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Date: Tue, 5 Mar 2024 10:21:39 +0100
From: Lukas Wunner <lukas@wunner.de>
To: Ethan Zhao <haifeng.zhao@linux.intel.com>
Cc: bhelgaas@google.com, Smita.KoralahalliChannabasappa@amd.com,
	ilpo.jarvinen@linux.intel.com,
	sathyanarayanan.kuppuswamy@linux.intel.com,
	linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
	kbusch@kernel.org
Subject: Re: [PATCH pci-next] pci/edr: Ignore Surprise Down error on hot
 removal
Message-ID: <20240305092139.GA28325@wunner.de>
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 <f9fd8861-6bbb-469d-b0cb-2edc8598ecca@linux.intel.com>
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On Tue, Mar 05, 2024 at 10:09:20AM +0800, Ethan Zhao wrote:
> On 3/4/2024 7:58 PM, Lukas Wunner wrote:
> > On Mon, Mar 04, 2024 at 04:08:19AM -0500, Ethan Zhao wrote:
> > > -static void dpc_handle_surprise_removal(struct pci_dev *pdev)
> > > +bool  dpc_handle_surprise_removal(struct pci_dev *pdev)
> > >   {
> > > +	if (!dpc_is_surprise_removal(pdev))
> > > +		return false;
> > 
> > This change of moving dpc_is_surprise_removal() into
> > dpc_handle_surprise_removal() seems unrelated to the problem at hand.
> > 
> > Please drop it if it's unnecessary to fix the issue.
> 
> To only export one function dpc_is_surprise_removal()... or I have to
> export them both.
> Seems I should keep them intact or refactor them in separated patch ?

Please keep them intact and make both public.  (You're not "exporting"
the functions, there are no modular users.)

However, I doubt whether you need to respin this patch at all:


> Reproduced on "Hardware name: Intel Corporation ArcherCity/ArcherCity,
>  BIOS EGSDCRB1.86B.0107.D20.2310211929 10/21/2023"

Eagle Stream BIOS, isn't that an Intel-provided BIOS?

Sathya's comments sound like the BIOS is misbehaving.  If so,
then the first thing to do is ask the BIOS team to fix the issue.
We do not want to pollute the kernel with workarounds for BIOS bugs
that can be fixed in the field through a BIOS update.

Thanks,

Lukas