From: "Rafael J. Wysocki" <rafael@kernel.org>
To: Jon Hunter <jonathanh@nvidia.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
Linux PCI <linux-pci@vger.kernel.org>,
Bjorn Helgaas <helgaas@kernel.org>,
Linux PM <linux-pm@vger.kernel.org>,
Linux ACPI <linux-acpi@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
Mika Westerberg <mika.westerberg@linux.intel.com>,
Keith Busch <kbusch@kernel.org>,
Kai-Heng Feng <kai.heng.feng@canonical.com>,
linux-tegra <linux-tegra@vger.kernel.org>
Subject: Re: [PATCH v2] PCI: PM: Skip devices in D0 for suspend-to-idle
Date: Mon, 24 Jun 2019 23:37:29 +0200 [thread overview]
Message-ID: <CAJZ5v0hdtXqoK84DpYtyMSCnkR9zOHFiUPAzWZDtkFmEjyWD1g@mail.gmail.com> (raw)
In-Reply-To: <9906d02b-8c77-f2c8-7168-93ea444b950e@nvidia.com>
On Mon, Jun 24, 2019 at 2:43 PM Jon Hunter <jonathanh@nvidia.com> wrote:
>
> Hi Rafael,
>
> On 13/06/2019 22:59, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> >
> > Commit d491f2b75237 ("PCI: PM: Avoid possible suspend-to-idle issue")
> > attempted to avoid a problem with devices whose drivers want them to
> > stay in D0 over suspend-to-idle and resume, but it did not go as far
> > as it should with that.
> >
> > Namely, first of all, the power state of a PCI bridge with a
> > downstream device in D0 must be D0 (based on the PCI PM spec r1.2,
> > sec 6, table 6-1, if the bridge is not in D0, there can be no PCI
> > transactions on its secondary bus), but that is not actively enforced
> > during system-wide PM transitions, so use the skip_bus_pm flag
> > introduced by commit d491f2b75237 for that.
> >
> > Second, the configuration of devices left in D0 (whatever the reason)
> > during suspend-to-idle need not be changed and attempting to put them
> > into D0 again by force is pointless, so explicitly avoid doing that.
> >
> > Fixes: d491f2b75237 ("PCI: PM: Avoid possible suspend-to-idle issue")
> > Reported-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> > Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
>
> I have noticed a regression in both the mainline and -next branches on
> one of our boards when testing suspend. The bisect is point to this
> commit and reverting on top of mainline does fix the problem. So far I
> have not looked at this in close detail but kernel log is showing ...
Can you please collect a log like that, but with dynamic debug in
pci-driver.c enabled?
Note that reverting this commit is rather out of the question, so we
need to get to the bottom of the failure.
next prev parent reply other threads:[~2019-06-24 21:37 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-13 21:59 [PATCH v2] PCI: PM: Skip devices in D0 for suspend-to-idle Rafael J. Wysocki
2019-06-24 12:43 ` Jon Hunter
2019-06-24 21:37 ` Rafael J. Wysocki [this message]
2019-06-24 22:20 ` Rafael J. Wysocki
2019-06-24 23:09 ` Rafael J. Wysocki
2019-06-25 12:46 ` Jon Hunter
2019-06-25 13:26 ` Jon Hunter
2019-06-25 16:23 ` Rafael J. Wysocki
2019-06-26 10:58 ` Mika Westerberg
2019-06-25 12:46 ` Jon Hunter
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAJZ5v0hdtXqoK84DpYtyMSCnkR9zOHFiUPAzWZDtkFmEjyWD1g@mail.gmail.com \
--to=rafael@kernel.org \
--cc=helgaas@kernel.org \
--cc=jonathanh@nvidia.com \
--cc=kai.heng.feng@canonical.com \
--cc=kbusch@kernel.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=linux-tegra@vger.kernel.org \
--cc=mika.westerberg@linux.intel.com \
--cc=rjw@rjwysocki.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).