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kernel BUG at drivers/vhost/vhost.c:1652!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 23006 Comm: syz-executor2 Not tainted 4.16.0-rc7+ #374
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:set_bit_to_user drivers/vhost/vhost.c:1652 [inline]
RIP: 0010:log_write+0x3ca/0x490 drivers/vhost/vhost.c:1676
RSP: 0018:ffff8801bf5e7940 EFLAGS: 00010212
RAX: 0000000000040000 RBX: dffffc0000000000 RCX: ffffffff854bcf2a
RDX: 000000000000005e RSI: ffffc900054c3000 RDI: ffff8801af52d918
RBP: ffff8801bf5e7a80 R08: 0000000020000200 R09: 0000000000000004
R10: ffff8801bf5e7b00 R11: 0000000000000004 R12: 0001ffffffffffff
R13: ffffed0037ebcf3b R14: ffff8801bf5e7a58 R15: ffff8801bf5e79d8
FS:  00007fca43f9a700(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b9bc25000 CR3: 00000001d05be003 CR4: 00000000001626f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 vhost_update_used_flags+0x379/0x480 drivers/vhost/vhost.c:1723
 vhost_vq_init_access+0xca/0x540 drivers/vhost/vhost.c:1763
 vhost_vsock_start drivers/vhost/vsock.c:446 [inline]
 vhost_vsock_dev_ioctl+0x6b2/0x890 drivers/vhost/vsock.c:678
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x455269
RSP: 002b:00007fca43f99c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fca43f9a6d4 RCX: 0000000000455269
RDX: 0000000020f82ffc RSI: 000000004004af61 RDI: 0000000000000014
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000351 R14: 00000000006f7038 R15: 0000000000000000
Code: 5e 41 5f 5d c3 31 c0 eb a6 e8 33 96 25 fc 4c 89 ef e8 ab 9a 44 fc 4c 89 f8 48 c1 e8 03 c6 04 18 f8 e9 3a ff ff ff e8 16 96 25 fc <0f> 0b e8 0f 96 25 fc 4d 8d 6c 24 ff e9 89 fe ff ff e8 00 96 25 
RIP: set_bit_to_user drivers/vhost/vhost.c:1652 [inline] RSP: ffff8801bf5e7940
RIP: log_write+0x3ca/0x490 drivers/vhost/vhost.c:1676 RSP: ffff8801bf5e7940
---[ end trace b7c18072a89779ff ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..