From:   "Bao, Joseph" <joseph.bao@intel.com>
To:     Bjorn Helgaas <helgaas@kernel.org>
CC:     Bjorn Helgaas <bhelgaas@google.com>,
        "linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Stuart Hayes <stuart.w.hayes@gmail.com>,
        Lukas Wunner <lukas@wunner.de>
Subject: RE: HW power fault defect cause system hang on kernel 5.4.y
Thread-Topic: HW power fault defect cause system hang on kernel 5.4.y
Thread-Index: AdfPm0b60GGT2vlORua28HBxsdiYnQAnnSiAAUFzF9AAD8bKgABIu/sQ
Date:   Thu, 11 Nov 2021 02:16:57 +0000
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 <20211109152951.GA1146992@bhelgaas>
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Hi Bjorn,

Thanks for the encouragement! Stuart already helps patch the hang issue, do=
 I still go an open a report at https://bugzilla.kernel.org?=20

Regards
Joseph

-----Original Message-----
From: Bjorn Helgaas <helgaas@kernel.org>=20
Sent: Tuesday, November 9, 2021 11:30 PM
To: Bao, Joseph <joseph.bao@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>; linux-pci@vger.kernel.org; linux-k=
ernel@vger.kernel.org; Stuart Hayes <stuart.w.hayes@gmail.com>; Lukas Wunne=
r <lukas@wunner.de>
Subject: Re: HW power fault defect cause system hang on kernel 5.4.y

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=20
> has a defect keeping PCI_EXP_SLTSTA_PFD always HIGH.

A system hang in response to a hardware defect like this is never the expec=
ted 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 openin=
g a report at https://bugzilla.kernel.org with a description of how you tri=
gger the problem, and attaching the complete dmesg log and "sudo lspci -vv"=
 output.

Bjorn