rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8082/1:b..l rcu: (detected by 1, t=10504 jiffies, g=24705, q=319 ncpus=2) task:syz.1.530 state:R running task stack:26536 pid:8082 tgid:8081 ppid:5810 task_flags:0x400140 flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6929 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7256 irqentry_exit+0x36/0x90 kernel/entry/common.c:211 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:kasan_check_byte include/linux/kasan.h:401 [inline] RIP: 0010:lock_acquire kernel/locking/lockdep.c:5842 [inline] RIP: 0010:lock_acquire+0xef/0x350 kernel/locking/lockdep.c:5825 Code: 41 57 44 89 e9 44 89 f2 48 89 de e8 ab d0 fe ff 5f 41 58 65 ff 0d f1 e5 08 12 0f 85 4f ff ff ff e8 76 1c 93 ff e9 45 ff ff ff <48> 8b 74 24 68 48 89 df e8 d4 96 8c 00 8b 0d f2 7c e9 0e 85 c9 0f RSP: 0018:ffffc9000445ec60 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffffff8e3c4760 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff8dcd5ee0 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 00000000000117c3 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 save_stack+0x160/0x1f0 mm/page_owner.c:156 __set_page_owner+0x91/0x560 mm/page_owner.c:332 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845 prep_new_page mm/page_alloc.c:1853 [inline] get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3879 __alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5178 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2435 shmem_alloc_folio+0x135/0x160 mm/shmem.c:1870 shmem_alloc_and_add_folio+0x494/0xc20 mm/shmem.c:1912 shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2535 shmem_fault+0x1fe/0xa30 mm/shmem.c:2736 __do_fault+0x10d/0x490 mm/memory.c:5281 do_read_fault mm/memory.c:5716 [inline] do_fault mm/memory.c:5850 [inline] do_pte_missing+0xf4a/0x3ba0 mm/memory.c:4362 handle_pte_fault mm/memory.c:6195 [inline] __handle_mm_fault+0x1556/0x2aa0 mm/memory.c:6336 handle_mm_fault+0x589/0xd10 mm/memory.c:6505 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x54e/0x3530 mm/gup.c:1428 populate_vma_page_range+0x267/0x3f0 mm/gup.c:1860 __mm_populate+0x1d8/0x380 mm/gup.c:1963 mm_populate include/linux/mm.h:3478 [inline] vm_mmap_pgoff+0x37f/0x470 mm/util.c:586 ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:604 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f129818f749 RSP: 002b:00007f1298fa0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f12983e5fa0 RCX: 00007f129818f749 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007f1298213f91 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f12983e6038 R14: 00007f12983e5fa0 R15: 00007ffd075168e8 rcu: rcu_preempt kthread timer wakeup didn't happen for 10465 jiffies! g24705 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=16125 rcu: rcu_preempt kthread starved for 10466 jiffies! g24705 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28744 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7026 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8084 Comm: syz.0.531 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:98 [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+0x159/0x1b0 mm/kasan/generic.c:200 Code: 2c 48 89 c2 48 85 c0 75 ad 48 89 da 4c 89 d8 4c 29 da e9 46 ff ff ff 48 85 d2 74 18 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 0a <80> 38 00 74 f2 e9 75 ff ff ff 5b b8 01 00 00 00 5d 41 5c c3 cc cc RSP: 0018:ffffc90000007cd8 EFLAGS: 00000082 RAX: ffffed1006a37e5d RBX: ffffed1006a37e5e RCX: ffffffff8199136d RDX: ffffed1006a37e5e RSI: 0000000000000004 RDI: ffff8880351bf2e8 RBP: ffffed1006a37e5d R08: 0000000000000001 R09: ffffed1006a37e5d R10: ffff8880351bf2eb R11: 0000000000000001 R12: ffff8880351bf2f0 R13: ffff8880351bf2f8 R14: ffff8880351bf340 R15: ffffffff896c8db0 FS: 0000555582ea5500(0000) GS:ffff888124a05000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2f150e CR3: 000000007d569000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1300 [inline] queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] do_raw_spin_lock+0x11d/0x2b0 kernel/locking/spinlock_debug.c:116 spin_lock include/linux/spinlock.h:351 [inline] advance_sched+0xd9/0xc80 net/sched/sch_taprio.c:929 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x202/0xad0 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] __sysvec_apic_timer_interrupt+0x10b/0x3f0 arch/x86/kernel/apic/apic.c:1058 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:preempt_schedule_irq+0x4c/0x90 kernel/sched/core.c:7256 Code: df 55 65 48 8b 2d ac b2 3f 08 53 48 89 eb 48 c1 eb 03 48 01 c3 bf 01 00 00 00 e8 4f 96 27 f6 e8 1a ec 62 f6 fb bf 01 00 00 00 af 99 ff ff 9c 58 fa f6 c4 02 75 1e bf 01 00 00 00 e8 3d 21 27 RSP: 0018:ffffc90003077988 EFLAGS: 00000206 RAX: 00000000000038b7 RBX: ffffed10053f7490 RCX: 0000000000000006 RDX: 0000000000000000 RSI: ffffffff8da2c59c RDI: 0000000000000001 RBP: ffff888029fba480 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff908216d7 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 irqentry_exit+0x36/0x90 kernel/entry/common.c:211 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:704 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872 Code: e6 08 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 22 4d e9 0e 0f 82 74 02 00 00 8b 35 9a 7d e9 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 39 e6 08 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc90003077a58 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e290d00 RCX: 00000000ffccd1a4 RDX: 0000000000000000 RSI: ffffffff8da06b82 RDI: ffffffff8bf073c0 RBP: 0000000000000000 R08: 830805f4d04cc640 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 sched_submit_work kernel/sched/core.c:6967 [inline] schedule+0x21c/0x3a0 kernel/sched/core.c:7025 futex_do_wait+0x88/0x180 kernel/futex/waitwake.c:358 __futex_wait+0x1b8/0x2f0 kernel/futex/waitwake.c:687 futex_wait+0xe8/0x380 kernel/futex/waitwake.c:715 do_futex+0x229/0x350 kernel/futex/syscalls.c:130 __do_sys_futex kernel/futex/syscalls.c:207 [inline] __se_sys_futex kernel/futex/syscalls.c:188 [inline] __x64_sys_futex+0x1e0/0x4c0 kernel/futex/syscalls.c:188 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcbcef8f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff5956afa8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 000000000003b765 RCX: 00007fcbcef8f749 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fcbcf1e609c RBP: 0000000000000032 R08: 00007fcbcfd36000 R09: 0000001c5956b29f R10: 00007fff5956b0a0 R11: 0000000000000246 R12: 00007fcbcf1e609c R13: 00007fff5956b0a0 R14: 000000000003b797 R15: 00007fff5956b0c0