Re: [PATCH v9 00/26] PCI: Allow BAR movement during boot and hotplug

From: Sergei Miroshnichenko <s.miroshnichenko@yadro.com>
To: "mika.westerberg@linux.intel.com" <mika.westerberg@linux.intel.com>
Cc: "David.Laight@aculab.com" <David.Laight@aculab.com>,
	"christian@kellner.me" <christian@kellner.me>,
	"christian.koenig@amd.com" <christian.koenig@amd.com>,
	"rajatja@google.com" <rajatja@google.com>,
	"YehezkelShB@gmail.com" <YehezkelShB@gmail.com>,
	"mario.limonciello@dell.com" <mario.limonciello@dell.com>,
	"helgaas@kernel.org" <helgaas@kernel.org>,
	"linux@yadro.com" <linux@yadro.com>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
	"sr@denx.de" <sr@denx.de>, "lukas@wunner.de" <lukas@wunner.de>,
	"andy.lavr@gmail.com" <andy.lavr@gmail.com>
Subject: Re: [PATCH v9 00/26] PCI: Allow BAR movement during boot and hotplug
Date: Wed, 10 Feb 2021 19:40:06 +0000	[thread overview]
Message-ID: <afc5d363476d445cfdf04b0ec4db9275db803af3.camel@yadro.com> (raw)
In-Reply-To: <20210204104912.GE2542@lahna.fi.intel.com>

On Thu, 2021-02-04 at 12:49 +0200, Mika Westerberg
wrote:
> On Wed, Feb 03, 2021 at 08:17:14PM +0000, Sergei Miroshnichenko
> wrote:
> > On Mon, 2021-02-01 at 14:55 +0200, Mika Westerberg wrote:
> > > On Thu, Jan 28, 2021 at 09:39:29PM +0100, Lukas Wunner wrote:
> > > > On Thu, Jan 28, 2021 at 08:53:16AM -0600, Bjorn Helgaas wrote:
> > > > > On Fri, Dec 18, 2020 at 08:39:45PM +0300, Sergei
> > > > > Miroshnichenko
> > > > > wrote:
> > > > > > ...
> > > > 
> > > > I intended to review and test this iteration of the series more
> > > > closely, but haven't been able to carve out the required time.
> > > > I'm adding some Thunderbolt folks to cc in the hope that they
> > > > can at least test the series on their development branch.
> > > > Getting this upstreamed should really be in the best interest
> > > > of Intel and other promulgators of Thunderbolt.
> > > 
> > > Sure. It seems that this series was submitted in December so
> > > probably
> > > not applicable to the pci.git/next anymore. Anyways, I can give
> > > it a
> > > try
> > > on a TBT capable system if someone tells me what exactly to test
> > > ;-)
> > > Probably at least that the existing functionality still works but
> > > something else maybe too?
> > 
> > For setups that worked fine, the only expected change is a possible
> > little different BAR layout (in /proc/iomem), and there should the
> > same
> > quantity (or more) of BARs assigned than before.
> > 
> > But if there are any problematic setups, which weren't able to
> > arrange
> > new BARs, this patchset may push a bit further.
> 
> Got it.
> 
> > In a few days I'll provide an updated branch for our mirror of the
> > kernel on Github, with a complete and bumped set of patches,
> > reducing
> > the steps required to test them.
> 
> Sounds good, thanks!

Hi Mika,

The branch is finally ready, so if you still have time for that, please
take a look:

https://github.com/YADRO-KNS/linux/tree/yadro/pcie_hotplug/movable_bars_v9.1

And a bit off topic: I've also updated the branch with a complete set
of our hotplug-related patches, including an RFC series of movable bus
numbers for hot-adding large and/or nested switches (at the cost of
breaking the sysfs+procsf ABI). In case one is ever going to try that,
the pci=realloc,movable_buses kernel command line arguments are needed:

https://github.com/YADRO-KNS/linux/commits/yadro/pcie_hotplug/movable_buses_v9.1

Thanks!

Serge