Comment 100 for bug 1803179

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In , hhfeuer (hhfeuer-linux-kernel-bugs) wrote :

Since this issue seems to get bigger, more recent notebooks by ASUS, Dell/Alienware, Toshiba seem affected, I compared those acpi tables with the unaffected one from my notebook and noticed this in the _ON method of the PEGP scope:
            TREN = One
            LNKD = Zero
            While (LNKS < 0x07)
            {

If I counted the bits correctly, this is related to the root port to which the nvidia gpu is connected with
TREN=link retrain bit
LNKD=link disable bit
LNKS=link width
So it's setting the link to retrain, enables it and then waits for it to reach x8 width. On affected machines, I couldn't find it to set the retrain bit, is that what changed in Windows 10, always retraining so the acpi depends on that?
Maybe someone could check by patching the kernel to set the bit in the resume iter of the pci driver?