rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (3 ticks this GP) idle=7d3c/1/0x4000000000000000 softirq=70968/70968 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5861/1:b..l P5858/1:b..l rcu: (detected by 1, t=10502 jiffies, g=56229, q=95 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11463 Comm: syz.5.1754 Not tainted 6.16.0-rc2-syzkaller-00082-gfb4d33ab452e #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__sanitizer_cov_trace_pc+0x5d/0x70 kernel/kcov.c:235 Code: 18 16 00 00 83 fa 02 75 21 48 8b 91 20 16 00 00 48 8b 32 48 8d 7e 01 8b 89 1c 16 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 cc cc cc cc cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 RSP: 0018:ffffc90000007d00 EFLAGS: 00000006 RAX: ffffffff81aea188 RBX: ffff88802dcfc340 RCX: ffff8880321b5a00 RDX: 0000000000010000 RSI: 0000000000000001 RDI: 0000000000000020 RBP: 0000000000000010 R08: ffffffff8fa10df7 R09: 1ffffffff1f421be R10: dffffc0000000000 R11: fffffbfff1f421bf R12: dffffc0000000000 R13: 1ffff110170c4f78 R14: ffff8880b8627bc0 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125c51000(0063) knlGS:00000000f50eeb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000582f799c CR3: 000000005265e000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 0000000000000047 DR2: 0000000000000005 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: enqueue_hrtimer+0x148/0x3a0 kernel/time/hrtimer.c:1091 __run_hrtimer kernel/time/hrtimer.c:1778 [inline] __hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194 Code: 74 05 e8 ab 0c 5f f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 53 f8 27 f6 65 8b 05 3c 14 34 07 85 c0 74 40 48 c7 04 24 0e 36 RSP: 0018:ffffc90004b6ee80 EFLAGS: 00000206 RAX: e382ef2bcea58500 RBX: 0000000000000a02 RCX: e382ef2bcea58500 RDX: 0000000000000002 RSI: ffffffff8d9823c9 RDI: 0000000000000001 RBP: ffffc90004b6ef10 R08: ffffffff8fa10df7 R09: 1ffffffff1f421be R10: dffffc0000000000 R11: fffffbfff1f421bf R12: dffffc0000000000 R13: ffff88802dcfc0f0 R14: ffff88802dcfc2e8 R15: 1ffff9200096ddd0 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] taprio_change+0x3119/0x3f60 net/sched/sch_taprio.c:1972 taprio_init+0x959/0xbd0 net/sched/sch_taprio.c:2112 qdisc_create+0x7a9/0xea0 net/sched/sch_api.c:1333 __tc_modify_qdisc net/sched/sch_api.c:1758 [inline] tc_modify_qdisc+0x1426/0x2010 net/sched/sch_api.c:1822 rtnetlink_rcv_msg+0x779/0xb70 net/core/rtnetlink.c:6953 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:727 ____sys_sendmsg+0x505/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmsg+0x164/0x220 net/socket.c:2652 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf70fe539 Code: 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f50ee55c EFLAGS: 00000206 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000800007c0 RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 task:syz-executor state:R running task stack:20632 pid:5858 tgid:5858 ppid:5834 task_flags:0x400140 flags:0x20004002 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6965 preempt_schedule+0xae/0xc0 kernel/sched/core.c:6989 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] copy_pte_range mm/memory.c:1206 [inline] copy_pmd_range+0x6727/0x7000 mm/memory.c:1267 copy_pud_range mm/memory.c:1304 [inline] copy_p4d_range mm/memory.c:1328 [inline] copy_page_range+0xc46/0x1270 mm/memory.c:1416 dup_mmap+0xf57/0x1ac0 mm/mmap.c:1838 dup_mm kernel/fork.c:1477 [inline] copy_mm+0x13c/0x4b0 kernel/fork.c:1529 copy_process+0x1706/0x3c00 kernel/fork.c:2169 kernel_clone+0x21e/0x870 kernel/fork.c:2599 __do_compat_sys_ia32_clone arch/x86/kernel/sys_ia32.c:254 [inline] __se_compat_sys_ia32_clone arch/x86/kernel/sys_ia32.c:240 [inline] __ia32_compat_sys_ia32_clone+0x189/0x1e0 arch/x86/kernel/sys_ia32.c:240 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fd2539 RSP: 002b:00000000f75bfcbc EFLAGS: 00000206 ORIG_RAX: 0000000000000078 RAX: ffffffffffffffda RBX: 0000000001200011 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000056adb4a8 RBP: 00000000f7462ff4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 task:syz-executor state:R running task stack:21672 pid:5861 tgid:5861 ppid:5836 task_flags:0x400140 flags:0x20004000 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5896 Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 cb aa fe 10 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000426f470 EFLAGS: 00000206 RAX: 9f63e7ac5b4dbc00 RBX: 0000000000000202 RCX: 9f63e7ac5b4dbc00 RDX: 0000000000000001 RSI: ffffffff8db6f0d7 RDI: ffffffff8be28b80 RBP: ffff8880330c0b18 R08: ffffc9000426f5f8 R09: 0000000000000000 R10: ffffc9000426f658 R11: fffff5200084decd R12: 0000000000000001 R13: 0000000000000001 R14: ffffffff8e13eda0 R15: ffff8880330c0000 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 tomoyo_path_perm+0x3a2/0x4b0 security/tomoyo/file.c:842 security_inode_getattr+0x12f/0x330 security/security.c:2377 vfs_getattr fs/stat.c:259 [inline] vfs_statx_path fs/stat.c:299 [inline] vfs_statx+0x18e/0x550 fs/stat.c:356 do_statx fs/stat.c:769 [inline] __do_sys_statx fs/stat.c:823 [inline] __se_sys_statx+0x1a8/0x240 fs/stat.c:812 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf711e539 RSP: 002b:00000000f75dea20 EFLAGS: 00000206 ORIG_RAX: 000000000000017f RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 00000000f75ded80 RDX: 0000000000000900 RSI: 00000000000007ff RDI: 00000000f75deadc RBP: 00000000f75dec40 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g56229 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=34579 rcu: rcu_preempt kthread starved for 10502 jiffies! g56229 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:27128 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245