syzbot

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10130 ticks this GP) idle=c8bc/1/0x4000000000000000 softirq=65622/65622 fqs=138
rcu: 	(t=10500 jiffies g=120685 q=162 ncpus=2)
rcu: rcu_preempt kthread starved for 10216 jiffies! g120685 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:28280 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5376 [inline]
 __schedule+0xedb/0x5af0 kernel/sched/core.c:6688
 __schedule_loop kernel/sched/core.c:6763 [inline]
 schedule+0xe9/0x270 kernel/sched/core.c:6778
 schedule_timeout+0x137/0x290 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x1ec/0xb10 kernel/rcu/tree.c:1631
 rcu_gp_kthread+0x24b/0x380 kernel/rcu/tree.c:1830
 kthread+0x2c6/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x1b/0x20 drivers/acpi/processor_idle.c:112
CPU: 1 PID: 18948 Comm: syz-executor.4 Not tainted 6.7.0-rc2-syzkaller-00014-gc2d5304e6c64 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 e6 16 e5 f6 48 89 df e8 4e 8e e5 f6 f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f <bf> 01 00 00 00 e8 75 47 d7 f6 65 8b 05 46 c7 80 75 85 c0 74 12 5b
RSP: 0000:ffffc900001f0a90 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff8881417d4000 RCX: 1ffffffff23f11fc
RDX: 0000000000000000 RSI: ffffffff8accb960 RDI: ffffffff8b2f0e40
RBP: 0000000000000246 R08: 0000000000000001 R09: fffffbfff23e33f2
R10: ffffffff91f19f97 R11: 0000000000000004 R12: ffff88802b71aa00
R13: ffff88802b71a900 R14: dffffc0000000000 R15: 1ffff9200003e182
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020e68000 CR3: 000000000cd77000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 dummy_timer+0x1f57/0x3600 drivers/usb/gadget/udc/dummy_hcd.c:2001
 call_timer_fn+0x193/0x590 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x764/0xb20 kernel/time/timer.c:2022
 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035
 __do_softirq+0x21a/0x8de kernel/softirq.c:553
 invoke_softirq kernel/softirq.c:427 [inline]
 __irq_exit_rcu kernel/softirq.c:632 [inline]
 irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644
 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1076
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 e6 16 e5 f6 48 89 df e8 4e 8e e5 f6 f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f <bf> 01 00 00 00 e8 75 47 d7 f6 65 8b 05 46 c7 80 75 85 c0 74 12 5b
RSP: 0000:ffffc9000380f868 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffffffff929ecee0 RCX: 1ffffffff23ecf0e
RDX: 0000000000000000 RSI: ffffffff8accb960 RDI: ffffffff8b2f0e40
RBP: 0000000000000286 R08: 0000000000000001 R09: fffffbfff23e33e7
R10: ffffffff91f19f3f R11: 0000000000000002 R12: dffffc0000000000
R13: 0000000000011bb8 R14: 0000000000000000 R15: 0000000000000000
 __debug_check_no_obj_freed lib/debugobjects.c:1042 [inline]
 debug_check_no_obj_freed+0x245/0x4c0 lib/debugobjects.c:1063
 slab_free_hook mm/slub.c:1775 [inline]
 slab_free_freelist_hook+0x18c/0x1e0 mm/slub.c:1826
 slab_free mm/slub.c:3809 [inline]
 kmem_cache_free+0xf8/0x350 mm/slub.c:3831
 kfree_skbmem+0x166/0x1b0 net/core/skbuff.c:1036
 __tcp_close+0x247/0xfd0 net/ipv4/tcp.c:2777
 tcp_close+0x2d/0xc0 net/ipv4/tcp.c:2921
 inet_release+0x132/0x270 net/ipv4/af_inet.c:433
 __sock_release+0xae/0x260 net/socket.c:659
 sock_close+0x1c/0x20 net/socket.c:1419
 __fput+0x270/0xbb0 fs/file_table.c:394
 task_work_run+0x14d/0x240 kernel/task_work.c:180
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xa92/0x2ae0 kernel/exit.c:871
 do_group_exit+0xd4/0x2a0 kernel/exit.c:1021
 get_signal+0x23be/0x2790 kernel/signal.c:2904
 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309
 exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
 exit_to_user_mode_prepare+0x121/0x240 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x1e/0x60 kernel/entry/common.c:296
 do_syscall_64+0x4d/0x110 arch/x86/entry/common.c:88
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fac6827cae9
Code: Unable to access opcode bytes at 0x7fac6827cabf.
RSP: 002b:00007fac6905d0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: 000000000000d838 RBX: 00007fac6839c050 RCX: 00007fac6827cae9
RDX: 000000000000fe6a RSI: 00000000200012c0 RDI: 0000000000000004
RBP: 00007fac682c847a R08: 0000000000000000 R09: 0000000000000027
R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007fac6839c050 R15: 00007fac684bfa48
 </TASK>