=============================
[ BUG: Invalid wait context ]
syzkaller #0 Not tainted
-----------------------------
udevd/5271 is trying to lock:
ffff888051e19bb0 (&gpc->lock){....}-{3:3}, at: kvm_xen_set_evtchn_fast+0x1f4/0x9a0 arch/x86/kvm/xen.c:1822
other info that might help us debug this:
context-{2:2}
2 locks held by udevd/5271:
#0: ffff88801255f678 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_downgrade include/linux/mmap_lock.h:586 [inline]
#0: ffff88801255f678 (&mm->mmap_lock){++++}-{4:4}, at: vms_complete_munmap_vmas+0x224/0xbe0 mm/vma.c:1340
#1: ffff888051e1a110 (&kvm->srcu){.?.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline]
#1: ffff888051e1a110 (&kvm->srcu){.?.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline]
#1: ffff888051e1a110 (&kvm->srcu){.?.+}-{0:0}, at: kvm_xen_set_evtchn_fast+0x1bc/0x9a0 arch/x86/kvm/xen.c:1820
stack backtrace:
CPU: 0 UID: 0 PID: 5271 Comm: udevd 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:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_lock_invalid_wait_context kernel/locking/lockdep.c:4830 [inline]
check_wait_context kernel/locking/lockdep.c:4902 [inline]
__lock_acquire+0xe39/0x2cf0 kernel/locking/lockdep.c:5187
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline]
_raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240
kvm_xen_set_evtchn_fast+0x1f4/0x9a0 arch/x86/kvm/xen.c:1822
xen_timer_callback+0x109/0x220 arch/x86/kvm/xen.c:140
__run_hrtimer kernel/time/hrtimer.c:2032 [inline]
__hrtimer_run_queues+0x371/0xa10 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215
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+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:call_rcu+0x663/0x8b0 kernel/rcu/tree.c:3280
Code: 05 62 f0 09 0d 49 03 07 49 39 c6 7f 47 e8 b5 4b 23 00 9c 58 a9 00 02 00 00 75 1f f7 44 24 20 00 02 00 00 74 01 fb 48 83 c4 50 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 ce a5 29 0a cc e8 68 a3 26 0a f7
RSP: 0018:ffffc9000de3f8c8 EFLAGS: 00000282
RAX: 0000000000000002 RBX: ffff888043968400 RCX: 0000000000000046
RDX: 0000000000000007 RSI: ffffffff8e22b5ff RDI: ffffffff8c4bce80
RBP: ffff88801fc3c270 R08: ffffffff90576a37 R09: 1ffffffff20aed46
R10: dffffc0000000000 R11: fffffbfff20aed47 R12: 1ffff11003f87854
R13: 1ffff11003f8784e R14: 0000000000000008 R15: ffff88801fc3c2a0
slab_free_hook mm/slub.c:2641 [inline]
slab_free mm/slub.c:6377 [inline]
kmem_cache_free+0x462/0x650 mm/slub.c:6504
remove_vma mm/vma.c:473 [inline]
vms_complete_munmap_vmas+0x897/0xbe0 mm/vma.c:1361
do_vmi_align_munmap+0x3b7/0x4b0 mm/vma.c:1604
do_vmi_munmap+0x252/0x2d0 mm/vma.c:1652
__vm_munmap+0x241/0x3e0 mm/vma.c:3288
__do_sys_munmap mm/mmap.c:1079 [inline]
__se_sys_munmap mm/mmap.c:1076 [inline]
__x64_sys_munmap+0x60/0x70 mm/mmap.c:1076
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f61ad91e097
Code: 73 01 c3 48 8b 0d 61 2d 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 31 2d 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007ffefeaf7378 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000561f898035f0 RCX: 00007f61ad91e097
RDX: 0000561f89806178 RSI: 0000000000000200 RDI: 00007f61ae04a000
RBP: 0000000000000001 R08: 0000561f89a89ce0 R09: 0000561f8980aa00
R10: 0000000000000000 R11: 0000000000000246 R12: 0000561f898041e0
R13: 00007f61ae17339c R14: 0000000000000200 R15: 0000000000000009
----------------
Code disassembly (best guess):
0: 05 62 f0 09 0d add $0xd09f062,%eax
5: 49 03 07 add (%r15),%rax
8: 49 39 c6 cmp %rax,%r14
b: 7f 47 jg 0x54
d: e8 b5 4b 23 00 call 0x234bc7
12: 9c pushf
13: 58 pop %rax
14: a9 00 02 00 00 test $0x200,%eax
19: 75 1f jne 0x3a
1b: f7 44 24 20 00 02 00 testl $0x200,0x20(%rsp)
22: 00
23: 74 01 je 0x26
25: fb sti
26: 48 83 c4 50 add $0x50,%rsp
* 2a: 5b pop %rbx <-- trapping instruction
2b: 41 5c pop %r12
2d: 41 5d pop %r13
2f: 41 5e pop %r14
31: 41 5f pop %r15
33: 5d pop %rbp
34: e9 ce a5 29 0a jmp 0xa29a607
39: cc int3
3a: e8 68 a3 26 0a call 0xa26a3a7
3f: f7 .byte 0xf7