can't boot into system after enabling GvT

hello,

i've tried enabling support for GvT (gpu virtualization technology) in i915.conf on my manjaro system. But, for some reason, my pc doesn't start after that. It gets stuck in the user space. Disabling it again  makes everything work fine.  I'm running kernel 4.18.11, but this issue has been persisting since kernel 4.17.

the contents of `/etc/modprobe.d/i915.conf` are as follows :

```

options i915 enable_guc=3
#options i915 enable_fbc=1
#options i915 enable_gvt=1
options i915 fastboot=1
 

```

this is the output of `ls -al /lib/firmware/i915/`

```
total 1684
drwxr-xr-x  2 root root   4096 Sep  1 00:54 ./
drwxr-xr-x 91 root root  16384 Sep  1 00:54 ../
-rw-r--r--  1 root root   8380 Aug 26 05:47 bxt_dmc_ver1_07.bin
lrwxrwxrwx  1 root root     19 Aug 26 05:47 bxt_dmc_ver1.bin -> bxt_dmc_ver1_07.bin
-rw-r--r--  1 root root 140928 Aug 26 05:47 bxt_guc_ver8_7.bin
-rw-r--r--  1 root root 146432 Aug 26 05:47 bxt_guc_ver9_29.bin
-rw-r--r--  1 root root 154432 Aug 26 05:47 bxt_huc_ver01_07_1398.bin
-rw-r--r--  1 root root  11224 Aug 26 05:47 cnl_dmc_ver1_06.bin
-rw-r--r--  1 root root  11268 Aug 26 05:47 cnl_dmc_ver1_07.bin
-rw-r--r--  1 root root   8800 Aug 26 05:47 glk_dmc_ver1_04.bin
-rw-r--r--  1 root root   8616 Aug 26 05:47 kbl_dmc_ver1_01.bin
-rw-r--r--  1 root root   8840 Aug 26 05:47 kbl_dmc_ver1_04.bin
lrwxrwxrwx  1 root root     19 Aug 26 05:47 kbl_dmc_ver1.bin -> kbl_dmc_ver1_01.bin
-rw-r--r--  1 root root 142656 Aug 26 05:47 kbl_guc_ver9_14.bin
-rw-r--r--  1 root root 147776 Aug 26 05:47 kbl_guc_ver9_39.bin
-rw-r--r--  1 root root 218688 Aug 26 05:47 kbl_huc_ver02_00_1810.bin
-rw-r--r--  1 root root   8824 Aug 26 05:47 skl_dmc_ver1_23.bin
-rw-r--r--  1 root root   8928 Aug 26 05:47 skl_dmc_ver1_26.bin
-rw-r--r--  1 root root   8928 Aug 26 05:47 skl_dmc_ver1_27.bin
lrwxrwxrwx  1 root root     19 Aug 26 05:47 skl_dmc_ver1.bin -> skl_dmc_ver1_26.bin
-rw-r--r--  1 root root 109636 Aug 26 05:47 skl_guc_ver1.bin
-rw-r--r--  1 root root 128320 Aug 26 05:47 skl_guc_ver4.bin
-rw-r--r--  1 root root 129024 Aug 26 05:47 skl_guc_ver6_1.bin
lrwxrwxrwx  1 root root     18 Aug 26 05:47 skl_guc_ver6.bin -> skl_guc_ver6_1.bin
-rw-r--r--  1 root root 147520 Aug 26 05:47 skl_guc_ver9_33.bin
-rw-r--r--  1 root root 140992 Aug 26 05:47 skl_huc_ver01_07_1398.bin
```