linux-kernel - Re: [PATCH 06/16] PCI: of: Set fwnode.dev of newly created PCI device nodes

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250408145139.293c79a2@bootlin.com>
Date: Tue, 8 Apr 2025 14:51:39 +0200
From: Herve Codina <herve.codina@...tlin.com>
To: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>, "Rafael J. Wysocki"
 <rafael@...nel.org>, Danilo Krummrich <dakr@...nel.org>, Shawn Guo
 <shawnguo@...nel.org>, Sascha Hauer <s.hauer@...gutronix.de>, Pengutronix
 Kernel Team <kernel@...gutronix.de>, Fabio Estevam <festevam@...il.com>,
 Michael Turquette <mturquette@...libre.com>, Stephen Boyd
 <sboyd@...nel.org>, Andi Shyti <andi.shyti@...nel.org>, Wolfram Sang
 <wsa+renesas@...g-engineering.com>, Peter Rosin <peda@...ntia.se>, Derek
 Kiernan <derek.kiernan@....com>, Dragan Cvetic <dragan.cvetic@....com>,
 Arnd Bergmann <arnd@...db.de>, Rob Herring <robh@...nel.org>, Saravana
 Kannan <saravanak@...gle.com>, Bjorn Helgaas <bhelgaas@...gle.com>, Mark
 Brown <broonie@...nel.org>, Len Brown <lenb@...nel.org>, Daniel Scally
 <djrscally@...il.com>, Heikki Krogerus <heikki.krogerus@...ux.intel.com>,
 Sakari Ailus <sakari.ailus@...ux.intel.com>, Wolfram Sang <wsa@...nel.org>,
 Geert Uytterhoeven <geert+renesas@...der.be>, linux-kernel@...r.kernel.org,
 imx@...ts.linux.dev, linux-arm-kernel@...ts.infradead.org,
 linux-clk@...r.kernel.org, linux-i2c@...r.kernel.org,
 devicetree@...r.kernel.org, linux-pci@...r.kernel.org,
 linux-spi@...r.kernel.org, linux-acpi@...r.kernel.org, Allan Nielsen
 <allan.nielsen@...rochip.com>, Horatiu Vultur
 <horatiu.vultur@...rochip.com>, Steen Hegelund
 <steen.hegelund@...rochip.com>, Luca Ceresoli <luca.ceresoli@...tlin.com>,
 Thomas Petazzoni <thomas.petazzoni@...tlin.com>
Subject: Re: [PATCH 06/16] PCI: of: Set fwnode.dev of newly created PCI
 device nodes

Hi Andy,

On Mon, 7 Apr 2025 18:30:13 +0300
Andy Shevchenko <andriy.shevchenko@...ux.intel.com> wrote:

> On Mon, Apr 07, 2025 at 04:55:35PM +0200, Herve Codina wrote:
> > Device-tree node can be created when CONFIG_PCI_DYNAMIC_OF_NODES. Those
> > node are created and filled based on PCI core information but the
> > fwnode.dev field is not set.
> > 
> > When later an overlay is applied, this consuses fw_devlink. Indeed,
> > without any device attached to the node, fw_devlink considers that this
> > node will never become a device. When this node is pointed as a
> > supplier, devlink looks at its ancestors in order to find a node with a
> > device that could be used as the supplier.
> > 
> > In the PCI use case, this leads to links that wrongly use the PCI root
> > bridge device as the supplier instead of the expected PCI device.
> > 
> > Setting fwnode.dev to the dev of the PCI device allows devlink to use
> > this device as a supplier and so, correct links are created.  
> 
> ...
> 
> > +	/*
> > +	 * Set the fwnode.dev in order to have fw_devlink creating links
> > +	 * pointing to this PCI device instead of walking up to the PCI host
> > +	 * bridge.
> > +	 */
> > +	np->fwnode.dev = &pdev->dev;  
> 
> This is too invasive. I suppose here should be a helper for this kind of
> operation. If not, create one.
> 
> 	fw_devlink_set_device(...);
> 
> 
> or alike.

Yes, I will add
  void fw_devlink_set_device(struct fwnode_handle *fwnode, struct device *dev);

Also, I will probably add a new patch in this series in order to use
the new fw_devlink_set_device() when relevant in the already existing code.

Best regards,
Hervé