Enable CONFIG_VGA_SWITCHEROO cause lspci on MSI GS60-070XCN stuck

[Drunkard Zhang]

Hi,

I may hit a bug, when enabled CONFIG_VGA_SWITCHEROO, run lspci command
on MSI GS60-070XCN will stuck, it eats 100% CPU of one core, and
CPU/memory allocation on this system fails sometimes.

I'll bisect later, put my enviroment here, hope you guys give me some hint :)

Tested kernel versions are: latest Linus' kernel code, 4.4.2-gentoo;

My hardware info:

23:25:37 ~ # lspci
00:00.0 Host bridge: Intel Corporation Sky Lake Host Bridge/DRAM
Registers (rev 07)
00:01.0 PCI bridge: Intel Corporation Sky Lake PCIe Controller (x16) (rev 07)
00:02.0 VGA compatible controller: Intel Corporation Device 191b (rev 06)
00:14.0 USB controller: Intel Corporation Sunrise Point-H USB 3.0 xHCI
Controller (rev 31)
00:14.2 Signal processing controller: Intel Corporation Sunrise
Point-H Thermal subsystem (rev 31)
00:16.0 Communication controller: Intel Corporation Sunrise Point-H
CSME HECI #1 (rev 31)
00:17.0 SATA controller: Intel Corporation Sunrise Point-H SATA
Controller [AHCI mode] (rev 31)
00:1c.0 PCI bridge: Intel Corporation Sunrise Point-H PCI Express Root
Port #1 (rev f1)
00:1c.2 PCI bridge: Intel Corporation Sunrise Point-H PCI Express Root
Port #3 (rev f1)
00:1c.3 PCI bridge: Intel Corporation Sunrise Point-H PCI Express Root
Port #4 (rev f1)
00:1c.4 PCI bridge: Intel Corporation Sunrise Point-H PCI Express Root
Port #5 (rev f1)
00:1d.0 PCI bridge: Intel Corporation Sunrise Point-H PCI Express Root
Port #9 (rev f1)
00:1f.0 ISA bridge: Intel Corporation Sunrise Point-H LPC Controller (rev 31)
00:1f.2 Memory controller: Intel Corporation Sunrise Point-H PMC (rev 31)
00:1f.3 Audio device: Intel Corporation Sunrise Point-H HD Audio (rev 31)
00:1f.4 SMBus: Intel Corporation Sunrise Point-H SMBus (rev 31)
01:00.0 3D controller: NVIDIA Corporation GM107M [GeForce GTX 960M] (rev a2)
02:00.0 Network controller: Qualcomm Atheros QCA6174 802.11ac Wireless
Network Adapter (rev 20)
03:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd.
RTS5249 PCI Express Card Reader (rev 01)
04:00.0 Ethernet controller: Qualcomm Atheros Device e0a1 (rev 10)
05:00.0 PCI bridge: Intel Corporation Device 1576
06:00.0 PCI bridge: Intel Corporation Device 1576
06:01.0 PCI bridge: Intel Corporation Device 1576
06:02.0 PCI bridge: Intel Corporation Device 1576
07:00.0 System peripheral: Intel Corporation Device 1575
09:00.0 USB controller: Intel Corporation Device 15b5
3e:00.0 Non-Volatile memory controller: Toshiba America Info Systems
Device 010f (rev 01)

Any other hints?

Attachment: config-4.5.0-rc5+
Description: Binary data