rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9724/1:b..l P9788/1:b..l rcu: (detected by 1, t=10502 jiffies, g=32325, q=880 ncpus=2) task:syz.5.1031 state:R running task stack:26504 pid:9788 tgid:9787 ppid:6229 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872 Code: b4 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 22 be ee 0e 0f 82 74 02 00 00 8b 35 ba ee ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 39 b4 18 12 0f 85 ad 02 00 00 48 83 c4 RSP: 0018:ffffc9000bfd7508 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e3c96a0 RCX: 00000000638649d5 RDX: 0000000000000000 RSI: ffffffff8daa845f RDI: ffffffff8bf2b480 RBP: 0000000000000002 R08: 00000000ecffd74e R09: 00000000eecffd74 R10: 0000000000000002 R11: ffff8880784baff0 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] is_bpf_text_address+0x36/0x1a0 kernel/bpf/core.c:744 kernel_text_address kernel/extable.c:125 [inline] kernel_text_address+0x8d/0x100 kernel/extable.c:94 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x59/0xa0 arch/x86/kernel/unwind_orc.c:385 arch_stack_walk+0xa6/0x100 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5657 [inline] __kmalloc_node_noprof+0x355/0x930 mm/slub.c:5663 kmalloc_array_node_noprof include/linux/slab.h:1075 [inline] alloc_slab_obj_exts+0x43/0xf0 mm/slub.c:2123 account_slab mm/slub.c:3202 [inline] allocate_slab mm/slub.c:3267 [inline] new_slab+0x353/0x430 mm/slub.c:3302 ___slab_alloc+0xe18/0x1c90 mm/slub.c:4656 __kmem_cache_alloc_bulk+0x1fb/0x6c0 mm/slub.c:7431 kmem_cache_alloc_bulk_noprof+0x4e1/0x800 mm/slub.c:7497 __io_alloc_req_refill+0x9d/0x5e0 io_uring/io_uring.c:1026 io_alloc_req io_uring/io_uring.h:562 [inline] io_submit_sqes+0xf94/0x28e0 io_uring/io_uring.c:2424 __do_sys_io_uring_enter+0xd6b/0x1630 io_uring/io_uring.c:3285 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3eb198f749 RSP: 002b:00007f3eb284a038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007f3eb1be5fa0 RCX: 00007f3eb198f749 RDX: 000000000000f9d0 RSI: 0000000000002b93 RDI: 0000000000000004 RBP: 00007f3eb1a13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3eb1be6038 R14: 00007f3eb1be5fa0 R15: 00007ffc04c372a8 task:syz.4.1014 state:R running task stack:24008 pid:9724 tgid:9724 ppid:5815 task_flags:0x40064c flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:unwind_next_frame+0x522/0x20b0 arch/x86/kernel/unwind_orc.c:520 Code: 00 00 fc ff df 4c 8d 79 05 4c 89 fa 48 c1 ea 03 0f b6 04 02 4c 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 28 15 00 00 0f b6 41 05 <83> e0 07 0f 84 53 fe ff ff 3c 01 0f 84 7b fe ff ff 4c 8d 41 04 4c RSP: 0018:ffffc9000c006f38 EFLAGS: 00000246 RAX: 0000000000000002 RBX: 0000000000000001 RCX: ffffffff91261edc RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffffff90a1022c RBP: ffffc9000c006ff0 R08: ffffffff91261f0c R09: 00000000ffffffff R10: 0000000000000002 R11: 000000000000a963 R12: ffffc9000c006ff8 R13: ffffc9000c006fa8 R14: ffffc9000c006fdd R15: ffffffff91261ee1 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:165 __reset_page_owner+0x84/0x1a0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1406 [inline] free_unref_folios+0xa22/0x1610 mm/page_alloc.c:3000 folios_put_refs+0x4be/0x750 mm/swap.c:1002 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x58f/0x1140 mm/shmem.c:1137 shmem_truncate_range mm/shmem.c:1249 [inline] shmem_evict_inode+0x39e/0xbe0 mm/shmem.c:1379 evict+0x3c2/0xad0 fs/inode.c:837 iput_final fs/inode.c:1951 [inline] iput.part.0+0x621/0x1190 fs/inode.c:2003 iput+0x35/0x40 fs/inode.c:1966 dentry_unlink_inode+0x29c/0x480 fs/dcache.c:467 __dentry_kill+0x1d0/0x600 fs/dcache.c:670 finish_dput+0x76/0x480 fs/dcache.c:879 dput.part.0+0x451/0x570 fs/dcache.c:928 dput+0x1f/0x30 fs/dcache.c:920 __fput+0x51c/0xb70 fs/file_table.c:476 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x87f/0x2bd0 kernel/exit.c:971 do_group_exit+0xd3/0x2a0 kernel/exit.c:1112 get_signal+0x2671/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop kernel/entry/common.c:75 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline] irqentry_exit+0x38a/0x8c0 kernel/entry/common.c:196 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f52f698f751 RSP: 002b:fffffffffffffe70 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f52f6be6090 RCX: 00007f52f698f749 RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000 RBP: 00007f52f6a13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f52f6be6128 R14: 00007f52f6be6090 R15: 00007ffc88b7d9f8 rcu: rcu_preempt kthread starved for 10593 jiffies! g32325 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:28320 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 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+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 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: 9778 Comm: syz.1.1029 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:37 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline] RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline] RIP: 0010:native_apic_msr_write arch/x86/include/asm/apic.h:212 [inline] RIP: 0010:native_apic_msr_write+0x28/0x40 arch/x86/include/asm/apic.h:206 Code: 90 90 f3 0f 1e fa 8d 87 30 ff ff ff 83 e0 ef 74 20 89 f8 83 e0 ef 83 f8 20 74 16 c1 ef 04 31 d2 89 f0 8d 8f 00 08 00 00 0f 30 <66> 90 e9 91 06 10 0a e9 8c 06 10 0a 89 f6 31 d2 89 cf e9 a1 ef 76 RSP: 0018:ffffc90000007ec8 EFLAGS: 00000046 RAX: 000000000000207a RBX: ffff8880b8423f40 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000000207a RDI: 0000000000000038 RBP: 000000000000207a R08: 0000000000000005 R09: 000000000000003f R10: 0000000000000020 R11: ffff8880330ad4b0 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000020 R15: ffff8880b8428440 FS: 000055557b095500(0000) GS:ffff8881248f5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3eb27c4d58 CR3: 00000000575db000 CR4: 00000000003526f0 Call Trace: apic_write arch/x86/include/asm/apic.h:409 [inline] lapic_next_event+0x10/0x20 arch/x86/kernel/apic/apic.c:418 clockevents_program_event+0x26e/0x370 kernel/time/clockevents.c:334 tick_program_event+0xa9/0x140 kernel/time/tick-oneshot.c:48 hrtimer_interrupt+0x3e9/0x8e0 kernel/time/hrtimer.c:1916 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x10b/0x3c0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 Code: 90 f3 0f 1e fa 53 48 8b 74 24 08 48 89 fb 48 83 c7 18 e8 7a 0e 1f f6 48 89 df e8 32 61 1f f6 e8 9d 24 4c f6 fb bf 01 00 00 00 42 64 0f f6 65 8b 05 9b c9 37 08 85 c0 74 06 5b e9 01 4d 00 00 RSP: 0018:ffffc90004f3fca0 EFLAGS: 00000202 RAX: 000000000a916d3b RBX: ffff8880311cc0c0 RCX: ffffffff81c70a2f RDX: 0000000000000000 RSI: ffffffff8dace4f3 RDI: 0000000000000001 RBP: ffff8880311cc4c0 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff9088b9d7 R11: ffff8880330ad4b0 R12: 0000000000000000 R13: 0000000000000021 R14: 0000000000000400 R15: ffff8880311cc0c0 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x1e6a/0x26d0 kernel/signal.c:3037 arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x8c/0x540 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6819f8f749 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:00007ffe320f83e8 EFLAGS: 00000246 RAX: fffffffffffffffc RBX: 0000000000059cf6 RCX: 00007f6819f8f749 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f681a1e618c RBP: 0000000000000032 R08: 00007f681ae7b000 R09: 0000001b320f86df R10: 00007ffe320f84e0 R11: 0000000000000246 R12: 00007f681a1e618c R13: 00007ffe320f84e0 R14: 0000000000059d28 R15: 00007ffe320f8500