rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=25ac/1/0x4000000000000000 softirq=122201/122203 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P23254/1:b..l P23252/1:b..l rcu: (detected by 0, t=10502 jiffies, g=135017, q=307 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 23225 Comm: syz.9.5320 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:__sanitizer_cov_trace_const_cmp4+0x0/0x90 kernel/kcov.c:313 Code: 11 10 48 89 74 11 18 48 89 44 11 20 e9 14 28 49 ff cc 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 15 e8 26 a6 11 65 8b 0d 09 27 a6 RSP: 0018:ffffc90000a08d98 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffff8880b8728400 RCX: 0000000080010001 RDX: ffff888028a69f00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520001411ac R12: 0000000000000001 R13: dffffc0000000000 R14: ffff888076049300 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88812504c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000560038945950 CR3: 000000007a3e3000 CR4: 0000000000350ef0 Call Trace: enqueue_hrtimer+0x85/0x2c0 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:orc_find arch/x86/kernel/unwind_orc.c:222 [inline] RIP: 0010:unwind_next_frame+0x1d6/0x2550 arch/x86/kernel/unwind_orc.c:510 Code: fd f8 94 d5 8b 0f 93 c1 08 c1 0f 85 0b 01 00 00 48 c7 c0 00 00 00 81 49 89 ef 49 29 c7 49 c1 ef 08 8b 15 7d 49 d8 0c 8d 42 ff <44> 39 f8 0f 86 6c 04 00 00 44 89 f8 4c 8d 2c 85 6c 07 9e 91 4c 89 RSP: 0018:ffffc90005f2efc0 EFLAGS: 00000212 RAX: 00000000000ad595 RBX: 0000000000000001 RCX: 0000000080000000 RDX: 00000000000ad596 RSI: ffffffff8c4bdd60 RDI: ffffffff8c4bdd20 RBP: ffffffff821e6421 R08: ffffffff8177927f R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb59c60 R12: dffffc0000000000 R13: ffffffff8177927f R14: ffffc90005f2f068 R15: 0000000000011e64 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 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+0xd84/0x14a0 mm/page_alloc.c:3011 folios_put_refs+0x9e9/0xb30 mm/swap.c:1057 free_pages_and_swap_cache+0x2ba/0x490 mm/swap_state.c:586 __tlb_batch_free_encoded_pages mm/mmu_gather.c:138 [inline] tlb_batch_pages_flush mm/mmu_gather.c:151 [inline] tlb_flush_mmu_free mm/mmu_gather.c:417 [inline] tlb_flush_mmu+0x6d3/0xa30 mm/mmu_gather.c:424 tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:549 exit_mmap+0x4b2/0x9f0 mm/mmap.c:1313 __mmput+0x118/0x420 kernel/fork.c:1187 exit_mm+0x221/0x2d0 kernel/exit.c:615 do_exit+0x6cd/0x2360 kernel/exit.c:997 do_group_exit+0x22d/0x2f0 kernel/exit.c:1152 get_signal+0x121b/0x12c0 kernel/signal.c:3046 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x730 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+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7faf0ed9e019 Code: Unable to access opcode bytes at 0x7faf0ed9dfef. RSP: 002b:00007faf0fbf20e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007faf0f026098 RCX: 00007faf0ed9e019 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007faf0f026098 RBP: 00007faf0f026090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007faf0f026128 R14: 00007ffd730cc2f0 R15: 00007ffd730cc3d8 task:modprobe state:R running task stack:23528 pid:23252 tgid:23252 ppid:15072 task_flags:0x400000 flags:0x00080000 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_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:60 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:409 [inline] RIP: 0010:deref_stack_reg+0xb5/0x220 arch/x86/kernel/unwind_orc.c:419 Code: 85 39 01 00 00 41 83 3f 00 0f 95 c0 4c 39 c5 0f 96 c1 20 c1 4d 39 c6 0f 97 c0 20 c8 3c 01 75 18 49 8d 40 08 48 39 e8 0f 97 c1 <4c> 39 f0 0f 96 c0 84 c1 0f 85 c0 00 00 00 49 8d 7f 28 48 89 f8 48 RSP: 0018:ffffc90006a4f1e0 EFLAGS: 00000206 RAX: ffffc90006a4f3b8 RBX: 1ffff92000d49e65 RCX: 0000000000000001 RDX: ffffc90006a4f368 RSI: dffffc0000000000 RDI: ffffc90006a4f338 RBP: ffffc90006a48000 R08: ffffc90006a4f3b0 R09: ffffc90006a4f378 R10: dffffc0000000000 R11: fffff52000d49e71 R12: 1ffff92000d49e66 R13: 1ffff92000d49e67 R14: ffffc90006a50000 R15: ffffc90006a4f328 unwind_next_frame+0x19bd/0x2550 arch/x86/kernel/unwind_orc.c:-1 __unwind_start+0x514/0x660 arch/x86/kernel/unwind_orc.c:787 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/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+0x1c5/0x640 mm/slub.c:6692 tomoyo_check_open_permission+0x32c/0x470 security/tomoyo/file.c:791 security_file_open+0xa9/0x240 security/security.c:2739 do_dentry_open+0x4a0/0x1380 fs/open.c:924 vfs_open+0x3b/0x340 fs/open.c:1052 do_open fs/namei.c:4700 [inline] path_openat+0x2e44/0x3830 fs/namei.c:4863 do_file_open+0x23e/0x4a0 fs/namei.c:4892 do_sys_openat2+0x115/0x200 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1385 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: 0033:0x7f1b4d4ba0ba RSP: 002b:00007fff2a2d3708 EFLAGS: 00000206 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fff2a2d3780 RCX: 00007f1b4d4ba0ba RDX: 0000000000080000 RSI: 00007fff2a2d3780 RDI: 00000000ffffff9c RBP: 00007fff2a2d3770 R08: 00007fff2a2d3977 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000016 R13: 00007f1b4d48e000 R14: 00007fff2a2d3990 R15: 0000000000000000 task:sed state:R running task stack:26920 pid:23254 tgid:23254 ppid:23253 task_flags:0x400000 flags:0x00080000 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_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:lock_release+0x2d7/0x3c0 kernel/locking/lockdep.c:5893 Code: 8d ca 11 00 00 00 00 eb b5 e8 55 ad 2e 0a f7 c3 00 02 00 00 74 b9 65 48 8b 05 45 48 ca 11 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 15 49 6d ff cc 48 8d 3d a2 37 b8 RSP: 0018:ffffc90007127318 EFLAGS: 00000286 RAX: 77bb8b0db411e300 RBX: 0000000000000206 RCX: 0000000000000046 RDX: 0000000000000001 RSI: ffffffff8e4b408e RDI: ffffffff8c4bdd80 RBP: ffff8880232d2ac8 R08: ffffffff81d76676 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb59c60 R12: 0000000000000001 R13: 0000000000000001 R14: ffffffff8eb59c60 R15: ffff8880232d1f00 rcu_lock_release include/linux/rcupdate.h:310 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] is_bpf_text_address+0x28d/0x2b0 kernel/bpf/core.c:750 kernel_text_address+0xa5/0xe0 kernel/extable.c:125 __kernel_text_address+0xd/0x30 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:385 arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 slab_free_hook mm/slub.c:2638 [inline] slab_free mm/slub.c:6377 [inline] kmem_cache_free+0x44f/0x650 mm/slub.c:6504 tear_down_vmas+0x312/0x520 mm/mmap.c:1262 exit_mmap+0x4ca/0x9f0 mm/mmap.c:1320 __mmput+0x118/0x420 kernel/fork.c:1187 exec_mm_put_old fs/exec.c:916 [inline] setup_new_exec+0x30d/0x360 fs/exec.c:1353 load_elf_binary+0xbcf/0x2950 fs/binfmt_elf.c:1024 search_binary_handler fs/exec.c:1694 [inline] exec_binprm fs/exec.c:1726 [inline] bprm_execve+0x9c7/0x1630 fs/exec.c:1778 do_execveat_common+0x4f4/0x670 fs/exec.c:1876 __do_sys_execve fs/exec.c:1949 [inline] __se_sys_execve fs/exec.c:1943 [inline] __x64_sys_execve+0x97/0xc0 fs/exec.c:1943 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: 0033:0x7f0b1fde2107 RSP: 002b:00007ffce0f721f8 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 0000560038956078 RCX: 00007f0b1fde2107 RDX: 00005600389560a0 RSI: 0000560038956078 RDI: 0000560038956130 RBP: 0000560038956130 R08: 00007ffce0f77e54 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 00005600389560a0 R13: 00007f0b1ffa7e8b R14: 00005600389560a0 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10502 jiffies! g135017 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:27496 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: CPU: 0 UID: 0 PID: 23239 Comm: syz.6.5323 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:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0x11e6/0x15f0 kernel/smp.c:912 Code: c0 75 7a 41 8b 1e 89 de 83 e6 01 31 ff e8 42 23 0c 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 ee 1e 0c 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 d3 1e 0c RSP: 0018:ffffc90003ddf960 EFLAGS: 00000246 RAX: ffffffff81baf5fd RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc9000dffa000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc90003ddfab0 R08: ffffffff90579d37 R09: 1ffffffff20af3a6 R10: dffffc0000000000 R11: ffffffff81750150 R12: 1ffff110170e81d1 R13: ffff8880b863c448 R14: ffff8880b8740e88 R15: 0000000000000001 FS: 00007f2ffd49c6c0(0000) GS:ffff888124f4c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007e44c000 CR4: 0000000000350ef0 Call Trace: clock_was_set+0x715/0x7e0 kernel/time/hrtimer.c:999 do_adjtimex+0x25d/0x370 kernel/time/timekeeping.c:3006 do_clock_adjtime kernel/time/posix-timers.c:1169 [inline] __do_sys_clock_adjtime kernel/time/posix-timers.c:1181 [inline] __se_sys_clock_adjtime kernel/time/posix-timers.c:1172 [inline] __x64_sys_clock_adjtime+0x252/0x340 kernel/time/posix-timers.c:1172 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: 0033:0x7f2ffc59e019 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2ffd49c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000131 RAX: ffffffffffffffda RBX: 00007f2ffc825fa0 RCX: 00007f2ffc59e019 RDX: 0000000000000000 RSI: 0000200000000280 RDI: 0000000000000000 RBP: 00007f2ffc63500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2ffc826038 R14: 00007f2ffc825fa0 R15: 00007ffde1cde3f8