rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6511/1:b..l P6514/1:b..l P6501/1:b..l (detected by 1, t=10503 jiffies, g=27601, q=127 ncpus=2) task:rm state:R running task stack:24336 pid:6501 ppid:6450 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696 RIP: 0010:__sanitizer_cov_trace_switch+0x4f/0xe0 kernel/kcov.c:348 Code: 48 85 c0 0f 84 a7 00 00 00 41 57 41 56 41 54 53 48 8b 0c cd b8 26 90 8a 48 8b 54 24 20 65 4c 8b 05 76 f5 7f 7e 45 31 c9 eb 08 <49> ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d 64 f5 7f 7e 41 RSP: 0018:ffffc90004867198 EFLAGS: 00000293 RAX: 0000000000000003 RBX: ffff888027986a0c RCX: 0000000000000005 RDX: ffffffff8a1a15ef RSI: ffffffff8e08acc0 RDI: 0000000000000001 RBP: ffffc90004867370 R08: ffff888046418000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff888027986a00 R14: 0000000000000080 R15: 0000000000000001 ma_pivots lib/maple_tree.c:632 [inline] mas_validate_child_slot lib/maple_tree.c:7071 [inline] mt_validate+0x12af/0x4cb0 lib/maple_tree.c:7243 validate_mm_mt+0xe2/0x440 mm/mmap.c:295 validate_mm+0xe1/0x2e0 mm/mmap.c:332 __vma_adjust+0x1855/0x1cd0 mm/mmap.c:879 vma_adjust include/linux/mm.h:2810 [inline] __split_vma+0x3a7/0x500 mm/mmap.c:-1 do_mas_align_munmap+0x397/0x12b0 mm/mmap.c:2480 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __mmap_region mm/mmap.c:2698 [inline] mmap_region+0x6e0/0x1ca0 mm/mmap.c:2916 do_mmap+0x964/0xfd0 mm/mmap.c:1436 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f022899e242 RSP: 002b:00007fff4c5a9298 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f02286b2000 RCX: 00007f022899e242 RDX: 0000000000000005 RSI: 0000000000008000 RDI: 00007f02286b2000 RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000003000 R10: 0000000000000812 R11: 0000000000000206 R12: 00007fff4c5a92e8 R13: 00007f022897b580 R14: 00007fff4c5a9710 R15: 00000fffe98b5256 task:syz.2.558 state:R running task stack:28656 pid:6514 ppid:4269 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696 RIP: 0010:__set_page_owner_handle+0xb6/0x3c0 mm/page_owner.c:168 Code: 24 10 89 de e8 fb 6f a6 ff 44 39 f3 0f 84 d8 02 00 00 48 8b 1d 8b 41 e7 0a 49 8d 7c 1f 08 48 89 f8 48 c1 e8 03 42 0f b6 04 28 <84> c0 0f 85 da 01 00 00 4c 01 fb 8b 44 24 08 89 43 08 48 89 d8 48 RSP: 0000:ffffc900048078b8 EFLAGS: 00000a02 RAX: 0000000000000000 RBX: 0000000000000008 RCX: 0000000000000000 RDX: ffff88807e068000 RSI: 0000000000000001 RDI: ffff88801b008dd0 RBP: 0000000000000000 R08: dffffc0000000000 R09: 1ffffffff215ea48 R10: dffffc0000000000 R11: fffffbfff215ea49 R12: 0000000000000001 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88801b008dc0 __set_page_owner+0x41/0x60 mm/page_owner.c:195 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559 prep_new_page mm/page_alloc.c:2566 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5643 __folio_alloc+0xe/0x30 mm/page_alloc.c:5675 vma_alloc_folio+0x4a3/0x900 mm/mempolicy.c:2243 alloc_page_vma include/linux/gfp.h:284 [inline] do_anonymous_page mm/memory.c:4189 [inline] handle_pte_fault mm/memory.c:5027 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x22b1/0x3ee0 mm/memory.c:5292 do_user_addr_fault+0x51f/0xb10 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7fa11d94abdf RSP: 002b:00007fa11e7edff0 EFLAGS: 00010246 RAX: 00007fa11e7ee0d0 RBX: 0000000000020000 RCX: 00007fa11e7edff0 RDX: 00007fa11da4e9d3 RSI: 0000000000000023 RDI: 00007fa11e7ee0d0 RBP: 00007fa11e7cf000 R08: 0000000000000000 R09: 00007ffd55a9f1d7 R10: 0000000000000008 R11: 0000000000000202 R12: 00007fa11e7ee0d0 R13: 000000000000000b R14: 00007ffd55a9f0f0 R15: 00007ffd55a9f1d8 task:syz-executor state:R running task stack:29008 pid:6511 ppid:4268 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6731 preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6755 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] filemap_map_pages+0xf06/0x11c0 mm/filemap.c:3531 do_fault_around mm/memory.c:4598 [inline] do_read_fault mm/memory.c:4624 [inline] do_fault mm/memory.c:4758 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x2991/0x3ee0 mm/memory.c:5292 do_user_addr_fault+0x51f/0xb10 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f1e9cb3ec40 RSP: 002b:00007ffd53661e78 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 00007ffd53661e80 RCX: 00007f1e9cbc510c RDX: 0000000000000000 RSI: 0000000000000018 RDI: 00005555884e47e0 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 R10: 00005555884e47d0 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000000927c0 R14: 00000000000440fe R15: 00007ffd53662060 rcu: rcu_preempt kthread starved for 9907 jiffies! g27601 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:28016 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:__lock_acquire+0x12fc/0x7d10 kernel/locking/lockdep.c:5046 Code: 00 89 c3 81 e3 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 40 52 af 90 be 08 00 00 00 e8 1c 0b 6f 00 48 0f a3 1d d4 fa 4a 0f <73> 1a 48 8d 04 5b c1 e0 06 48 8d 98 00 d1 47 90 49 b8 00 00 00 00 RSP: 0018:ffffc900000079c0 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 0000000000000049 RCX: ffffffff81645764 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90af5248 RBP: ffffc90000007c10 R08: ffffffff90af524f R09: 1ffffffff215ea49 R10: dffffc0000000000 R11: fffffbfff215ea4a R12: 00000000dea32d42 R13: 000000000000404a R14: 000000009d9a9a6b R15: ffffffff8c8bd210 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f46138fa05c CR3: 000000007bed1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 seqcount_lockdep_reader_access+0xcd/0x1d0 include/linux/seqlock.h:102 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] ktime_get+0x7b/0x270 kernel/time/timekeeping.c:848 clockevents_program_event+0xe2/0x310 kernel/time/clockevents.c:326 hrtimer_interrupt+0x59d/0x9c0 kernel/time/hrtimer.c:1886 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742 Code: 48 89 df e8 27 c3 9c f7 e9 44 ff ff ff e8 3d 07 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d 77 0c 50 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48 RSP: 0018:ffffffff8c807d88 EFLAGS: 000002c6 RAX: c8d7e592b4b70000 RBX: ffffffff8a36a2b7 RCX: c8d7e592b4b70000 RDX: 0000000000000001 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0de0 RBP: ffffffff8c807ec0 R08: ffff8880b8e3580b R09: 1ffff110171c6b01 R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 1ffffffff1900fbc R13: dffffc0000000000 R14: ffffffff8c8bc740 R15: 0000000000000000 default_idle_call+0x84/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x20d/0x5a0 kernel/sched/idle.c:303 cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401 rest_init+0x2dc/0x300 init/main.c:745 arch_call_rest_init+0xa/0xa init/main.c:905 start_kernel+0x493/0x53c init/main.c:1152 secondary_startup_64_no_verify+0xcf/0xdb sched: RT throttling activated