Re: HW power fault defect cause system hang on kernel 5.4.y

[Bjorn Helgaas]

On Tue, Nov 09, 2021 at 07:59:59AM +0000, Bao, Joseph wrote:
> Hi Lukas/Stuart,
> Want to follow up with you whether the system hang is expected when
> HW has a defect keeping PCI_EXP_SLTSTA_PFD always HIGH.

A system hang in response to a hardware defect like this is never the
expected situation.  Worst case we should be able to work around it
with a quirk.  Far better would be a generic fix that could recognize
and deal with the situation even without a quirk.

But I don't know the fix yet.  I'm just responding to encourage you to
keep pestering us and not give up :)  In the meantime, it might be
worth opening a report at https://bugzilla.kernel.org with a
description of how you trigger the problem, and attaching the complete
dmesg log and "sudo lspci -vv" output.

Bjorn