syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=e2e/1/0x4000000000000000 softirq=88899/88899 fqs=0 
	(detected by 0, t=10502 jiffies, g=172385, q=44)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5775 Comm: syz-executor.1 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:204 [inline]
RIP: 0010:atomic_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:707 [inline]
RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:78 [inline]
RIP: 0010:do_raw_spin_lock+0x132/0x2b0 kernel/locking/spinlock_debug.c:113
Code: 00 00 00 00 e8 af f5 57 00 be 04 00 00 00 48 8d 7c 24 28 e8 a0 f5 57 00 8b 44 24 28 ba 01 00 00 00 89 44 24 04 f0 0f b1 55 00 <0f> 85 91 00 00 00 65 44 8b 35 40 97 a6 7e 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc90000da8c48 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 1ffff920001b518a RCX: ffffffff815afc00
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000da8c70
RBP: ffffffff8cbbec68 R08: 0000000000000001 R09: 0000000000000003
R10: fffff520001b518e R11: 0000000000000000 R12: ffffffff8cbbec70
R13: ffffffff8cbbec78 R14: 1ffff920001b51a2 R15: ffff88808e0a1340
FS:  00007f0ade2fb700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200015f0 CR3: 000000006e376000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:117 [inline]
 _raw_spin_lock_irqsave+0x94/0xc0 kernel/locking/spinlock.c:159
 debug_object_deactivate lib/debugobjects.c:710 [inline]
 debug_object_deactivate+0x101/0x300 lib/debugobjects.c:698
 debug_hrtimer_deactivate kernel/time/hrtimer.c:421 [inline]
 debug_deactivate kernel/time/hrtimer.c:482 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1488 [inline]
 __hrtimer_run_queues+0x3cb/0xfc0 kernel/time/hrtimer.c:1584
 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x142/0x5e0 arch/x86/kernel/apic/apic.c:1097
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:711
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 sysvec_apic_timer_interrupt+0xe0/0x120 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:587
RIP: 0010:unwind_next_frame+0x37e/0x1f90 arch/x86/kernel/unwind_orc.c:459
Code: 00 00 00 00 00 fc ff df 4c 89 ca 48 c1 ea 03 0f b6 04 02 4c 89 ca 83 e2 07 38 d0 7f 08 84 c0 0f 85 6f 08 00 00 41 0f b6 40 04 <a8> 0f 0f 85 aa 00 00 00 49 8d 78 05 48 b8 00 00 00 00 00 fc ff df
RSP: 0018:ffffc900083d7620 EFLAGS: 00000246
RAX: 0000000000000015 RBX: 1ffff9200107aecc RCX: ffffffff81be2920
RDX: 0000000000000000 RSI: ffffffff8b237cd4 RDI: ffffffff8ac36358
RBP: 0000000000000001 R08: ffffffff8b237cec R09: ffffffff8b237cf0
R10: 000000000007201e R11: 000000000002bc8e R12: ffffc900083d7740
R13: ffffc900083d772d R14: ffffc900083d7748 R15: ffffc900083d76f8
 arch_stack_walk+0x81/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:123
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:494
 slab_post_alloc_hook mm/slab.h:586 [inline]
 slab_alloc mm/slab.c:3320 [inline]
 kmem_cache_alloc+0x12c/0x3b0 mm/slab.c:3484
 kmem_cache_zalloc include/linux/slab.h:659 [inline]
 __alloc_file+0x21/0x350 fs/file_table.c:101
 alloc_empty_file+0x6d/0x170 fs/file_table.c:151
 path_openat+0xe3/0x2750 fs/namei.c:3346
 do_filp_open+0x17e/0x3c0 fs/namei.c:3387
 do_sys_openat2+0x16f/0x3b0 fs/open.c:1179
 do_sys_open fs/open.c:1195 [inline]
 ksys_open include/linux/syscalls.h:1388 [inline]
 __do_sys_creat fs/open.c:1263 [inline]
 __se_sys_creat fs/open.c:1261 [inline]
 __x64_sys_creat+0xc9/0x120 fs/open.c:1261
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45c1d9
Code: Bad RIP value.
RSP: 002b:00007f0ade2fac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 0000000000002880 RCX: 000000000045c1d9
RDX: 0000000000000000 RSI: 0000000000000090 RDI: 0000000020000040
RBP: 000000000078bf38 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c
R13: 00007fff765c2f4f R14: 00007f0ade2fb9c0 R15: 000000000078bf0c
rcu: rcu_preempt kthread starved for 10502 jiffies! g172385 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I28912    10      2 0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3453 [inline]
 __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4178
 schedule+0xd0/0x2a0 kernel/sched/core.c:4253
 schedule_timeout+0x148/0x250 kernel/time/timer.c:1897
 rcu_gp_fqs_loop kernel/rcu/tree.c:1874 [inline]
 rcu_gp_kthread+0xae5/0x1b50 kernel/rcu/tree.c:2044
 kthread+0x3b5/0x4a0 kernel/kthread.c:291
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293