rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=333/1/0x4000000000000000 softirq=57686/57686 fqs=107 
	(detected by 1, t=10502 jiffies, g=73029, q=986)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 19205 Comm: syz.6.4094 Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:do_raw_spin_lock+0x8/0x280 kernel/locking/spinlock_debug.c:113
Code: ff ff e8 ab 04 60 00 e9 67 ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 7c 95 48 89 df e8 92 04 60 00 eb 8b 55 48 89 e5 41 57 41 56 <41> 55 41 54 53 48 83 e4 e0 48 81 ec 80 00 00 00 48 89 fb 65 48 8b
RSP: 0018:ffffc90000007c60 EFLAGS: 00000092
RAX: f5cf9bd4116ab200 RBX: ffff888057cb0ad8 RCX: f5cf9bd4116ab200
RDX: 0000000000000000 RSI: ffffffff8a0b2460 RDI: ffff888019f8a2e8
RBP: ffffc90000007c70 R08: dffffc0000000000 R09: fffffbfff1ff364f
R10: fffffbfff1ff364f R11: 1ffffffff1ff364e R12: ffff888019f8a2e8
R13: dffffc0000000000 R14: ffff888019f8a000 R15: 1ffff1100af9615b
FS:  00007fbc47e3e6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcbfbe6a000 CR3: 0000000079b19000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 spin_lock include/linux/spinlock.h:363 [inline]
 advance_sched+0x47/0x940 net/sched/sch_taprio.c:716
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1754
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:kasan_mem_to_shadow include/linux/kasan.h:55 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x3a/0x290 mm/kasan/generic.c:189
Code: 49 89 f8 49 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1 e8 2f 41 81 f8 ff ff 01 00 0f 82 43 02 00 00 49 bf 01 00 00 00 00 fc ff df <49> 89 fb 49 c1 eb 03 49 b8 00 00 00 00 00 fc ff df 4f 8d 0c 03 48
RSP: 0018:ffffc90003caf640 EFLAGS: 00000246
RAX: 1ffff92000795f01 RBX: ffffc90003caf800 RCX: ffffffff8880e8fb
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888062fb2a08
RBP: ffffc90003caf750 R08: 000000000001ffff R09: ffffed100ca4070d
R10: ffffed100ca4070d R11: 1ffff1100ca4070c R12: ffffc90003cafd78
R13: 0000000000000000 R14: dffffc0000000000 R15: dffffc0000000001
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 scm_recv+0xbb/0x540 include/net/scm.h:-1
 __unix_dgram_recvmsg+0x9bf/0xd50 net/unix/af_unix.c:2381
 ____sys_recvmsg+0x291/0x580 net/socket.c:-1
 ___sys_recvmsg+0x1af/0x4f0 net/socket.c:2697
 do_recvmmsg+0x344/0x7a0 net/socket.c:2791
 __sys_recvmmsg net/socket.c:2870 [inline]
 __do_sys_recvmmsg net/socket.c:2893 [inline]
 __se_sys_recvmmsg net/socket.c:2886 [inline]
 __x64_sys_recvmmsg+0x18d/0x240 net/socket.c:2886
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fbc49ff7929
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:00007fbc47e3e038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fbc4a21f080 RCX: 00007fbc49ff7929
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000004
RBP: 00007fbc4a079b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbc4a21f080 R15: 00007ffcee2a76f8
 </TASK>
rcu: rcu_preempt kthread starved for 10288 jiffies! g73029 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27808 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1e0 kernel/sched/core.c:6459
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 18429 Comm: kworker/1:9 Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events fqdir_free_fn
Call Trace:
 <IRQ>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_single+0x212/0x490 kernel/smp.c:758
Code: 48 44 89 f6 83 e6 01 31 ff e8 0a 6b 0b 00 41 83 e6 01 49 bc 00 00 00 00 00 fc ff df 75 0a e8 95 67 0b 00 e9 a3 00 00 00 f3 90 <f7> 44 24 48 01 00 00 00 0f 84 8e 00 00 00 e8 7b 67 0b 00 eb e9 e8
RSP: 0018:ffffc9000361fa40 EFLAGS: 00000293
RAX: ffffffff816c5b95 RBX: 0000000000000000 RCX: ffff888077c35940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000361fb30 R08: dffffc0000000000 R09: ffffed1017207679
R10: ffffed1017207679 R11: 1ffff11017207678 R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff920006c3f4c
 rcu_barrier+0x25d/0x4b0 kernel/rcu/tree.c:4078
 fqdir_free_fn+0x2f/0x130 net/ipv4/inet_fragment.c:166
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>