@Peter I have a MSI GE62 6QD (skylake i67-700HQ) which is on the list of both
links you gave me.
Using acpi_osi=! acpi_osi="Windows 2009", I can launch lspci, but the system
freezes a minute or so later with 

[   92.249957] nouveau 0000:01:00.0: DRM: resuming kernel object tree...
[   92.337917] nouveau 0000:01:00.0: DRM: resuming client object trees...
[   98.017700] nouveau 0000:01:00.0: DRM: evicting buffers...
[   98.017704] nouveau 0000:01:00.0: DRM: waiting for kernel channels to go
idle...
[   98.017726] nouveau 0000:01:00.0: DRM: suspending client object trees...
[   98.020446] nouveau 0000:01:00.0: DRM: suspending kernel object tree...
[   98.617684] nouveau 0000:01:00.0: priv: HUB0: 10ecc0 ffffffff (1e40822c)

followed by a cpu lock.

Is there any debug info I can provide ?

@Pablo I have tried pcie_port_pm=off alone or together with the acpi_osi boot
flags, but it doesn't seem to make any difference.