syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10504 jiffies, g=169961, q=72 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10500 (4295117375-4295106875), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10500 jiffies! g169961 f0x2 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:28064 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6960
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32270 Comm: syz.0.8039 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:instrument_atomic_read include/linux/instrumented.h:68 [inline]
RIP: 0010:atomic64_read include/linux/atomic/atomic-instrumented.h:1610 [inline]
RIP: 0010:taprio_set_budgets+0x130/0x310 net/sched/sch_taprio.c:676
Code: 10 48 8b 44 24 18 48 8d 78 20 48 89 f8 48 89 7c 24 20 48 c1 e8 03 48 89 44 24 28 e9 c1 00 00 00 e8 55 64 3f f8 48 8b 7c 24 20 <be> 08 00 00 00 e8 a6 39 a9 f8 48 8b 44 24 28 42 80 3c 38 00 0f 85
RSP: 0018:ffffc90000007d20 EFLAGS: 00000046
RAX: 0000000080010001 RBX: ffff888059766880 RCX: ffffffff897f8073
RDX: ffff888079a1a4c0 RSI: ffffffff897f7f6b RDI: ffff8880862412a0
RBP: 0000000000000000 R08: 0000000000000006 R09: 0000000000000000
R10: 000000000401004e R11: ffff888079a1aff0 R12: 0000000000000000
R13: ffff888059766800 R14: 000000000401004e R15: dffffc0000000000
FS:  00007fb5a89d76c0(0000) GS:ffff8881248fb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb5a89d5fb8 CR3: 00000000849db000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 advance_sched+0x5f6/0xc80 net/sched/sch_taprio.c:983
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x3c0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:80 [inline]
RIP: 0010:__orc_find+0x86/0xf0 arch/x86/kernel/unwind_orc.c:102
Code: f2 48 d1 fa 48 8d 5c 95 00 48 89 da 48 c1 ea 03 0f b6 34 0a 48 89 da 83 e2 07 83 c2 03 40 38 f2 7c 05 40 84 f6 75 4b 48 63 13 <48> 01 da 49 39 d5 73 af 4c 8d 63 fc 49 39 ec 73 b2 4d 29 f7 49 c1
RSP: 0018:ffffc9000e9177b0 EFLAGS: 00000246
RAX: ffffffff9122b2d6 RBX: ffffffff909eabf4 RCX: dffffc0000000000
RDX: fffffffff0e97054 RSI: 0000000000000000 RDI: ffffffff909eabe8
RBP: ffffffff909eabe8 R08: ffffffff9122b33c R09: 000000008b832b6c
R10: 0000000000000002 R11: 000000000000881c R12: ffffffff909eac04
R13: ffffffff81881ca8 R14: ffffffff909eabe8 R15: ffffffff909eabe8
 orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
 unwind_next_frame+0x2ec/0x20a0 arch/x86/kernel/unwind_orc.c:494
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:414
 kmalloc_noprof include/linux/slab.h:957 [inline]
 nfc_genl_rcv_nl_event net/nfc/netlink.c:1878 [inline]
 nfc_genl_rcv_nl_event+0xb9/0x310 net/nfc/netlink.c:1867
 notifier_call_chain+0xbc/0x3e0 kernel/notifier.c:85
 blocking_notifier_call_chain kernel/notifier.c:380 [inline]
 blocking_notifier_call_chain+0x69/0xa0 kernel/notifier.c:368
 netlink_release+0x1671/0x2000 net/netlink/af_netlink.c:761
 __sock_release+0xb3/0x270 net/socket.c:662
 sock_close+0x1c/0x30 net/socket.c:1455
 __fput+0x402/0xb70 fs/file_table.c:468
 fput_close_sync+0x118/0x260 fs/file_table.c:573
 __do_sys_close fs/open.c:1573 [inline]
 __se_sys_close fs/open.c:1558 [inline]
 __x64_sys_close+0x8b/0x120 fs/open.c:1558
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb5a7b8e3aa
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 43 91 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 a3 91 02 00 8b 44 24
RSP: 002b:00007fb5a89d5f90 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000025 RCX: 00007fb5a7b8e3aa
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000a
RBP: 000000000000000a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007fb5a7de6038 R14: 00007fb5a7de5fa0 R15: 00007ffd727b48f8
 </TASK>