=============================
[ BUG: Invalid wait context ]
syzkaller #0 Not tainted
-----------------------------
syz.0.0/5324 is trying to lock:
ffff888053999bb0 (&gpc->lock){....}-{3:3}, at: kvm_xen_set_evtchn_fast+0x1f4/0x9a0 arch/x86/kvm/xen.c:1843
other info that might help us debug this:
context-{2:2}
locks held by syz.0.0/5324: 1, last CPU#0:
 #0: ffff88805399a110 (&kvm->srcu){.?.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:198 [inline]
 #0: ffff88805399a110 (&kvm->srcu){.?.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:305 [inline]
 #0: ffff88805399a110 (&kvm->srcu){.?.+}-{0:0}, at: kvm_xen_set_evtchn_fast+0x1bc/0x9a0 arch/x86/kvm/xen.c:1841
stack backtrace:
CPU: 0 UID: 0 PID: 5324 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_lock_invalid_wait_context kernel/locking/lockdep.c:4874 [inline]
 check_wait_context kernel/locking/lockdep.c:4946 [inline]
 __lock_acquire+0xf5b/0x2de0 kernel/locking/lockdep.c:5238
 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline]
 _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:271
 kvm_xen_set_evtchn_fast+0x1f4/0x9a0 arch/x86/kvm/xen.c:1843
 xen_timer_callback+0x109/0x220 arch/x86/kvm/xen.c:139
 __run_hrtimer kernel/time/hrtimer.c:2074 [inline]
 __hrtimer_run_queues+0x371/0xa10 kernel/time/hrtimer.c:2131
 hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2250
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0033:0x7f0bea072829
Code: 83 e6 07 0f 85 10 01 00 00 be 08 00 00 00 4c 89 ff 83 c5 01 e8 78 92 fe ff 49 8b 47 40 41 83 47 30 08 48 8d 48 f8 49 89 4f 40 <48> 89 58 f8 49 83 c5 01 45 3b 6c 24 04 0f 82 f4 fe ff ff 41 80 7f
RSP: 002b:00007fff61c87e00 EFLAGS: 00010202
RAX: 00007f0be9bcf000 RBX: ffffffff822a8f5e RCX: 00007f0be9bceff8
RDX: 00007f0be8dff230 RSI: 0000000000000008 RDI: 00007f0beaf55720
RBP: 0000000000000077 R08: 00007f0bea410000 R09: 00007f0bea412000
R10: 00000000822a8f62 R11: 0000000000000017 R12: 00007f0bea426128
R13: 0000000000000139 R14: ffffffff822a8f5e R15: 00007f0beaf55720
 </TASK>