rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=9b3c/0/0x1 softirq=127795/127796 fqs=164 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P22270/1:b..l P22287/1:b..l P22280/1:b..l rcu: (detected by 0, t=10502 jiffies, g=143537, q=101 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:__lock_acquire+0x1c0/0x1a40 kernel/locking/lockdep.c:5174 Code: 00 04 00 41 c1 e1 13 44 09 f8 09 d0 8b 94 24 c0 00 00 00 44 09 c8 c1 e2 14 09 d0 8b 94 24 b0 00 00 00 c1 e2 15 09 d0 8b 53 20 <81> e2 ff 1f 00 00 09 d0 89 43 20 8b 84 24 b8 00 00 00 89 43 24 4c RSP: 0018:ffffc90000a08c18 EFLAGS: 00000006 RAX: 00000000000c4000 RBX: ffff88801eac3108 RCX: 0000000000000000 RDX: 00000000000c4000 RSI: ffff88801eac30e0 RDI: ffffffff9b94f688 RBP: ffff88801eac2540 R08: 0000000000000001 R09: 0000000000080000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888123edc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8eacb55690 CR3: 00000000463e9000 CR4: 00000000003526f0 Call Trace: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:166 debug_object_activate+0x144/0x4b0 lib/debugobjects.c:873 debug_hrtimer_activate kernel/time/hrtimer.c:485 [inline] debug_activate kernel/time/hrtimer.c:528 [inline] enqueue_hrtimer+0x75/0x2f0 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:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: d6 8b 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 c3 7e 10 00 fb f4 3c 4a 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197e00 EFLAGS: 00000242 RAX: 00000000003df997 RBX: ffff88801eac2540 RCX: ffffffff8bbb22d5 RDX: 0000000000000000 RSI: ffffffff8e1a5f23 RDI: ffffffff8c401680 RBP: ffffed1003d584a8 R08: 0000000000000001 R09: ffffed10170a678d R10: ffff8880b8533c6b R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 1ffff92000032fc4 R15: dffffc0000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:768 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 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x158 task:syz.4.6067 state:R running task stack:27256 pid:22280 tgid:22276 ppid:5619 task_flags:0x40054c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7234 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7413 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] zap_pte_range mm/memory.c:1964 [inline] zap_pmd_range mm/memory.c:2020 [inline] zap_pud_range mm/memory.c:2048 [inline] zap_p4d_range mm/memory.c:2069 [inline] __zap_vma_range+0x16f7/0x4a30 mm/memory.c:2109 unmap_vmas+0x299/0x5f0 mm/memory.c:2178 exit_mmap+0x1ef/0xa00 mm/mmap.c:1300 __mmput+0x12a/0x410 kernel/fork.c:1187 mmput+0x67/0x80 kernel/fork.c:1210 exit_mm kernel/exit.c:615 [inline] do_exit+0x8b1/0x2ae0 kernel/exit.c:997 do_group_exit+0xd5/0x2a0 kernel/exit.c:1152 get_signal+0x1ec7/0x21e0 kernel/signal.c:3046 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x139/0x6f0 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f027b59de99 RSP: 002b:00007f027c3f70e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f027b826098 RCX: 00007f027b59de99 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f027b826098 RBP: 00007f027b826090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f027b826128 R14: 00007ffccc47f1d0 R15: 00007ffccc47f2b8 task:syz.2.6069 state:R running task stack:25496 pid:22287 tgid:22286 ppid:5607 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7234 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7556 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x205/0xa00 kernel/entry/common.c:167 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:679 RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:422 [inline] RIP: 0010:unwind_next_frame+0xd02/0x2090 arch/x86/kernel/unwind_orc.c:614 Code: f6 ff ff 49 8d 76 f8 ba 08 00 00 00 4d 8d 7d 34 4c 89 ef 48 89 74 24 28 e8 2b f1 ff ff 84 c0 0f 84 4f f6 ff ff 48 8b 7c 24 28 f9 ea ff ff 48 89 ee 48 8b 4c 24 20 48 ba 00 00 00 00 00 fc ff RSP: 0018:ffffc9000ea36a78 EFLAGS: 00000202 RAX: ffffc9000ea38001 RBX: 0000000000000001 RCX: ffffffff91d1e9b0 RDX: ffffc9000ea37e01 RSI: ffffc9000ea37ec0 RDI: ffffc9000ea37ec0 RBP: ffffc9000ea36b30 R08: ffffffff91d1e9b4 R09: 0000000000000007 R10: 0000000000000200 R11: 00000000000162a3 R12: ffffc9000ea36b38 R13: ffffc9000ea36ae8 R14: ffffc9000ea37ec8 R15: ffffc9000ea36b1c arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x22b/0x6c0 mm/slub.c:6692 fsnotify_destroy_event fs/notify/notification.c:67 [inline] fsnotify_destroy_event+0x106/0x160 fs/notify/notification.c:50 inotify_handle_inode_event+0x5a1/0x6a0 fs/notify/inotify/inotify_fsnotify.c:129 fsnotify_handle_inode_event.isra.0+0x1e3/0x480 fs/notify/fsnotify.c:275 fsnotify_handle_event fs/notify/fsnotify.c:330 [inline] send_to_group fs/notify/fsnotify.c:378 [inline] fsnotify+0x1b45/0x3240 fs/notify/fsnotify.c:597 __fsnotify_parent+0x74f/0xd00 fs/notify/fsnotify.c:241 fsnotify_parent include/linux/fsnotify.h:96 [inline] fsnotify_path include/linux/fsnotify.h:113 [inline] fsnotify_file include/linux/fsnotify.h:127 [inline] fsnotify_file include/linux/fsnotify.h:116 [inline] fsnotify_access include/linux/fsnotify.h:429 [inline] __kernel_read+0x5b2/0xad0 fs/read_write.c:536 integrity_kernel_read+0x7e/0xb0 security/integrity/iint.c:28 ima_calc_file_hash_tfm+0x25e/0x350 security/integrity/ima/ima_crypto.c:222 ima_calc_file_hash+0x1e3/0x380 security/integrity/ima/ima_crypto.c:280 ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300 process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425 ima_file_mmap+0x1bb/0x1e0 security/integrity/ima/ima_main.c:523 security_mmap_file+0x278/0x9b0 security/security.c:2581 vm_mmap_pgoff+0xec/0x470 mm/util.c:575 ksys_mmap_pgoff+0x3cb/0x610 mm/mmap.c:606 __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+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f596079de99 RSP: 002b:00007f59615d5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f5960a25fa0 RCX: 00007f596079de99 RDX: 000000000200000c RSI: 0000000000003000 RDI: 0000200000001000 RBP: 00007f5960833eaf R08: 0000000000000005 R09: 0000000000002000 R10: 0000000000000013 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5960a26038 R14: 00007f5960a25fa0 R15: 00007fffef82fb38 task:syz.1.6064 state:R running task stack:26248 pid:22270 tgid:22269 ppid:5606 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7234 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7556 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x205/0xa00 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x17/0x70 kernel/kcov.c:217 Code: 03 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 8b 05 e5 df 59 12 48 8b 34 24 65 48 8b 15 c1 df 59 12 00 01 ff 00 74 1b f6 c4 01 74 07 a9 00 00 ff 00 74 05 c3 cc cc RSP: 0018:ffffc9000f46f590 EFLAGS: 00000246 RAX: 0000000080000000 RBX: ffffc9000f46f628 RCX: ffffc90003df2000 RDX: ffff8880282e0000 RSI: ffffffff8bb904d3 RDI: ffff8880282e0000 RBP: ffff888074e3bc82 R08: 0000000000000007 R09: 000000000000003f R10: 0000000000000015 R11: 0000000000000000 R12: 0000000000000015 R13: ffffc9000f46f640 R14: 0000000000000006 R15: ffffffff8248d560 xas_start+0x153/0x790 lib/xarray.c:201 xas_load+0x1e/0x5c0 lib/xarray.c:239 filemap_get_entry+0x115/0x450 mm/filemap.c:1901 __filemap_get_folio_mpol+0x5d/0x1320 mm/filemap.c:1947 __filemap_get_folio include/linux/pagemap.h:761 [inline] filemap_get_folio include/linux/pagemap.h:805 [inline] filemap_fault+0x1fa/0x3130 mm/filemap.c:3561 __do_fault+0x10b/0x440 mm/memory.c:5425 do_cow_fault mm/memory.c:5890 [inline] do_fault+0xeb2/0x1750 mm/memory.c:5996 do_pte_missing mm/memory.c:4566 [inline] handle_pte_fault mm/memory.c:6379 [inline] __handle_mm_fault+0x187d/0x2a00 mm/memory.c:6517 handle_mm_fault+0x37b/0xa30 mm/memory.c:6686 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x1178/0x32a0 mm/gup.c:1428 populate_vma_page_range+0x267/0x3f0 mm/gup.c:1860 __mm_populate+0x107/0x3a0 mm/gup.c:1963 do_mlock+0x3f0/0x7f0 mm/mlock.c:659 __do_sys_mlock mm/mlock.c:667 [inline] __se_sys_mlock mm/mlock.c:665 [inline] __x64_sys_mlock+0x59/0x80 mm/mlock.c:665 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: 0033:0x7fde56b9de99 RSP: 002b:00007fde57a9b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000095 RAX: ffffffffffffffda RBX: 00007fde56e25fa0 RCX: 00007fde56b9de99 RDX: 0000000000000000 RSI: 0000000000800000 RDI: 0000200000000000 RBP: 00007fde56c33eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fde56e26038 R14: 00007fde56e25fa0 R15: 00007ffd72942778 rcu: rcu_preempt kthread starved for 10174 jiffies! g143537 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:27432 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0xdd/0x2c0 kernel/sched/core.c:7326 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 07/16/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: d6 8b 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 c3 7e 10 00 fb f4 3c 4a 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff8e807e10 EFLAGS: 00000242 RAX: 000000000056cdcd RBX: ffffffff8e891480 RCX: ffffffff8bbb22d5 RDX: 0000000000000000 RSI: ffffffff8e1a5f23 RDI: ffffffff8c401680 RBP: fffffbfff1d12290 R08: 0000000000000001 R09: ffffed101708678d R10: ffff8880b8433c6b R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 1ffffffff1d00fc6 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888123ddc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc0d5a38bd7 CR3: 00000000379c9000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:768 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