Message-ID: <0000000000006af1a90573251240@google.com>
Date:   Sat, 11 Aug 2018 01:59:03 -0700
From:   syzbot <syzbot+1c69d94fe42901b029c1@...kaller.appspotmail.com>
To:     hpa@...or.com, kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
        mingo@...hat.com, pbonzini@...hat.com, rkrcmar@...hat.com,
        syzkaller-bugs@...glegroups.com, tglx@...utronix.de, x86@...nel.org
Subject: general protection fault in kvm_lapic_hv_timer_in_use

Hello,

syzbot found the following crash on:

HEAD commit:    8c8399e0a3fb Add linux-next specific files for 20180806
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1796b8e2400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1b6bc1781e49e93e
dashboard link: https://syzkaller.appspot.com/bug?extid=1c69d94fe42901b029c1
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+1c69d94fe42901b029c1@...kaller.appspotmail.com

RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004ce2d8 R14: 00000000004c4c6d R15: 0000000000000000
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
CPU: 1 PID: 27598 Comm: syz-executor2 Not tainted 4.18.0-rc8-next-20180806+  
#32
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:kvm_lapic_hv_timer_in_use+0x56/0xd0 arch/x86/kvm/lapic.c:1569
Code: c1 ea 03 80 3c 02 00 75 7a 48 8b 9b e0 03 00 00 e8 4f ec 64 00 48 8d  
7b 7c 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48  
89 fa 83 e2 07 38 d0 7f 04 84 c0 75 51 0f b6 5b 7c
RSP: 0018:ffff880196037398 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90006a2a000
RDX: 000000000000000f RSI: ffffffff81182bc1 RDI: 000000000000007c
RBP: ffff8801960373a0 R08: ffff8801ae9f0140 R09: ffffed0033772ba4
R10: ffffed0033772ba4 R11: ffff88019bb95d27 R12: 0000000000000001
R13: 1ffff10032c06e7a R14: ffff88019bb90260 R15: 0000000000000000
FS:  00007f9e4c576700(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000015447d0 CR3: 00000001b6019000 CR4: 00000000001426e0
Call Trace:
  kvm_arch_vcpu_load+0x4fa/0x940 arch/x86/kvm/x86.c:3103
  kvm_sched_in+0x82/0xa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3975
  __fire_sched_in_preempt_notifiers kernel/sched/core.c:2481 [inline]
  fire_sched_in_preempt_notifiers kernel/sched/core.c:2487 [inline]
  finish_task_switch+0x50d/0x870 kernel/sched/core.c:2679
  context_switch kernel/sched/core.c:2826 [inline]
  __schedule+0x884/0x1ec0 kernel/sched/core.c:3471
  preempt_schedule_common+0x22/0x60 kernel/sched/core.c:3595
  _cond_resched+0x1d/0x30 kernel/sched/core.c:4961
  slab_pre_alloc_hook mm/slab.h:421 [inline]
  slab_alloc mm/slab.c:3378 [inline]
  kmem_cache_alloc_trace+0x2c1/0x780 mm/slab.c:3618
  kmalloc include/linux/slab.h:513 [inline]
  kzalloc include/linux/slab.h:707 [inline]
  kvm_create_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:613  
[inline]
  kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:3214  
[inline]
  kvm_dev_ioctl+0xc37/0x1b10 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3241
  vfs_ioctl fs/ioctl.c:46 [inline]
  file_ioctl fs/ioctl.c:501 [inline]
  do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685
  ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702
  __do_sys_ioctl fs/ioctl.c:709 [inline]
  __se_sys_ioctl fs/ioctl.c:707 [inline]
  __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707
  do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x456cb9
Code: fd b4 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 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f9e4c575c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f9e4c5766d4 RCX: 0000000000456cb9
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000018
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004ce2d8 R14: 00000000004c4c6d R15: 0000000000000000
Modules linked in:
Dumping ftrace buffer:
    (ftrace buffer empty)
---[ end trace 33ef5bcbdea594e3 ]---
RIP: 0010:kvm_lapic_hv_timer_in_use+0x56/0xd0 arch/x86/kvm/lapic.c:1569
Code: c1 ea 03 80 3c 02 00 75 7a 48 8b 9b e0 03 00 00 e8 4f ec 64 00 48 8d  
7b 7c 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48  
89 fa 83 e2 07 38 d0 7f 04 84 c0 75 51 0f b6 5b 7c
RSP: 0018:ffff880196037398 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90006a2a000
RDX: 000000000000000f RSI: ffffffff81182bc1 RDI: 000000000000007c
RBP: ffff8801960373a0 R08: ffff8801ae9f0140 R09: ffffed0033772ba4
R10: ffffed0033772ba4 R11: ffff88019bb95d27 R12: 0000000000000001
R13: 1ffff10032c06e7a R14: ffff88019bb90260 R15: 0000000000000000
FS:  00007f9e4c576700(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000015447d0 CR3: 00000001b6019000 CR4: 00000000001426e0


---
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