rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=1434/1/0x4000000000000000 softirq=18832/18836 fqs=0
rcu: 	(detected by 0, t=10505 jiffies, g=12797, q=591 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6723 Comm: syz.3.230 Not tainted 6.15.0-rc3-syzkaller-00109-gf73f05c6f711 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:debug_lockdep_rcu_enabled+0x2a/0x40 kernel/rcu/update.c:321
Code: f3 0f 1e fa 31 c0 83 3d 27 71 29 04 00 74 1e 83 3d ea 9e 29 04 00 74 15 65 48 8b 0c 25 08 10 75 92 31 c0 83 b9 ec 0a 00 00 00 <0f> 94 c0 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc
RSP: 0018:ffffc90000a08c68 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff8976a008 RCX: ffff88802bc53c00
RDX: 0000000000000001 RSI: ffffffff8d932f35 RDI: ffffffff8bc1c820
RBP: ffff88805a70c550 R08: 0000000000000000 R09: 0000000000080000
R10: 0000000000000000 R11: ffffffff8976a008 R12: ffff88802dbb2360
R13: ffff88802dbb2000 R14: 1839e41d3cc59500 R15: ffff88805a70c800
FS:  00007f22df95b6c0(0000) GS:ffff8881261cf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fa5ffff CR3: 00000000217cc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_read_lock include/linux/rcupdate.h:842 [inline]
 advance_sched+0xa1d/0xc90 net/sched/sch_taprio.c:985
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:preempt_schedule_irq+0xb0/0x150 kernel/sched/core.c:7090
Code: 24 20 f6 44 24 21 02 74 0c 90 0f 0b 48 f7 03 08 00 00 00 74 64 bf 01 00 00 00 e8 cb 53 3a f6 e8 36 d2 70 f6 fb bf 01 00 00 00 <e8> 4b ab ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24
RSP: 0018:ffffc9001cb06f80 EFLAGS: 00000282
RAX: 7a447d697ea68700 RBX: 0000000000000000 RCX: 7a447d697ea68700
RDX: 0000000000000006 RSI: ffffffff8d747e11 RDI: 0000000000000001
RBP: ffffc9001cb07020 R08: ffffffff8f7ebe77 R09: 1ffffffff1efd7ce
R10: dffffc0000000000 R11: fffffbfff1efd7cf R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92003960df0
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:354
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:lockdep_unregister_key+0x2ba/0x310 kernel/locking/lockdep.c:6613
Code: 00 65 48 8b 05 f7 de d6 10 48 3b 44 24 10 0f 84 30 fe ff ff e8 27 15 b7 09 e8 52 16 b7 09 41 f7 c7 00 02 00 00 74 be fb 84 db <75> bd eb ce 90 0f 0b 90 31 db eb 89 90 0f 0b 90 e9 36 ff ff ff 48
RSP: 0018:ffffc9001cb070e8 EFLAGS: 00000246
RAX: 7a447d697ea68700 RBX: 0000000000000000 RCX: 7a447d697ea68700
RDX: ffffffff9338a708 RSI: ffffffff8d75b38e RDI: ffffffff8bc1c820
RBP: ffff888020b50a99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff81aaf758 R12: 0000000000000000
R13: 0000000000001000 R14: 0000000000000001 R15: 0000000000000a03
 __qdisc_destroy+0x166/0x3f0 net/sched/sch_generic.c:1080
 taprio_attach+0x25a/0x380 net/sched/sch_taprio.c:2147
 qdisc_graft+0x1172/0x1590 net/sched/sch_api.c:1175
 __tc_modify_qdisc net/sched/sch_api.c:1765 [inline]
 tc_modify_qdisc+0x1846/0x20b0 net/sched/sch_api.c:1821
 rtnetlink_rcv_msg+0x779/0xb70 net/core/rtnetlink.c:6964
 netlink_rcv_skb+0x219/0x490 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+0x219/0x270 net/socket.c:727
 ____sys_sendmsg+0x505/0x830 net/socket.c:2566
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620
 __sys_sendmsg net/socket.c:2652 [inline]
 __do_sys_sendmsg net/socket.c:2657 [inline]
 __se_sys_sendmsg net/socket.c:2655 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f22deb8e969
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:00007f22df95b038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f22dedb5fa0 RCX: 00007f22deb8e969
RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000004
RBP: 00007f22dec10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f22dedb5fa0 R15: 00007ffc28c5c378
 </TASK>
rcu: rcu_preempt kthread starved for 10505 jiffies! g12797 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:27304 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6860
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2248
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 6710 Comm: syz.0.226 Not tainted 6.15.0-rc3-syzkaller-00109-gf73f05c6f711 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xe69/0x11c0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 20 6d 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 cb 68 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 b0 68 0b
RSP: 0018:ffffc9001cc57380 EFLAGS: 00000293
RAX: ffffffff81b454d0 RBX: ffff8880b883ad40 RCX: ffff88802e983c00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9001cc574e0 R08: ffffffff8f7ebe77 R09: 1ffffffff1efd7ce
R10: dffffc0000000000 R11: ffffffff816f3eb0 R12: 1ffff11017127e99
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b893f4c8
FS:  0000000000000000(0000) GS:ffff8881260cf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc8dc87f08 CR3: 000000002ff6e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1275 [inline]
 flush_tlb_mm_range+0x6ae/0x12b0 arch/x86/mm/tlb.c:1365
 tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:480 [inline]
 zap_pte_range mm/memory.c:1758 [inline]
 zap_pmd_range mm/memory.c:1823 [inline]
 zap_pud_range mm/memory.c:1852 [inline]
 zap_p4d_range mm/memory.c:1873 [inline]
 unmap_page_range+0x35d6/0x4210 mm/memory.c:1894
 unmap_vmas+0x25d/0x3c0 mm/memory.c:1984
 exit_mmap+0x245/0xba0 mm/mmap.c:1284
 __mmput+0x118/0x420 kernel/fork.c:1379
 exit_mm+0x1da/0x2c0 kernel/exit.c:589
 do_exit+0x859/0x2550 kernel/exit.c:940
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
 __do_sys_exit_group kernel/exit.c:1113 [inline]
 __se_sys_exit_group kernel/exit.c:1111 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6de1f8e969
Code: Unable to access opcode bytes at 0x7f6de1f8e93f.
RSP: 002b:00007ffe86eb1ac8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6de1f8e969
RDX: 00007f6de0df9000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe86eb1b2c R08: 0000000386eb1bbf R09: 00000000000927c0
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000002c
R13: 00000000000927c0 R14: 000000000001baa3 R15: 00007ffe86eb1b80
 </TASK>