:kasan_check_range+0x90/0x2c0 mm/kasan/generic.c:200 Code: 03 48 bb 01 00 00 00 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 3d 01 00 00 4c 89 cb 48 f7 d3 <4c> 01 fb 41 80 3b 00 0f 85 9e 01 00 00 49 ff c3 48 ff c3 75 ee e9 RSP: 0018:ffffc90000007da0 EFLAGS: 00000002 RAX: ffffffff81b3ea01 RBX: e00000000df4e090 RCX: ffffffff81b3eab2 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff9058fb78 RBP: ffff888034e59300 R08: ffffffff9058fb7f R09: 1ffffffff20b1f6f R10: dffffc0000000000 R11: fffffbfff20b1f6f R12: 0000000000000001 R13: ffffffff89e5ecf0 R14: fffffbfff20b1f70 R15: 1ffffffff20b1f6f FS: 00007f1a2d3826c0(0000) GS:ffff888124f0c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1a2a7f6d58 CR3: 000000003b936000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read include/linux/instrumented.h:82 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:650 [inline] cpu_online include/linux/cpumask.h:1232 [inline] trace_hrtimer_expire_entry include/trace/events/timer.h:261 [inline] __run_hrtimer kernel/time/hrtimer.c:2063 [inline] __hrtimer_run_queues+0x302/0xa10 kernel/time/hrtimer.c:2123 hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2242 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:handle_mounts fs/namei.c:1753 [inline] RIP: 0010:step_into_slowpath+0x4c2/0x820 fs/namei.c:2104 Code: db 00 00 00 e8 bf 9d 78 ff 48 8d 4b 58 48 8d 54 24 1f 48 8d 7c 24 40 44 89 ee 45 89 f0 e8 b6 b3 ff ff 41 89 c6 e9 af fc ff ff <48> 8b 7c 24 48 e8 74 a5 01 00 4c 8b 6c 24 40 48 8b 44 24 10 42 80 RSP: 0018:ffffc9000e907a20 EFLAGS: 00000282 RAX: ffffffff824ee4bc RBX: ffffc9000e907c20 RCX: 0000000000000000 RDX: ffff88802b87ddc0 RSI: 00000000fffffffe RDI: 0000000000000000 RBP: ffffc9000e907ac8 R08: ffff88801faf3e77 R09: 1ffff11003f5e7ce R10: dffffc0000000000 R11: ffffed1003f5e7cf R12: 1ffff92001d20f8b R13: 0000000000000000 R14: 00000000fffffffe R15: dffffc0000000000 step_into fs/namei.c:2152 [inline] open_last_lookups fs/namei.c:4780 [inline] path_openat+0x98e/0x1d60 fs/namei.c:4997 do_file_open+0x23e/0x4a0 fs/namei.c:5029 do_sys_openat2+0x115/0x200 fs/open.c:1417 do_sys_open fs/open.c:1423 [inline] __do_sys_openat fs/open.c:1439 [inline] __se_sys_openat fs/open.c:1434 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1434 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x510 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1a2c59e0d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1a2d382028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1a2c825fa0 RCX: 00007f1a2c59e0d9 RDX: 0000000000000000 RSI: 0000200000000180 RDI: ffffffffffffff9c RBP: 00007f1a2c635024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000041 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1a2c826038 R14: 00007f1a2c825fa0 R15: 00007ffd79a73de8 task:syz.9.2236 state:R running task stack:26920 pid:17243 tgid:17238 ppid:7748 task_flags:0x40044c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x1b2a/0x59a0 kernel/sched/core.c:7232 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7411 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline] _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:190 spin_unlock include/linux/spinlock.h:390 [inline] zap_pte_range mm/memory.c:2095 [inline] zap_pmd_range mm/memory.c:2151 [inline] zap_pud_range mm/memory.c:2179 [inline] zap_p4d_range mm/memory.c:2200 [inline] __zap_vma_range+0x40e1/0x4f80 mm/memory.c:2240 unmap_vmas+0x390/0x550 mm/memory.c:2309 exit_mmap+0x293/0x9f0 mm/mmap.c:1315 __mmput+0x118/0x420 kernel/fork.c:1193 exit_mm+0x221/0x2d0 kernel/exit.c:614 do_exit+0x6cd/0x2360 kernel/exit.c:996 do_group_exit+0x22d/0x2f0 kernel/exit.c:1151 get_signal+0x121b/0x12c0 kernel/signal.c:3039 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x138/0x770 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline] do_syscall_64+0x328/0x510 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f868299e0d9 RSP: 002b:00007f86837f40e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f8682c25fa8 RCX: 00007f868299e0d9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8682c25fa8 RBP: 00007f8682c25fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8682c26038 R14: 00007ffd1dc22940 R15: 00007ffd1dc22a28 rcu: rcu_preempt kthread starved for 10494 jiffies! g122145 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27496 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x1b2a/0x59a0 kernel/sched/core.c:7232 __schedule_loop kernel/sched/core.c:7309 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7324 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 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: 16879 Comm: udevd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:csd_lock_wait kernel/smp.c:363 [inline] RIP: 0010:csd_lock kernel/smp.c:396 [inline] RIP: 0010:smp_call_function_many_cond+0x61c/0x1500 kernel/smp.c:944 Code: b6 04 04 84 c0 0f 85 d5 03 00 00 44 8b 3b 44 89 fe 83 e6 01 31 ff e8 a3 50 0c 00 41 83 e7 01 75 07 e8 58 4c 0c 00 eb 3f f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 04 04 84 c0 75 0f f7 03 01 RSP: 0018:ffffc90006bbf420 EFLAGS: 00000293 RAX: ffffffff81bb38cc RBX: ffff8880b8643c88 RCX: ffff88802944ddc0 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90006bbf570 R08: ffff88802944f35f R09: 1ffff11005289e6b R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff110170c8791 R13: 0000000000000000 R14: ffff8880b8643c80 R15: 0000000000000001 FS: 00007fef5e172880(0000) GS:ffff88812500c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fef5e16e000 CR3: 0000000062b0a000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline] flush_tlb_mm_range+0x8fd/0x1090 arch/x86/mm/tlb.c:1435 dup_mmap+0x1758/0x1dc0 mm/mmap.c:1884 dup_mm kernel/fork.c:1549 [inline] copy_mm+0x11a/0x480 kernel/fork.c:1601 copy_process+0x1e75/0x43e0 kernel/fork.c:2313 kernel_clone+0x2d7/0x940 kernel/fork.c:2772 __do_sys_clone kernel/fork.c:2914 [inline] __se_sys_clone kernel/fork.c:2898 [inline] __x64_sys_clone+0x1b6/0x230 kernel/fork.c:2898 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x510 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fef5daf1636 Code: 89 df e8 6d e8 f6 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 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 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffc6eb2aeb0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007ffc6eb2aeb8 RCX: 00007fef5daf1636 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 000055b21df2e190 R08: 0000000000000000 R09: 000055b219de3140 R10: 00007fef5e172b50 R11: 0000000000000246 R12: 000055b21e1ba380 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000