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From:   "Rafael J. Wysocki" <rafael@kernel.org>
Date:   Mon, 1 Jun 2020 12:58:49 +0200
Message-ID: <CAJZ5v0gxntUoxu70jpzsEHbytXwKC=EBsFD3y=0H6E0hLytybw@mail.gmail.com>
Subject: Re: Lost PCIe PME after a914ff2d78ce ("PCI/ASPM: Don't select
 CONFIG_PCIEASPM by default")
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Matthew Garrett <mjg59@srcf.ucam.org>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Bjorn Helgaas <helgaas@kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        "linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        ACPI Devel Maling List <linux-acpi@vger.kernel.org>
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On Sat, May 30, 2020 at 1:34 PM Christoph Hellwig <hch@infradead.org> wrote:
>
> On Sat, May 30, 2020 at 08:14:34AM +0100, Matthew Garrett wrote:
> > On Sat, May 30, 2020 at 08:33:50AM +0200, Heiner Kallweit wrote:
> >
> > > It *was* default y. This changed with a914ff2d78ce ("PCI/ASPM: Don't
> > > select CONFIG_PCIEASPM by default") and that's what triggered the
> > > problem. If there's no easy solution, then maybe it's best to revert
> > > the change for now.
> >
> > Oh, sorry, I was looking at mainline. CONFIG_PCIEASPM should
> > *definitely* be enabled by default - platforms expect the OS to support
> > it. If we want to get rid of default y then I think it'd make more sense
> > to have a CONFIG_DISABLE_PCIEASPM that's under EXPERT, and people who
> > really want to disable the code can do so.
>
> I think the fact that the EXPERT didn't get removed in the above bug
> is a defintive bug.  But I'd go further and think the CONFIG_PCIEASPM
> option should be removed entirely.  There is absolutely no good reason
> to not build this small amount of code if PCIe support is enabled.

Well stated, thanks!