general protection fault: 0000 [#1] PREEMPT SMP 
Modules linked in: drbg ctr ccm rfcomm bnep binfmt_misc arc4 iwldvm mac80211 iwlwifi snd_hda_codec_hdmi cfg80211 snd_hda_codec_idt snd_hda_codec_generic snd_hda_intel rtsx_usb snd_hda_codec snd_hwdep snd_hda_core uvcvideo snd_pcm btusb videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 btrtl videobuf2_core btbcm v4l2_common btintel bluetooth videodev dell_wmi sparse_keymap dell_laptop dcdbas snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_timer snd_seq_device snd x86_pkg_temp_thermal coretemp soundcore lpc_ich serio_raw parport_pc ppdev lp parport hid_generic nouveau i915 mxm_wmi ttm psmouse i2c_algo_bit drm_kms_helper syscopyarea sysfillrect usbhid ahci sysimgblt libahci fb_sys_fops hid drm wmi video
CPU: 1 PID: 975 Comm: Xorg Not tainted 4.4.0-rc6 #63
Hardware name: Dell Inc.          Inspiron 7720/04M3YM, BIOS A07 08/16/2012
task: ffff8800b2d3ca80 ti: ffff8800a7ebc000 task.ti: ffff8800a7ebc000
RIP: 0010:[<ffffffff813f95c5>]  [<ffffffff813f95c5>] swiotlb_unmap_sg_attrs+0x25/0x60
RSP: 0018:ffff8800a7ebfa28  EFLAGS: 00010293
RAX: fe171719fe171718 RBX: fe171719fe171718 RCX: 0000000000000000
RDX: fe171719fe171719 RSI: ff171819ff171719 RDI: ffff88013322f020
RBP: ffff8800a7ebfa50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 00000000000005bd R15: ffff880139850098
FS:  00007f002a221980(0000) GS:ffff88013f240000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000010f19e731004 CR3: 00000000328d0000 CR4: 00000000001406e0
Stack:
 ffff880135e40000 ffff880033b4a000 0000000000000001 ffff8800b2baef40
 ffff8800b2baef60 ffff8800a7ebfa80 ffffffffa01f624a ffff8800b2baef40
 ffff8800b2baef40 ffff8800b2baf030 ffff880135e40000 ffff8800a7ebfac0
Call Trace:
 [<ffffffffa01f624a>] i915_gem_gtt_finish_object+0x6a/0xc0 [i915]
 [<ffffffffa01fbd51>] i915_gem_object_put_pages_gtt+0x41/0x1b0 [i915]
 [<ffffffffa01fcda4>] ? i915_gem_vma_destroy+0xa4/0xe0 [i915]
 [<ffffffffa01f9625>] i915_gem_object_put_pages+0xa5/0x120 [i915]
 [<ffffffffa01fd9c6>] i915_gem_free_object+0x1e6/0x410 [i915]
 [<ffffffffa024b1ff>] ? intel_fb_obj_flush+0x4f/0xb0 [i915]
 [<ffffffffa001e280>] drm_gem_object_free+0x30/0x50 [drm]
 [<ffffffffa01f7dfc>] i915_gem_object_retire__read+0x1fc/0x280 [i915]
 [<ffffffffa01fa64b>] i915_gem_retire_requests_ring+0x7b/0x150 [i915]
 [<ffffffffa01ec2c1>] i915_gem_execbuffer_reserve.isra.17+0x31/0x350 [i915]
 [<ffffffffa01ed1e9>] i915_gem_do_execbuffer.isra.25+0x809/0x13e0 [i915]
 [<ffffffff8166521a>] ? sock_def_readable+0xba/0x2b0
 [<ffffffffa01eebd9>] i915_gem_execbuffer2+0xd9/0x280 [i915]
 [<ffffffffa001fadb>] drm_ioctl+0x14b/0x530 [drm]
 [<ffffffffa01eeb00>] ? i915_gem_execbuffer+0x340/0x340 [i915]
 [<ffffffff812569f5>] ? __fget+0x5/0x200
 [<ffffffff81256aee>] ? __fget+0xfe/0x200
 [<ffffffff8124afc1>] do_vfs_ioctl+0x301/0x550
 [<ffffffff81256c5a>] ? __fget_light+0x2a/0x90
 [<ffffffff8124b289>] SyS_ioctl+0x79/0x90
 [<ffffffff8174615b>] entry_SYSCALL_64_fastpath+0x16/0x73
Code: c3 0f 1f 44 00 00 55 83 f9 03 48 89 e5 41 57 41 56 41 55 41 89 cd 41 54 53 74 41 45 31 e4 85 d2 49 89 ff 48 89 f3 41 89 d6 7e 26 <8b> 53 18 44 89 e9 4c 89 ff 41 83 c4 01 48 8b 73 10 e8 85 ff ff 
RIP  [<ffffffff813f95c5>] swiotlb_unmap_sg_attrs+0x25/0x60
 RSP <ffff8800a7ebfa28>
---[ end trace 0bb6714e1dec71a3 ]---