rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=be2c/1/0x4000000000000000 softirq=119373/119376 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P13939/1:b..l rcu: (detected by 0, t=10506 jiffies, g=95553, q=481 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 17993 Comm: sed Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x10/0x20 kernel/kcov.c:300 Code: ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 40 0f b6 d6 40 0f b6 f7 01 00 00 00 e9 86 fe ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 RSP: 0018:ffffc90000a08e30 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff81f4d8ba RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff21b45d2 R10: ffffffff90da2e97 R11: ffffc90000a08ff8 R12: ffff88807acb4300 R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880b8528690 FS: 00007f045fbbec80(0000) GS:ffff888124416000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f045fd92a90 CR3: 000000005eae1000 CR4: 00000000003526f0 Call Trace: trace_hrtimer_start+0x6a/0x220 include/trace/events/timer.h:223 debug_activate kernel/time/hrtimer.c:529 [inline] enqueue_hrtimer+0x84/0x2f0 kernel/time/hrtimer.c:1109 __run_hrtimer kernel/time/hrtimer.c:2048 [inline] __hrtimer_run_queues+0x6ed/0x9c0 kernel/time/hrtimer.c:2096 hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:mas_next_slot+0x5d2/0x1960 lib/maple_tree.c:4142 Code: 7a f6 48 8b 0c 24 48 be 00 00 00 00 00 fc ff df 48 89 c8 83 e1 07 48 c1 e8 03 0f b6 04 30 38 c8 7f 08 84 c0 0f 85 78 10 00 00 <48> 8b 4c 24 20 45 0f b6 6f 4d 48 be 00 00 00 00 00 fc ff df 48 89 RSP: 0018:ffffc90004077480 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff888022bf0c00 RCX: 0000000000000005 RDX: ffff888027bc8000 RSI: dffffc0000000000 RDI: ffff888027bc8000 RBP: 0000000000000001 R08: 0000000000000006 R09: 00007f045fc85fff R10: ffffffffffffffff R11: 00007f045fc84fff R12: 00007f045fc85fff R13: ffffc90004077608 R14: ffffffffffffffff R15: ffffc900040775c0 mas_find+0x2ad/0x740 lib/maple_tree.c:5389 vma_next include/linux/mm.h:1640 [inline] validate_mm+0x11d/0x4e0 mm/vma.c:653 __split_vma+0xa7f/0xda0 mm/vma.c:570 split_vma mm/vma.c:599 [inline] vma_modify+0x12ad/0x25c0 mm/vma.c:1699 vma_modify_flags+0x257/0x3d0 mm/vma.c:1719 mprotect_fixup+0x27a/0xe30 mm/mprotect.c:789 do_mprotect_pkey+0xa4b/0xef0 mm/mprotect.c:967 __do_sys_mprotect mm/mprotect.c:988 [inline] __se_sys_mprotect mm/mprotect.c:985 [inline] __x64_sys_mprotect+0x78/0xc0 mm/mprotect.c:985 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f045ff552c7 Code: 89 3d fd 3f 01 00 eb 90 0f 1f 00 f7 d8 89 05 f0 3f 01 00 48 c7 c0 ff ff ff ff eb 91 0f 1f 80 00 00 00 00 b8 0a 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8d 0d c9 3f 01 00 f7 d8 89 01 48 83 RSP: 002b:00007ffdcf90fbb8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007f045ff2a050 RCX: 00007f045ff552c7 RDX: 0000000000000001 RSI: 0000000000001000 RDI: 00007f045fc74000 RBP: 00007ffdcf90fe80 R08: 0000000000000000 R09: 00007f045fcc6870 R10: 00007f045ff2a050 R11: 0000000000000206 R12: 0000000000000010 R13: 00000199c71e33f1 R14: 0000000000000000 R15: 00007f045ff69310 task:syz-executor state:R running task stack:23960 pid:13939 tgid:13939 ppid:13936 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7228 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7409 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+0x3e/0x50 kernel/locking/spinlock.c:190 spin_unlock include/linux/spinlock.h:390 [inline] copy_pte_range mm/memory.c:1347 [inline] copy_pmd_range mm/memory.c:1408 [inline] copy_pud_range mm/memory.c:1445 [inline] copy_p4d_range mm/memory.c:1469 [inline] copy_page_range+0x1c1f/0x5b20 mm/memory.c:1555 dup_mmap+0xd44/0x21b0 mm/mmap.c:1840 dup_mm kernel/fork.c:1538 [inline] copy_mm kernel/fork.c:1590 [inline] copy_process+0x4588/0x7ff0 kernel/fork.c:2288 kernel_clone+0x176/0x9d0 kernel/fork.c:2746 __do_sys_clone+0xd9/0x120 kernel/fork.c:2887 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f360bbc58d2 RSP: 002b:00007ffe58367c90 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007ffe58367c90 RCX: 00007f360bbc58d2 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007ffe58367e1c R08: 0000000000000000 R09: 0000000000000001 R10: 0000555561f267d0 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000000927c0 R14: 000000000009765b R15: 00007ffe58367e70 rcu: rcu_preempt kthread starved for 10506 jiffies! g95553 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:28416 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7322 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 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: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: 86 88 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 23 c8 14 00 fb f4 fc 48 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff8e407e10 EFLAGS: 00000246 RAX: 0000000003d6fd74 RBX: ffffffff8e491480 RCX: ffffffff8b96d2d5 RDX: 0000000000000001 RSI: ffffffff8c1e6100 RDI: ffffffff81de2aa7 RBP: fffffbfff1c92290 R08: 0000000000000000 R09: ffffed101708678d R10: ffff8880b8433c6b R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 1ffffffff1c80fc6 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888124316000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f15617ea540 CR3: 000000007f67f000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x3a7/0x5b0 kernel/sched/idle.c:355 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454 rest_init+0x251/0x260 init/main.c:717 start_kernel+0x48e/0x490 init/main.c:1175 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x158