syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=542/1/0x4000000000000000 softirq=60451/60451 fqs=0 
	(detected by 0, t=10502 jiffies, g=106665, q=99)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 27967 Comm: syz-executor.2 Not tainted 5.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:trace_lock_release include/trace/events/lock.h:58 [inline]
RIP: 0010:lock_release+0x5f7/0x8e0 kernel/locking/lockdep.c:5022
Code: 0f b6 14 11 38 d0 7c 08 84 d2 0f 85 c4 02 00 00 8b 3d a5 95 57 09 85 ff 0f 85 1c fe ff ff e9 3e 71 00 00 65 ff 05 d9 89 a7 7e <48> 8b 05 3a b8 52 09 e8 fd ba 96 06 85 c0 74 0d 80 3d 88 55 52 09
RSP: 0018:ffffc90000da8c20 EFLAGS: 00000003
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff815a707e
RDX: fffffbfff1563b02 RSI: 0000000000000008 RDI: ffffffff8ab1d808
RBP: 1ffff920001b5186 R08: 0000000000000000 R09: ffffffff8ab1d80f
R10: fffffbfff1563b01 R11: 0000000000000001 R12: ffffffff8cc1c610
R13: ffffffff839dbf94 R14: 1ffff920001b51a2 R15: ffff88804f4f6b40
FS:  00007f5a8e2f0700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005593c50da238 CR3: 000000005bb6e000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline]
 _raw_spin_unlock_irqrestore+0x16/0xe0 kernel/locking/spinlock.c:191
 debug_object_deactivate lib/debugobjects.c:732 [inline]
 debug_object_deactivate+0x264/0x300 lib/debugobjects.c:698
 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
 debug_deactivate kernel/time/hrtimer.c:486 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1492 [inline]
 __hrtimer_run_queues+0x3cb/0xfc0 kernel/time/hrtimer.c:1588
 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1650
 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:706
 </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+0xb2/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:__kasan_check_read+0x4/0x10 mm/kasan/common.c:71
Code: f0 08 00 48 8b 73 58 89 c2 48 c7 c7 f8 88 6b 89 f7 da e8 fe 9f a9 ff e9 d1 f5 ff ff cc cc cc cc cc cc cc cc cc cc 48 8b 0c 24 <89> f6 31 d2 e9 b3 2a 00 00 0f 1f 00 48 8b 0c 24 89 f6 ba 01 00 00
RSP: 0018:ffffc90015d379c0 EFLAGS: 00000246
RAX: 0000000000040000 RBX: ffffea0001e63434 RCX: ffffffff81b48476
RDX: 0000000000040000 RSI: 0000000000000004 RDI: ffffea0001e63434
RBP: ffffea0001e63400 R08: 0000000000000000 R09: ffffea0001d6d947
R10: 0000000000000000 R11: 0000000000000000 R12: ffffea0001e63400
R13: 0000000000000000 R14: dffffc0000000000 R15: ffffea0001e63400
 instrument_atomic_read include/linux/instrumented.h:56 [inline]
 atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
 page_ref_count include/linux/page_ref.h:67 [inline]
 get_page include/linux/mm.h:1147 [inline]
 remove_migration_pte+0x2e6/0x10a0 mm/migrate.c:235
 rmap_walk_file+0x563/0xbf0 mm/rmap.c:1928
 rmap_walk+0x105/0x190 mm/rmap.c:1946
 remove_migration_ptes mm/migrate.c:304 [inline]
 __unmap_and_move mm/migrate.c:1133 [inline]
 unmap_and_move mm/migrate.c:1196 [inline]
 migrate_pages+0xc4c/0x2e50 mm/migrate.c:1444
 do_mbind+0xa17/0xcb0 mm/mempolicy.c:1371
 kernel_mbind mm/mempolicy.c:1492 [inline]
 __do_sys_mbind mm/mempolicy.c:1499 [inline]
 __se_sys_mbind mm/mempolicy.c:1495 [inline]
 __x64_sys_mbind+0x235/0x290 mm/mempolicy.c:1495
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45ce69
Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f5a8e2efc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed
RAX: ffffffffffffffda RBX: 000000000001fb80 RCX: 000000000045ce69
RDX: 0000000000000000 RSI: 0000000000c00007 RDI: 0000000020012000
RBP: 000000000118bf78 R08: 0000000000000000 R09: 0000010000000002
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007ffc910f736f R14: 00007f5a8e2f09c0 R15: 000000000118bf2c
rcu: rcu_preempt kthread starved for 10502 jiffies! g106665 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:
rcu_preempt     R  running task    29080    10      2 0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 schedule_timeout+0x148/0x250 kernel/time/timer.c:1879
 rcu_gp_fqs_loop kernel/rcu/tree.c:1888 [inline]
 rcu_gp_kthread+0xae5/0x1b50 kernel/rcu/tree.c:2058
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294