rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9159/1:b..l rcu: (detected by 1, t=10505 jiffies, g=47889, q=866 ncpus=2) task:syz-executor state:R running task stack:22320 pid:9159 tgid:9159 ppid:9134 task_flags:0x40014c flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7556 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:679 RIP: 0010:srso_alias_safe_ret+0x5/0x7 arch/x86/lib/retpoline.S:213 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 48 8d 64 24 08 cc e8 f4 ff ff ff 0f 0b cc cc cc cc cc cc cc cc cc cc cc cc cc RSP: 0018:ffffc90003026f90 EFLAGS: 00000293 RAX: ffffffff823f9eef RBX: 000000000003f527 RCX: ffff88807d823e00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000003f527 RBP: 0000000000000000 R08: ffffffff823fa84c R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb59c60 R12: 000000000003f527 R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff823fa84c _static_cpu_has arch/x86/include/asm/cpufeature.h:101 [inline] __nr_to_section include/linux/mmzone.h:2050 [inline] __pfn_to_section include/linux/mmzone.h:2187 [inline] lookup_page_ext mm/page_ext.c:255 [inline] page_ext_lookup+0x15f/0x180 mm/page_ext.c:513 page_ext_iter_begin include/linux/page_ext.h:137 [inline] __page_table_check_zero+0x16b/0x430 mm/page_table_check.c:139 page_table_check_free include/linux/page_table_check.h:46 [inline] __free_pages_prepare mm/page_alloc.c:1407 [inline] free_unref_folios+0xd94/0x14a0 mm/page_alloc.c:3011 folios_put_refs+0x9e9/0xb30 mm/swap.c:1057 folio_batch_release include/linux/folio_batch.h:101 [inline] shmem_undo_range+0x4e6/0x15d0 mm/shmem.c:1149 shmem_truncate_range mm/shmem.c:1277 [inline] shmem_evict_inode+0x280/0xa80 mm/shmem.c:1407 evict+0x624/0xb50 fs/inode.c:825 dentry_kill+0x1b9/0x880 fs/dcache.c:826 shrink_kill fs/dcache.c:1275 [inline] shrink_dentry_list+0x209/0x310 fs/dcache.c:1292 shrink_dcache_tree+0xe7/0x410 fs/dcache.c:1725 do_one_tree+0x18/0xa0 fs/dcache.c:1795 shrink_dcache_for_umount+0x111/0x500 fs/dcache.c:1812 generic_shutdown_super+0x6f/0x2d0 fs/super.c:625 kill_anon_super+0x3b/0x70 fs/super.c:1232 deactivate_locked_super+0xbc/0x130 fs/super.c:477 cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x73a/0x2360 kernel/exit.c:1004 do_group_exit+0x22d/0x2f0 kernel/exit.c:1147 __do_sys_exit_group kernel/exit.c:1158 [inline] __se_sys_exit_group kernel/exit.c:1156 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1156 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f27c0b9de59 RSP: 002b:00007ffd1104f9d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f27c0c332d6 RCX: 00007f27c0b9de59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000075 R08: 0000000000000000 R09: 00007f27c0c332ca R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd11050c90 R13: 00007f27c0c332ca R14: 00005555780cf4e8 R15: 00007ffd11052e50 rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g47889 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=20098 rcu: rcu_preempt kthread starved for 10505 jiffies! g47889 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:28192 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325 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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 10468 Comm: cmp Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026 RIP: 0010:lock_is_held_type+0x5/0x150 kernel/locking/lockdep.c:5925 Code: 48 c7 c6 4c 84 42 8e 67 48 0f b9 3a 90 eb ce 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <41> 57 41 56 41 55 41 54 53 bb ff ff ff ff 83 3d 96 b2 88 04 00 0f RSP: 0018:ffffc90000007d90 EFLAGS: 00000086 RAX: 1ffff110170c5060 RBX: ffff8880b8628300 RCX: 0000000000010000 RDX: ffff88803623be00 RSI: 00000000ffffffff RDI: ffff8880b86281d8 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000000fac R12: 0000000000000001 R13: dffffc0000000000 R14: ffff888078f80300 R15: 0000000000000000 FS: 00007f02d6147c80(0000) GS:ffff888124f58000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f02d64af000 CR3: 0000000038b3b000 CR4: 0000000000350ef0 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] enqueue_hrtimer+0x79/0x2c0 kernel/time/hrtimer.c:1107 __run_hrtimer kernel/time/hrtimer.c:2048 [inline] __hrtimer_run_queues+0x4ce/0xa10 kernel/time/hrtimer.c:2096 hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215 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:__sanitizer_cov_trace_switch+0x61/0xf0 kernel/kcov.c:350 Code: 00 00 00 41 57 41 56 41 54 53 48 8d 0c 4d 01 00 00 00 48 8b 54 24 20 65 4c 8b 05 f2 07 a6 11 45 31 c9 eb 08 49 ff c1 4c 39 c8 <74> 77 4e 8b 54 ce 10 65 44 8b 1d 00 08 a6 11 41 81 e3 00 01 ff 00 RSP: 0018:ffffc90005087578 EFLAGS: 00000202 RAX: 0000000000000006 RBX: 1ffff92000a10ed5 RCX: 0000000000000005 RDX: ffffffff8bc78ec1 RSI: ffffffff903d8d60 RDI: 0000000000000000 RBP: ffffffffffffffff R08: ffff88803623be00 R09: 0000000000000005 R10: 0000000000000006 R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffc90005087660 R15: ffffc900050876a8 mas_find_setup lib/maple_tree.c:5292 [inline] mas_find+0x51/0xcf0 lib/maple_tree.c:5385 vma_next include/linux/mm.h:1640 [inline] validate_mm+0xff/0x4f0 mm/vma.c:653 __split_vma+0x916/0xa50 mm/vma.c:570 split_vma mm/vma.c:599 [inline] vma_modify+0x93a/0x1c70 mm/vma.c:1699 vma_modify_flags+0x24b/0x330 mm/vma.c:1719 mprotect_fixup+0x624/0xb10 mm/mprotect.c:789 do_mprotect_pkey+0x9d3/0xcd0 mm/mprotect.c:967 __do_sys_mprotect mm/mprotect.c:988 [inline] __se_sys_mprotect mm/mprotect.c:985 [inline] __x64_sys_mprotect+0x80/0x90 mm/mprotect.c:985 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f02d64de2c7 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:00007ffff508fbb8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007f02d64b20c0 RCX: 00007f02d64de2c7 RDX: 0000000000000001 RSI: 0000000000003000 RDI: 00007f02d64ae000 RBP: 00007ffff508fe80 R08: 0000000000000000 R09: 00007f02d642fbf7 R10: 00007f02d64b20c0 R11: 0000000000000206 R12: 0000000000000008 R13: 00000156128503d0 R14: 0000000000000000 R15: 00007f02d64f2310